I E C 62 0 52 -3 1
®
Edition 1 .0 201 5-09
I N TE RN ATI ON AL
S TAN D ARD
colour
i n sid e
E l ectri ci ty m e teri n g eq u i pm e n t (AC ) – G en e ral re q u i re m en ts , tes ts an d tes t
con d i ti on s –
IEC 62052-31 :201 5-09(en)
P art 3 1 : P rod u ct safety req u i rem en ts an d te s ts
T H I S P U B L I C AT I O N I S C O P YRI G H T P RO T E C T E D
C o p yri g h t © 2 0 1 5 I E C , G e n e v a , S wi tz e rl a n d
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about I EC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local I EC member National Committee for further information.
IEC Central Office
3, rue de Varembé
CH-1 21 1 Geneva 20
Switzerland
Tel.: +41 22 91 9 02 1 1
Fax: +41 22 91 9 03 00
info@iec.ch
www.iec.ch
Ab ou t th e I E C
The I nternational Electrotechnical Commission (I EC) is the leading global organization that prepares and publishes
I nternational Standards for all electrical, electronic and related technologies.
Ab o u t I E C p u b l i ca ti o n s
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
I E C Catal og u e - webstore. i ec. ch /catal og u e
The stand-alone application for consulting the entire
bibliographical information on IEC International Standards,
Technical Specifications, Technical Reports and other
documents. Available for PC, Mac OS, Android Tablets and
iPad.
I E C pu bl i cati on s s earch - www. i ec. ch /search pu b
The advanced search enables to find IEC publications by a
variety of criteria (reference number, text, technical
committee,…). It also gives information on projects, replaced
and withdrawn publications.
E l ectroped i a - www. el ectroped i a. org
The world's leading online dictionary of electronic and
electrical terms containing more than 30 000 terms and
definitions in English and French, with equivalent terms in 1 5
additional languages. Also known as the International
Electrotechnical Vocabulary (IEV) online.
I E C G l os sary - s td . i ec. ch /g l oss ary
More than 60 000 electrotechnical terminology entries in
English and French extracted from the Terms and Definitions
clause of IEC publications issued since 2002. Some entries
have been collected from earlier publications of IEC TC 37,
77, 86 and CISPR.
I E C J u st Pu bl i s h ed - webstore. i ec. ch /j u stpu bl i sh ed
Stay up to date on all new IEC publications. Just Published
details all new publications released. Available online and
also once a month by email.
I E C C u stom er S ervi ce C en tre - webstore. i ec. ch /csc
If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: csc@iec.ch.
I E C 62 0 52 -3 1
®
Edition 1 .0 201 5-09
I N TE RN ATI ON AL
S TAN D ARD
colour
i n sid e
E l ectri ci ty m e teri n g e q u i pm en t (AC ) – G en eral req u i rem e n ts , tes ts an d tes t
con d i ti on s –
P art 3 1 : P rod u ct safety req u i rem en ts an d tes ts
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 1 9.080: 91 .1 40.50
ISBN 978-2-8322-2848-7
Warn i n g ! M ake su re th a t you obtai n ed th i s pu bl i cati on from an au th ori zed d i s tri bu tor.
® Registered trademark of the International Electrotechnical Commission
–2–
I EC 62052-31 :201 5 © I EC 201 5
CONTENTS
FOREWORD . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... . .. .. ... ... ... ... ... ... ... ... .. 8
I NTRODUCTI ON .. ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. . ... ... ... ... ... ... ... ... . 1 0
1
Scope and obj ect ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... . .. ... ... ... . 1 2
1 .1
Scope ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... ... ... 1 2
1 .2
Object ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... 1 3
1 . 2. 1
Aspects included in scope .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... ... ... ... . 1 3
1 . 2. 2
Aspects excluded from scope .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. 1 3
1 .3
Verification. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... . .. ... ... ... ... ... . 1 4
1 .4
Environm ental conditions .. ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. 1 4
1 . 4. 1
Normal environm ental conditions .. ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... 1 4
1 . 4. 2
Extended environm ental conditions . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . 1 4
1 . 4. 3
Extrem e environm ental conditions ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... .. ... . 1 5
2 Norm ative references . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. 1 5
3 Terms and definitions . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. 1 6
3. 1
Equipm ent and states of equipment .. ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... .. . ... ... ... ... ... ... 1 6
3. 2
Parts and accessories .. ... ... ... ... ... ... ... ... ... ... ... ... . .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . 1 7
3. 3
Quantities .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... . 1 9
3. 4
Tests . ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... . .. ... ... ... ... 21
3. 5
Safety term s . ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. . 21
3. 6
I nsulation . ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... .. ... ... ... ... . 25
3. 7
Terms related to switches of metering equipm ent ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... 29
4 Tests ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... .. 31
4. 1
General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... ... 31
4. 2
Type test – sequence of tests . ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. 31
4. 3
Reference test conditions... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... . 32
4. 3. 1
Atmospheric conditions .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 32
4. 3. 2
State of the equipment ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 32
4. 4
Testing in single fault condition .. .. ... ... ... ... ... ... ... ... ... ... ... ... . .. ... ... .. ... ... ... ... ... ... ... ... .. 36
4. 4. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 36
4. 4. 2
Application of fault conditions .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. 36
4. 4. 3
Duration of tests . ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... 38
4. 4. 4
Conformity after application of fault conditions ... ... ... ... ... ... ... ... ... ... ... ... .. .. . ... ... 38
5 I nform ation and marking requirements .. ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... ... ... ... ... .. ... 39
5. 1
General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... ... 39
5. 2
Labels, signs and signals ... ... ... ... ... .. ... ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. ... ... ... ... ... ... ... . 41
5. 2. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 41
5. 2. 2
Durability of markings . ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 43
5. 3
I nform ation for selection . ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... . 43
5. 3. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 43
5. 3. 2
General inform ation .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... 43
5. 3. 3
I nform ation related to meters / m etering elements .. ... ... ... ... ... ... ... ... .. ... ... ... ... . 44
5. 3. 4
I nform ation related to stand-alone tariff-and load control equipm ent ... ... ... ... .. 44
5. 3. 5
I nform ation related to suppl y control and load control switches .. .. ... ... ... ... ... ... 44
5. 4
I nform ation for installation and com missioning . ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... 44
5. 4. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 44
5. 4. 2
Handling and mounting .. ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... ... .. ... ... ... ... ... . 45
I EC 62052-31 :201 5 © I EC 201 5
–3–
5. 4. 3
Enclosure . ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . 45
5. 4. 4
Connection . ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... .. 45
5. 4. 5
Protection . ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... ... . 47
5. 4. 6
Auxiliary power suppl y ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 48
5. 4. 7
Supply for external devices . ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... .. 48
5. 4. 8
Batteries . ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... . 48
5. 4. 9
Self-consum ption ... ... ... ... ... ... ... ... ... ... .. .. . ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... 48
5. 4. 1 0
Commissioning ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... 49
5. 5
I nform ation for use .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... 49
5. 5. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 49
5. 5. 2
Display, push buttons and other controls . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. .. 49
5. 5. 3
Switches . ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... . .. .. ... ... . 49
5. 5. 4
Connection to user’s equipm ent .. ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... .. 50
5. 5. 5
External protection devices . ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... .. 50
5. 5. 6
Cleaning ... ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... ... . 50
5. 6
I nform ation for maintenance . ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. 50
6 Protection against electrical shock ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... . .. ... ... ... ... ... ... ... ... ... ... ... . 50
6. 1
General requirem ents .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... .. . ... ... ... ... ... ... ... ... ... ... ... ... ... 50
6. 2
Determination of accessible parts .. ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... .. . ... ... ... ... ... ... ... 51
6. 2. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 51
6. 2. 2
Exam ination ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . ... ... .. 51
6. 2. 3
Openings above parts that are hazardous live ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... 52
6. 2. 4
Openings for pre-set controls . ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. 52
6. 2. 5
Wiring terminals ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . . 53
6. 3
Lim it values for accessible parts .. ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... .. . ... ... ... ... ... .. ... ... 53
6. 3. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 53
6. 3. 2
Levels in normal condition .. ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... .. . ... .. ... ... ... ... ... ... .. 53
6. 3. 3
Levels in single fault condition . ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... ... ... ... ... .. 53
6. 4
Primary m eans of protection (protection against direct contact) . ... ... ... ... ... ... ... ... ... 56
6. 4. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 56
6. 4. 2
Equipm ent case ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... .. . ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. 56
6. 4. 3
Basic insulation ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... . .. ... .. ... ... ... ... ... ... ... ... ... ... ... .. 56
6. 4. 4
I m pedance ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... . .. ... ... . 56
6. 5
Additional m eans of protection in case of single fault conditions (protection
against indirect contact) .. ... ... ... ... ... ... ... ... ... ... ... ... ... . . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 57
6. 5. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 57
6. 5. 2
Protective bonding . ... ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... 57
6. 5. 3
Supplem entary insulation and reinforced insulation ... ... ... ... ... ... ... ... .. ... ... ... ... . 61
6. 5. 4
Protective im pedance . ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 61
6. 5. 5
Automatic disconnection of the suppl y .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... . 61
6. 5. 6
Current- or voltage-limiting device ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. . 62
6. 6
Connection to external circuits .. ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... ... ... ... ... .. ... ... 62
6. 6. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 62
6. 6. 2
Term inals for external circuits ... .. ... ... ... ... ... ... ... ... ... ... ... ... . .. ... ... .. ... ... ... ... ... ... .. 63
6. 6. 3
Term inals for stranded conductors ... ... ... ... ... ... ... ... ... ... ... ... ... . . ... ... ... ... ... ... ... ... 63
6. 7
I nsulation requirements ... ... ... ... ... ... ... ... ... ... ... ... .. . ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 63
6. 7. 1
General – Electrical stresses, overvoltages and overvoltage categories.. ... .. .. 63
6. 7. 2
The nature of insulation ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... . .. ... ... ... ... ... ... ... ... ... . 64
6. 7. 3
I nsulation requirem ents for m ains-circuits .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... .. 68
–4–
6. 7. 4
6. 7. 5
6. 7. 6
I EC 62052-31 :201 5 © I EC 201 5
I nsulation requirem ents for non-mains-circuits . ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... .. 74
I nsulation in circuits not addressed in 0 or 6. 7. 4 ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... 78
Reduction of transient overvoltages by the use of overvoltage limiting
devices ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... . 84
6. 8
I nsulation requirements between circuits and parts .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... . 84
6. 9
Constructional requirements for protection against electric shock . ... ... ... ... ... ... .. ... . 88
6. 9. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. . 88
6. 9. 2
I nsulating m aterials .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... 88
6. 9. 3
Colour coding ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. 88
6. 9. 4
Equipm ent case ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... .. . ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. 88
6. 9. 5
Term inal blocks .. ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... .. . ... ... ... ... ... ... ... ... ... .. ... ... ... ... 89
6. 9. 6
I nsulating m aterials of suppl y control and load switches . ... ... ... ... .. ... ... ... ... ... .. 89
6. 9. 7
Term inals . ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . 90
6. 9. 8
Requirem ents for current circuits .. ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... .. . ... ... ... ... ... 92
6. 1 0 Safety related electrical tests .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... ... ... ... ... ... ... ... .. 99
6. 1 0. 1
Overview .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . 99
6. 1 0. 2
Test m ethods . ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... .. . 1 01
6. 1 0. 3
Testing of voltage circuits ... ... ... .. ... ... ... ... ... ... ... ... ... ... . .. ... ... ... ... .. ... ... ... ... ... ... 1 04
6. 1 0. 4
Dielectric tests .. ... ... ... ... .. ... ... ... ... ... ... ... ... ... .. . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... 1 06
6. 1 0. 5
Electrical tests on current circuits of direct connected m eters without
suppl y control switches (SCSs) ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1 1 2
6. 1 0. 6
Electrical tests on current circuits of direct connected m eters with SCSs . ... . 1 1 3
6. 1 0. 7
Electrical tests on load control switches (LCSs) . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . 1 1 9
7 Protection against mechanical hazards . ... ... ... ... ... ... ... .. ... ... ... ... ... ... . .. ... ... ... ... ... ... ... ... .. . 1 22
7. 1
General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... . 1 22
7. 2
Sharp edges ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... .. . 1 22
7. 3
Provisions for lifting and carrying ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... . 1 23
8 Resistance to m echanical stresses .. ... ... .. ... ... ... ... ... ... ... ... ... ... .. . ... ... ... ... .. ... ... ... ... ... ... ... 1 23
8. 1
General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... . 1 23
8. 2
Spring hamm er test . ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 1 23
9 Protection against spread of fire ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... ... ... ... ... ... .. 1 24
9. 1
General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... . 1 24
9. 2
Elim inating or reducing the sources of ignition within the equipm ent .. ... ... ... ... ... .. 1 25
9. 3
Containm ent of fire within the equipment, should it occur . ... ... ... ... ... ... ... ... ... ... ... .. 1 25
9. 3. 1
General .. ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . . 1 25
9. 3. 2
Constructional requirem ents . ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1 26
9. 4
Lim ited-energy circuit . .. ... ... ... ... ... ... ... ... ... ... ... ... ... . .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 1 26
9. 5
Overcurrent protection . ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 1 28
1 0 Equipm ent temperature lim its and resistance to heat . ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... . .. ... 1 28
1 0. 1 Surface temperature lim its for protection against burns .. ... ... ... ... ... ... .. ... ... ... . ... ... . 1 28
1 0. 2 Temperature limits for terminals ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . 1 29
1 0. 3 Temperatures of internal parts .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. ... . 1 30
1 0. 4 Temperature test .. ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... 1 32
1 0. 5 Resistance to heat .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... ... ... ... ... ... ... .. ... ... ... ... ... . 1 33
1 0. 5. 1
Non-m etallic enclosures ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... .. 1 33
1 0. 5. 2
I nsulating m aterials .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... . 1 34
1 1 Protection against penetration of dust and water .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... 1 34
1 2 Protection against liberated gases and substances explosion and im plosi on –
Batteries and battery charging . ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... .. 1 36
I EC 62052-31 :201 5 © I EC 201 5
–5–
1 3 Components and sub-assemblies . ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... 1 36
1 3. 1 General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... . 1 36
1 3. 2 Mains transformers tested outside equipm ent ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. 1 38
1 3. 3 Printed wiring boards . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... . .. ... ... ... ... ... ... ... ... ... ... ... ... . 1 38
1 3. 4 Components bridging insulation ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... . .. ... ... ... ... ... .. ... . 1 38
1 3. 5 Circuits or com ponents used as transient overvoltage lim iting devices .. ... ... ... ... .. 1 38
1 4 Hazards resulting from application – Reasonabl y foreseeable misuse . ... ... ... ... ... ... ... ... 1 38
1 5 Risk assessment ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... . .. ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... .. . .. 1 39
Annex A (normative) Measuring circuits for touch current .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . 1 40
A. 1
Measuring circuit for a.c. with frequencies up to 1 MH z and for d.c. ... ... ... ... ... ... .. 1 40
A. 2
Measuring circuits for sinusoidal a.c. with frequencies up to 1 00 H z and for
d. c. .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... .. . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... . 1 41
A. 3
Current measuring circuit for electrical burns at high frequencies .. ... ... ... ... ... ... ... . 1 41
A. 4
Current measuring circuit for wet location . .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... 1 42
Annex B (informative) Exam ples for insulation between parts . ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. 1 43
B. 1
I nsulation between parts – Example 1 .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... . .. ... ... ... ... . 1 43
B. 2
I nsulation between parts – Example 2 .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... . 1 44
B. 3
I nsulation between parts – Example 3 .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... . 1 45
B. 4
I nsulation between parts – Example 4 .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... . 1 46
B. 5
I nsulation between parts – Example 5 .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... . 1 47
Annex C (inform ative) Exam ples for direct connected meters equipped with supply
control and load control switches ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... . .. ... ... ... ... ... .. ... ... ... ... ... ... 1 49
Annex D (norm ative) Test circuit diagram for the test of long term overvoltage
withstand ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... ... 1 51
Annex E (normative) Test circuit diagram for short current test on the current circuit of
direct connected m eters . ... ... ... ... ... ... ... ... ... ... ... ... ... ... . .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... . 1 52
Annex F (inform ative) Examples for voltage tests .. ... ... ... ... .. ... ... ... ... ... ... ... ... ... .. . ... ... ... ... .. ... 1 54
Annex G (norm ative) Additional a.c. voltage tests for electromechanical meters . ... ... ... ... ... 1 58
Annex H (norm ative) Test equipment for cable flexion and pull test .. ... ... ... ... ... ... ... ... ... ... ... 1 59
Annex I (inform ative) Routine tests .. ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... .. . ... ... ... ... .. ... ... ... ... ... ... 1 61
I.1
General . ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. . ... ... ... ... ... . 1 61
I.2
Protective earth . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... 1 61
I.3
AC power-frequency high-voltage test for mains-circuits . ... ... ... ... ... ... ... ... ... ... ... ... 1 61
I.4
Mains-circuits with voltage limiting devices .. ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... .. . ... .. 1 61
Annex J (inform ative) Examples of battery protection . ... ... ... ... ... ... ... ... ... .. ... ... ... . .. ... ... ... ... ... 1 62
Annex K (informative) Rationale for specifying overvoltage category I I I . ... ... ... ... ... ... ... ... ... . 1 63
K. 1
Transient overvoltage requirements in TC 1 3 standards ... ... ... ... ... ... ... ... ... ... ... ... .. 1 63
K. 2
Electricity m eters m entioned in basic safety publications and group safety
publications .. ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... .. . ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. 1 63
K. 2.1
I EC 60664-1 .. ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... .. . ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... 1 63
K. 2.2
I EC 60364-4-44 .. ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... .. . ... ... ... ... ... ... ... ... ... .. ... ... ... . 1 64
K. 2.3
I EC 61 01 0-1 .. ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... .. . ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... 1 64
K. 3
Conclusion .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... . .. .. ... ... ... .. 1 65
Annex L (informative) Overview of safety aspects covered . ... ... ... ... ... .. ... ... ... ... ... ... ... ... . .. ... . 1 66
Annex M (inform ative) I ndex of defined term s . ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. 1 81
Bibliograph y .. .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... ... ... ... ... ... ... . 1 84
–6–
I EC 62052-31 :201 5 © I EC 201 5
Figure 1 – Measurements through openings in enclosures ... ... ... ... ... ... ... .. ... ... ... ... ... .. . ... ... ... .. 52
Figure 2 – Maxim um duration of short-term accessible voltages in single fault
condition (see 6. 3. 3 a)) .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... .. . ... ... 54
Figure 3 – Capacitance level versus voltage in norm al condition and single fault
condition (see 6. 3. 2 c) and 6. 3.3 c)) .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . .. ... ... ... ... ... ... ... ... ... ... ... ... . 55
Figure 4 – Acceptable arrangements of protection means against electric shock ... ... ... ... ... ... . 57
Figure 5 – Exam ples of binding screw assem blies . ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... .. 59
Figure 6 – Distance between conductors on an interface between two layers .. ... ... ... ... ... ... ... . 72
Figure 7 – Distance between adjacent conductors along an interface of an inner layer ... ... ... 72
Figure 8 – Distance between adjacent conductors located between the sam e two
layers. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... . .. ... ... ... ... ... ... ... ... ... ... ... . 74
Figure 9 – Exam ple of recurring peak voltage ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... . .. ... ... ... ... ... .. . 82
Figure 1 0 – Flowchart of safety related electrical tests ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... . .. .. ... ... . 1 00
Figure 1 1 – Flow chart to explain the requirements for protection against the spread of
fire ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... .. 1 25
Figure 1 2 – Ball-pressure test apparatus... ... ... .. ... ... ... ... ... ... ... ... ... ... . .. ... ... ... ... .. ... ... ... ... ... ... . 1 34
Figure 1 3 – Flow chart for conformity options 1 3. 1 a), b), c) and d) . ... ... ... ... ... ... ... ... ... ... ... ... 1 37
Figure A. 1 – Measuring circuit for a.c. with frequencies up to 1 MH z and for d.c. . ... ... ... ... ... 1 40
Figure A. 2 – Measuring circuits for sinusoidal a.c. with frequencies up to 1 00 H z and
for d.c. .. ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... 1 41
Figure A. 3 – Current measuring circuit for electrical burns .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . 1 42
Figure A. 4 – Current measuring circuit for wet contact ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... .. ... ... . 1 42
Figure B. 1 – I nsulation between parts – Example 1 ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... 1 43
Figure B. 2 – I nsulation between parts – Example 2 ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... 1 44
Figure B. 3 – I nsulation between parts – Example 3 ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... 1 45
Figure B. 4 – I nsulation between parts – Example 4 ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... 1 46
Figure B. 5 – I nsulation between parts – Example 5 ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... 1 47
Figure C.1 – Single phase two wire meter with UC2 SCS and 25A LCS .. ... ... ... ... ... ... ... ... ... . 1 49
Figure C.2 – Three phase four wire m eter with UC2 SCS and 2A auxiliary control
switch ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... ... ... ... ... ... 1 50
Figure D.1 – Circuit for three-phase four-wire m eters to sim ulate long term
overvoltage, voltage moved to L3... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. . ... ... ... ... ... ... ... ... ... ... ... ... .. 1 51
Figure D.2 – Voltages at the m eter under test .. ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... 1 51
Figure E. 1 – Test circuit for verification of short-time withstand current test on current
circuits with and without suppl y control switches . ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. 1 52
Figure E. 2 – Example of short-circuit carrying test record in the case of a single-pole
equipm ent on single-phase a. c. ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... . .. ... ... ... ... ... ... ... .. ... ... ... ... .. 1 53
Figure F. 1 – Test arrangem ent for voltage tests: 3 phase 4 wire direct connected
meter with supply control and load control switches . ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... 1 54
Figure F. 2 – Test arrangem ent for voltage tests: 3 phase 4 wire transformer connected
meter . ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . .. ... ... ... ... .. ... ... ... ... ... ... 1 56
Figure H .1 – Test equipment for cable flexion and pull test (see 6.9. 7. 3) ... ... ... ... ... ... ... ... ... . 1 59
Figure J. 1 – N on-rechargeable battery protection .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... 1 62
Figure J. 2 – Rechargeable battery protection . ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... . 1 62
I EC 62052-31 :201 5 © I EC 201 5
–7–
Table 1 – Test copper conductors for current and switch terminals .. ... ... ... ... ... ... ... .. ... ... ... ... .. 35
Table 2 – I nform ation requirements ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. 40
Table 3 – I EC 6041 7 sym bols and I SO 7000 that m ay be used on metering equipment ... .. ... 42
Table 4 – Tightening torque for binding screw assem blies .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... .. . 60
Table 5 – Multiplication factors for clearance for altitudes up to 5 000 m . ... ... ... ... ... ... ... ... ... ... 64
Table 6 – Overview of clauses specifying requirem ents and tests for insulations . ... ... ... ... ... .. 67
Table 7 – N om inal / rated voltages and rated impulse voltages .. ... ... ... ... ... ... ... ... ... .. ... ... ... .. . .. 68
Table 8 – Clearances for m ains-circuits . ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. 69
Table 9 – Creepage distances for mains-circuits . ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... .. 70
Table 1 0 – Test voltages for solid insulation in mains-circuits .. ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... . 71
Table 1 1 – Test voltages for testing long-term stress of solid insulation in m ainscircuits .. ... ... ... ... .. ... ... ... ... ... ... ... ... .. . ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. 71
Table 1 2 – Minimum values for distance or thickness of solid insulation ... ... ... ... .. ... ... ... ... ... ... 73
Table 1 3 – Clearances and test voltages for non-m ains-circuits derived from mainscircuits of overvoltage category I I I . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... . 75
Table 1 4 – Creepage distances for non-m ains-circuits ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. . ... ... 75
Table 1 5 – Minimum values for distance or thickness (see 6. 7. 4.4.2 to 6. 7. 4. 4. 4) .. ... ... ... ... .. 77
Table 1 6 – Clearance values for the calculation of 6. 7. 5.2 .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... .. . 80
Table 1 7 – Test voltages based on clearances .. ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. . 81
Table 1 8 – Clearances for basic insulation in circuits having recurring peak voltages . ... ... ... 83
Table 1 9 – I solation classes for non-mains-circuits ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... . .. ... .. ... .. 85
Table 20 – I nsulation requirements between an y two circuits ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... . 86
Table 21 – Summ ary of requirements for current circuits of direct connected meters
without SCS .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... . .. ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. . ... ... ... ... ... ... ... .. 95
Table 22 – Summ ary of requirements for current circuits of direct connected meters
with SCS .. ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... ... ... ... ... ... .. 96
Table 23 – Summ ary of requirements for load control switches ... ... .. ... ... ... ... ... ... ... ... ... ... ... . .. . 98
Table 24 – Correction factors according to test site altitude for test voltages for
clearances . ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... . .. ... ... ... ... ... ... 1 04
Table 25 – AC voltage test ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. . ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... . 1 09
Table 26 – Test sequence and sam ple plan for suppl y control switches ... ... ... ... .. ... ... ... ... ... . 1 1 3
Table 27 – Power factor ranges of the test circuit .. ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... .. . ... ... .. ... 1 1 6
Table 28 – Test sequence and sam ple plan for load control switches . ... ... ... ... ... ... ... ... ... ... ... 1 20
Table 29 – Limits of m axim um available current .. ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... .. 1 27
Table 30 – Values for overcurrent protection devices .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... 1 27
Table 31 – Surface temperature lim its in normal condition .. ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... . 1 29
Table 32 – Tem perature limits for term inals ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... . .. ... ... ... ... ... ... . 1 30
Table 33 – Maxim um measured total tem peratures for internal materials and
com ponents .. ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... .. . ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1 31
Table G. 1 – AC voltage tests of electromechanical m eters . ... ... ... ... ... ... ... ... ... ... ... ... ... .. .. . ... .. 1 58
Table H . 1 – Test values for flexion and pull-out tests for round copper conductors . ... ... ... ... 1 60
Table L.1 – Overview of safety aspects ... ... ... ... ... .. ... ... ... ... ... ... ... ... .. . ... ... ... ... ... .. ... ... ... ... ... ... 1 66
–8–
I EC 62052-31 :201 5 © I EC 201 5
INTERNATI ONAL ELECTROTECHNI CAL COMMISSI ON
____________
E L E C T RI C I T Y M E T E RI N G E Q U I P M E N T ( AC ) –
G E N E R AL RE Q U I RE M E N T S , T E S T S AN D T E S T C O N D I T I O N S –
P a rt 3 1 :
P ro d u c t s a fe t y re q u i re m e n ts a n d te s ts
FOREWORD
1 ) The I nternati on al Electrotechni cal Comm ission (I EC) is a worl d wid e organization for stan dardization com prisin g
all n ation al el ectrotechnical comm ittees (I EC National Comm ittees). The object of I EC is to prom ote
internati onal co-operation on all q uestions concerni ng stand ardi zati on in the el ectrical an d electronic fi elds. To
this en d and in additi on to other acti vities, I EC pu blish es I nternational Stan dards, Techn ical Specificati ons,
Technical Reports, Publicl y Avail abl e Specificati ons (PAS) an d Gu ides (h ereafter referred to as “I EC
Publication(s)”). Th ei r preparation is entrusted to tech nical comm ittees; any I EC N ational Comm ittee interested
in the subj ect dealt with m ay partici pate in this preparatory work. I nternational, governm ental an d n on governm ental organ izations l iaising with th e I EC also participate i n this preparation. I EC collaborates closel y
with the I ntern ational Organi zation for Stand ardization (I SO) in accordance with con ditions determ ined by
agreem ent between th e two organi zati ons.
2) The form al decisions or ag reem ents of I EC on tech nical m atters express, as n early as possible, an i nternati onal
consensus of opi nion on the rel evant subjects since each technical com m ittee has representati on from all
interested I EC N ational Com m ittees.
3) I EC Publications have the form of recom m endations for intern ational use an d are accepted by I EC National
Com m ittees in that sense. While all reasonable efforts are m ade to ensure that th e technical content of I EC
Publications is accu rate, I EC cann ot be h eld responsi ble for th e way in which th ey are used or for an y
m isinterpretation by an y en d u ser.
4) I n order to prom ote intern ational u niform ity, I EC National Com m ittees und ertake to apply I EC Publications
transparentl y to the m axim um extent possible i n their national an d regi on al publicati ons. Any d ivergence
between an y I EC Publication and the correspondi ng national or regi on al publicati on sh all be clearl y in dicated in
the latter.
5) I EC itself d oes n ot provi de an y attestation of conform ity. I n depend ent certificati on bodies provi de conform ity
assessm ent services and, in som e areas, access to I EC m arks of conform ity. I EC is not responsi ble for any
services carri ed out by ind ependent certification bodi es.
6) All users shou ld ensure that th ey have the l atest editi on of thi s publicati on.
7) No liability shall attach to I EC or its directors, em ployees, servants or ag ents inclu din g in divi dual experts an d
m em bers of its technical com m ittees and I EC Nati on al Com m ittees for any person al i njury, property d am age or
other dam age of any nature whatsoever, wheth er di rect or indirect, or for costs (includ i ng leg al fees) and
expenses arisi ng out of the publ ication, use of, or relian ce upon, this I EC Publicati on or any other I EC
Publications.
8) Attention is drawn to th e N orm ative references cited in th is publ ication. Use of the referenced publ ications is
indispensable for the correct applicati on of this publication.
9) Attention is drawn to the possibility that som e of the elem ents of this I EC Publication m ay be the su bject of
patent rig hts. I EC shall not be held responsibl e for identifyi ng any or all such patent ri ghts.
I nternational Standard I EC 62052-31 has been prepared by I EC technical com mittee 1 3:
Electrical energ y measurement and control.
The text of this standard is based on the following docum ents:
FDI S
Report on votin g
1 3/1 639/FDI S
1 3/1 645/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the I SO/I EC Directives, Part 2.
I EC 62052-31 :201 5 © I EC 201 5
–9–
A list of all parts of I EC 62052 series, under the general title Electricity metering equipment
(AC) – General requirements, tests and test conditions , can be found on the I EC website.
In this standard, the following print types are used:
•
requirem ents and definitions: in roman type;
•
NOTES: in sm aller rom an type;
•
conformity and tests: in italic type.
The comm ittee has decided that the contents of this publication will rem ain unchanged until
the stability date indicated on the I EC web site under "http://webstore. iec. ch" in the data
related to the specific publication. At this date, the publication will be
•
•
•
•
reconfirm ed,
withdrawn,
replaced by a revised edition, or
amended.
A bilingual version of this publication may be issued at a later date.
I M P O R T AN T
th at
it
–
Th e
co n ta i n s
u n d e rs t a n d i n g
c o l o u r p ri n t e r.
of
' co l ou r
c o l o u rs
i ts
in si d e'
wh i ch
c o n te n ts .
l og o
a re
U s e rs
on
th e
cover
c o n s i d e re d
sh ou l d
p ag e
to
t h e re fo re
of th i s
be
p ri n t
p u b l i cati on
u s e fu l
th i s
fo r
i n d i c ate s
th e
d o cu m e n t
c o rre c t
u si ng
a
– 10 –
I EC 62052-31 :201 5 © I EC 201 5
INTRODUCTION
NOTE 1 The followin g text is based on I EC Gu ide 1 04, I SO/I EC Guid e 51 and I EC 60255-27: 201 3.
The I EC addresses safety aspects by establishing
publications.
b a sic
,
gro up
and
p roduct
safety
A b a sic sa fe ty p ub lica tion covers a specific safety-related matter, applicable to many
electrotechnical products. I t is prim aril y intended for use by technical committees in the
preparation of standards in accordance with the principles laid down in I EC Guide 1 04 and
I SO/I EC Guide 51 . I t is not intended for use by m anufacturers or certification bodies. One of
the responsibilities of a technical comm ittee is, wherever applicable, to make use of basic
safety publications in the preparation of its publications. The requirements, test m ethods or
test conditions of basic safety publications will not appl y unless specificall y referred to or
included in the relevant publications.
A gro up s a fe ty p ub lica tio n covers all safety aspects of a specific group of products within the
scope of two or more product TCs. Group safety publications are primaril y intended to be
stand-alone product safety publications, bu t m ay also be used by TCs as source m aterial in
the preparation of their publications.
A p ro duct s a fe ty p ub lica tio n covers all safety aspects of one or m ore products within the
scope of a single product TC.
Existing product standards established by TC 1 3 include a range of safety requirements, test
m ethods and test conditions. H owever, an im portant requirement of I EC Guide 1 04: 201 0,
5. 2. 3 has not been met so far:
“Sa fe ty a sp e cts a n d p e rform a n ce a sp e cts s h o uld n o t b e cove re d in th e s a m e p ub lica tio n ,
as
th is
m a ke s
it
difficult
to
a sse ss
co n form ity
with
s a fe ty
re q uire m e n ts
a lo n e .
If,
e xce p tio n a lly, th e re a re re a s o n s to cove r th e m in th e sa m e p ub lica tio n , s a fe ty a sp e cts a n d
p e rform a n ce
p e rform a n ce
a s p e cts
crite ria
s h a ll
wh ich
be
h a ve
cle a rly
distin guish e d
s a fe ty im p lica tion s ,
from
th e s e
e a ch
a re
o th e r.
If
co n s ide re d to
th e re
be
a re
sa fe ty
a sp e cts a n d th is s h a ll b e m a de cle a r in th e p ub lica tio n . ”
I n addition, some im portant aspects of product safety, such as safety under single fault
conditions, have not been covered so far.
The obj ectives of the developm ent of this I nternational Standard are the following:
•
•
•
•
•
to specificall y reference and include relevant requirements, test methods or test conditions
of relevant basic safety publications so that they becom e applicable;
to specificall y reference and include – where appropriate, in a m odified form – relevant
requirem ents, test m ethods or test conditions of relevant group safety publications;
to consider the latest developments in the technolog y used for the design and
m anufacture of equipm ent for electrical energy measurem ent and control;
to remove an y ambiguity resulting from the lack of a comprehensive product safety
standard for products in the Scope of TC 1 3;
to achieve a uniform approach to product safety throughout the international m etering
industry.
This
•
•
•
p ro duct s a fe ty sta n da rd
is based on, among others, the following:
the b a s ic s a fe ty sta n da rd I EC 60664-1 : 2007, established by TC 1 09;
standards from the I EC 60364 series related to electrical installations of buildings,
established by TC 64;
the gro up sa fe ty s ta n da rd I EC 61 01 0-1 : 201 0 established by TC 66;
I EC 62052-31 :201 5 © I EC 201 5
•
•
– 11 –
the group safety standard I EC 62477-1 : 201 2 established by TC 22;
IEC 60255-27:201 3, a product safety standard for m easuring relays and protection
equipm ent, established by TC 95. These products are similar in their design and to som e
extent in their use in equipment for electrical energ y m easurement and control,
To facilitate the use of this standard, an integral text has been prepared, with appropriate 539
references to source docum ents.
This standard cancels and replaces the safety requirements specified in earlier standards
established by I EC TC 1 3. See also Annex L (I nform ative).
NOTE 2 When this standard is publish ed, an am endm ent to the relevant stan dards affected by th is standard in
I EC 62052, I EC 62053 and I EC 62054 will be publ ished, to i ndicate which parts of those stand ards are replaced /
cancelled by this standard.
Being a product safety standard, this standard takes precedence over the group safety
standards I EC 61 01 0-1 :201 0 and I EC 62477-1 : 201 2.
– 12 –
I EC 62052-31 :201 5 © I EC 201 5
E L E C T RI C I T Y M E T E RI N G E Q U I P M E N T ( AC ) –
G E N E R AL RE Q U I RE M E N T S , T E S T S AN D T E S T C O N D I T I O N S –
P a rt 3 1 :
1
1 .1
P ro d u c t s a fe t y re q u i re m e n ts a n d te s ts
S cop e an d ob j ect
S co p e
This part of I EC 62052 specifies product safety requirem ents for equipment for electrical
energy measurement and control.
NOTE 1 For other req uirem ents, see the rel evant stan dards.
This I nternational Standard applies to newl y manufactured m etering equipment designed to
measure and control electrical energ y on 50 H z or 60 H z networks with a voltage up to 600 V,
where all functional elements, including add-on modules are enclosed in or form a single
case.
NOTE 2 The voltag e m ention ed above is the voltage l ine-to-neutral d erived from nom inal voltag es. See Table 7.
This I nternational Standard also applies to m etering equipment contain ing suppl y and load
control switches, but onl y those which are electromechanical in operation.
NOTE 3 For com ponents and sub-assem blies, see Clause 1 3.
When such equipm ent is designed to be installed in a specified m atching socket, then the
requirements appl y to, and the tests shall be perform ed on, equipment installed in its
specified m atching socket. However, requirem ents for sockets and inserting / rem oving the
meters from the socket are outside the scope of this standard.
This I nternational Standard is also applicable to auxiliary input and output circuits.
NOTE 4 Exam ples are im pulse inputs and outputs, control i n puts and outputs, circuits for m eter d ata exch ang e.
I n this standard distinction is m ade between:
•
•
•
•
•
electromechanical meters, static m eters and equipm ent for tariff and load control;
direct connected, current transformer operated, voltage and current transform er operated
meters;
protective class I and protective class I I equipm ent;
wall or cabinet mounted, rack m ounted and panel mounted equipm ent;
equipment intended for indoor use and outdoor use.
Equipm ent used in conjunction with equipment for electrical energ y m easurem ent and control
may need to compl y with additional safety requirements. See also Clause 1 3.
NOTE 5 Exam ples are tel ecomm unication m odem s and custom er inform ation units.
This I nternational Standard does not appl y to:
•
•
equipm ent where the voltage line-to-neutral derived from nom inal voltages exceeds 600 V;
portable meters;
NOTE 6 Portable m eters are m eters that are not perm anentl y conn ected.
I EC 62052-31 :201 5 © I EC 201 5
•
•
– 13 –
laboratory and mobile meter test equipm ent;
reference standard meters.
The safety requirements of this standard are based on the following assum ptions:
•
•
•
•
m etering equipment has been installed correctl y;
m etering equipment is used generall y by unskilled persons, including m eter readers and
consum ers of electrical energy. I n man y cases, it is installed in a way that it is freel y
accessible. I ts terminal covers cannot be rem oved and its case cannot be opened without
removing seals and using a tool;
during normal use all term inal covers, covers and barriers providing protection against
accessing hazardous live parts are in place;
for installation, configuration, m aintenance and repair it may be necessary to remove
term inal cover(s), (a part of) the case or barriers so that hazardous live parts m ay becom e
accessible. Such activities are perform ed by skilled personnel, who have been suitably
trained to be aware of working procedures necessary to ensure safety. Therefore, safety
requirem ents covering these conditions are out of the Scope of this standard.
1 .2
Obj ect
1 . 2. 1
Aspects i n cl u d ed i n scope
NOTE 1 Subclause 1 . 2 is based on I EC 61 01 0-1 : 201 0, 1 . 2.
The purpose of the requirements of this standard is to ensure that hazards to the user and the
surrounding area are reduced to a tolerable level.
Requirements for protection against particular types of hazard are given in Clauses 6 to 1 2 as
follows:
a)
b)
c)
d)
e)
f)
electrical shock or burn (see Clause 6);
m echanical hazards and stresses (see Clauses 7 and 8);
spread of fire from the equipment (see Clause 9);
excessive temperature (see Clause 1 0);
penetration of dust and water (see Clause 1 1 );
liberated gases, explosion and implosion (see Clause 1 2).
Requirements for components and sub-assem blies are specified in Clause 1 3.
Requirements for protection against hazards arising from reasonably foreseeable misuse are
specified in Clause 1 4.
Risk assessment for hazards or environments not fully covered above is specified in
Clause 1 5.
NOTE 2 Attenti on is drawn to th e existence of ad ditional requi rem ents specified by national authorities
responsibl e for health an d safety.
1 . 2. 2
Aspects excl u d ed from scope
This standard does not cover:
a) perform ance, reliability or other properties of the equipm ent not related to safety;
b) EMC requirements, which are covered by the relevant type testing standards;
NOTE 1 For EM C req uirem ents and test m ethods, see I EC 62052-1 1 : 2003, I EC 62052-21 : 2004 an d
I EC 62055-31 : 2005
c) protective m easures for explosive atm ospheres (see I EC 60079-0);
– 14 –
I EC 62052-31 :201 5 © I EC 201 5
d) functional safety requirem ents;
e) effectiveness of transport packaging;
f) safety requirements of installations.
NOTE 2 The l atter is g en erall y subj ect to national regulati on .
1 .3
Verification
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 1 . 3.
This standard also specifies methods of verifying that the equipment meets the requirements
of this standard, through inspection, type tests, risk assessm ent and routine tests. See
Clauses 4, 1 5 and Annex I respectively.
1 .4
Environmental conditions
1 .4.1
Normal environmental conditions
NOTE 1 Subclause 1 . 4 is based on I EC 61 01 0-1 : 201 0, 1 . 4.
This standard applies to metering equipment designed to be safe at least under the following
conditions:
a) indoor use;
b) altitude up to 2 000 m;
c) climatic conditions according to 3K5, but with low air temperature -1 0 o C; see
I EC 60721 -3-3: 1 994;
NOTE 2 3K5 specifies low air tem perature -5 °C, hi gh air tem perature +45 ° C, l ow relati ve hum idity 5 %, hig h
rel ative hum idity 95 %. See the clim atogram in I EC 60721 -3-3: 1 994, Figu re B. 5.
d) voltage fluctuations up to -20… 1 5 % of the nominal voltage;
The equipment m ay have several nominal voltages.
e) transient overvoltages up to the levels of overvoltage category I I I ;
f) transient overvoltages occurring on the mains suppl y (see 6. 7. 1 . 1 );
g) applicable pollution degree of the intended environment (pollution degree 2 in most
cases).
Manufacturers m ay specify more restricted environmental conditions for operation;
nevertheless, the equipm ent shall be safe within these norm al environmental conditions.
1 .4.2
Extended environmental conditions
This standard applies to m etering equipment designed to be safe not onl y under the
environmental conditions specified in 1 .4. 1 , but also under an y of the following conditions for
which the equipment is rated by the manufacturer:
a) outdoor use;
b) altitude above 2 000 m;
c) clim atic conditions according to 3K6; see I EC 60721 -3-3: 1 994;
NOTE 1 3K6 specifies low ai r tem perature -25 °C, hi gh air tem peratu re +55 °C, l ow rel ati ve h um idity 1 0 %,
high rel ative h um idity 1 00 %. See the clim atog ram in I EC 60721 -3-3: 1 994, Fi gure B. 6.
d) transient overvoltages higher than what is required for overvoltage category I I I .
NOTE 2 U nd er such circum stances, additi onal protection can be provid ed by extern al overvoltage protection
elem ents. However, this is beyond the Scope of this standard. I nform ation on th e effects of installin g varistors
in large quantities on the network can be fou nd in I EC TR 61 000-2-3: 1 992, 6. 6. 1 .
I EC 62052-31 :201 5 © I EC 201 5
1 .4.3
– 15 –
Extreme environmental conditions
NOTE 1 The followin g text is based on I EC 60721 -3-0: 1 984, 5. 2.
I t is recognized that extrem e environmental conditions m ay exist.
Elem ents determining the environm ental conditions m ay occur with an y of their severities in
com bination with other elements and their respective severities. An assum ption that each
element may occur with its highest severity would lead to unnecessary overdesign and cost.
Therefore, specifications for products to operate under such extreme environm ental
conditions are a m atter for negotiation between the m anufacturer and the purchaser.
NOTE 2 For specific clim atic conditions, see I EC 60721 -3-3: 1 994.
2
Normative references
The following docum ents, in whole or in part, are normativel y referenced in this docum ent and
are indispensable for its application. For dated references, onl y the edition cited applies. For
undated references, the latest edition of the referenced docum ent (including an y
amendments) applies.
I EC 60027-1 , Letter symbols to be used in electrical technology – Part 1: General
I EC 60068-2-75:201 4, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady
state
IEC 60085, Electrical insulation – Thermal evaluation and designation
IEC 601 1 2, Method for the determination of the proof and the comparative tracking indices of
solid insulating materials
IEC 60269-3, Low-voltage fuses – Part 3: Supplementary requirements for fuses for use by
unskilled persons (fuses mainly for household or similar applications) – Examples of
standardized systems of fuses A to F
IEC 60332-1 -2: 2004, Tests on electric and optical fibre cables under fire conditions –
Part 1-2: Test for vertical flame propagation for a single insulated wire or cable – Procedure
for 1 kW pre-mixed flame
IEC 60332-2-2: 2004, Tests on electric and optical fibre cables under fire conditions –
Part 2-2: Test for vertical flame propagation for a single small insulated wire or cable –
Procedure for diffusion flame
I EC 60364-4-44: 2007, Low-voltage electrical installations – Part 4-44: Protection for safety –
Protection against voltage disturbances and electromagnetic disturbances
I EC 6041 7-DB-1 2M, Graphical symbols for use on equipment
IEC 60529: 1 989,
Am d1 : 1 999
Am d2: 201 3
Degrees
of
protection
provided
I EC 6061 7-DB-1 2M, Graphical symbols for diagrams
by
enclosures
(IP
Code)
– 16 –
I EC 62052-31 :201 5 © I EC 201 5
I EC 60664-1 : 2007, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
I EC 60695-2-1 1 , Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods –
Glow-wire flammability test method for end-products (GWEPT)
IEC 60695-1 0-2, Fire hazard testing – Part 10-2: Abnormal heat – Ball pressure test method
IEC 60695-1 1 -1 0, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and vertical
flame test methods
IEC 60950-1 : 2005, Information technology equipment – Safety – Part 1: General requirements
Am d 1 : 2009
Am d 2: 201 3
IEC 61 032: 1 997, Protection of persons and equipment by enclosures – Probes for verification
I EC 61 1 80-2, High-voltage test techniques for low voltage equipment – Part 2: Test
equipment
I EC 62053-52, Electricity metering equipment (a.c.) – Particular requirements – Part 52:
Symbols
I SO 75-2, Plastics – Determination of temperature of deflection under load – Part 2: Plastics
and ebonite
I SO 306, Plastics – Thermoplastic materials – Determination of Vicat softening temperature
(VST)
ISO 3864-1 , Graphical symbols, Safety colours and safety signs – Part 1: Design principles
for safety signs and safety markings
ISO 7000: 2004, Graphical symbols for use on equipment – Registered symbols
3
Terms and definitions
For the purposes of this docum ent, the following term s and definitions apply.
3.1
Equ ipment and states of equipment
3.1 .1
equipment
device with functions related to electrical energy m easurem ent and control
Note 1 to entry: Exam ples include but are not lim ited to el ectricity m eters, paym ent m eters, tariff an d load control
equi pm ent. The term “m eter” is used in the text som etim es as a synonym of “m eterin g eq uipm ent”. A m eter m ay
includ e, in additi on to th e basic energ y m eterin g function, other functions.
3.1 .2
permanently connected equipment
equipm ent that is electricall y connected to a suppl y by means of a perm anent connection
which can be detached onl y by the use of a tool
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 1 . 2]
I EC 62052-31 :201 5 © I EC 201 5
– 17 –
3. 1 . 3
tool
external device, including keys and coins, used to aid a person to perform a m echanical
function
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 1 . 5]
3. 1 . 4
i sol ati on
function intended to prevent hazardous electric energ y from appearing, for reasons of safety,
in an electrical installation, or in a discrete section of the electrical installation, by separati ng
the electrical installation or section of it from every source of electric energy
[SOU RCE: I EC 60050-826: 2004, 826-1 7-01 , m odified – “to m ake dead” replaced by “to
prevent hazardous electric energ y from appearing “ and “all or a discrete section of the
electrical installation” replaced by “in an electrical installation, or in a discrete section of the
electrical installation”]
3. 2
Parts an d accessori es
3. 2. 1
protecti ve barri er
el ectri cal l y protecti ve barri er
part providing protection against direct contact from an y usual direction of access
Note 1 to entry: Depen din g on its construction, a protecti ve barri er can be call ed a casin g, cover, screen, door,
guard, etc.
A protective barrier can act al one; it is th en only effecti ve when it is i n place. A protective barri er can also act i n
conjuncti on with an interl ocking d evice with or with out guard locking; in this case, protection is ensu red whatever
the positi on of th e protective barrier.
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-06-1 5]
3. 2. 2
restri cted access area
area accessible onl y to electricall y skilled persons and electricall y instructed persons with the
proper authorization and knowledge of an y safety hazards
Note 1 to entry: These areas includ e closed switch plants, d istributi on plants, switchg ear cells, transform er cel ls,
distribution system s in m etal-sheet enclosu res or in oth er closed install ations.
[SOU RCE: I EC 60255-27:201 3, 3.56, I EC 60550: 1 998, 1 95-04-04, m odified – "and knowledge
of an y safety hazards" and a N ote have been added]
3. 2. 3
base
back of the meter by which it is generall y fixed and to which are attached the measuring
elem ent, the term inals or the term inal block, and the cover. For a flush-m ounted meter, the
meter base may include the sides of the case
[SOU RCE: I EC 62052-1 1 : 2003, 3. 3. 3]
3. 2. 4
cover
enclosure on the front of the meter, made either wholl y of transparent m aterial or opaque
material provided with window(s) through which the operation indicator (if fitted) and the
display can be read
[SOU RCE: I EC 62052-1 1 : 2003, 3. 3. 4]
– 18 –
I EC 62052-31 :201 5 © I EC 201 5
3. 2. 5
case
com prises the base and the cover. When the case is closed, it provides protection against
certain external influences and, in an y direction , protection against direct contact and spread
of fire
[SOU RCE: I EC 62052-1 1 : 2003, 3. 3. 5, m odified – second sentence added to align with the
term “enclosure” defined in I EC 61 01 0-1 : 201 0]
3. 2. 6
termi n al cover
cover which covers the meter terminals and, generally, the ends of the external wires or
cables connected to the terminals. When the meter is m ounted in its normal working position
and when the terminal cover is in place, it provides protection in an y direction against direct
contact (together with the case)
[SOU RCE: I EC 62052-1 1 :2003, 3. 3.9, m odified – second sentence added]
3. 2. 7
termi n al
conductive part of a device, electric circuit or electric network, provided for connecting that
device, electric circuit or electric network to one or m ore external conductors
[SOU RCE: I EC 60050-1 51 : 2001 , 1 51 -1 2-1 2, modified – Note which is not relevant in the
context of this standard om itted]
3. 2. 8
protecti ve con du ctor term i n al
term inal which is bonded to conductive parts of an equipment for safety purposes and is
intended to be connected to an external protective earthing system
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 2. 3]
3. 2. 9
referen ce earth
part of the Earth considered as conductive, the electric potential of which is conventionall y
taken as zero, being outside the zone of influence of an y earthing arrangem ent
Note 1 to entry: The concept "Earth" m eans the plan et and all its physical m atter.
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-01 -01 ]
3. 2. 1 0
earth
local earth
part of the Earth which is in electric contact with an earth electrode and the electric potential
of which is not necessarily equal to zero
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-01 -03]
3. 2. 1 1
in door m eter
meter intended for operation under norm al climatic conditions in a building or in a meter
cabinet
3. 2. 1 2
ou tdoor m eter
meter intended for operation under extended climatic conditions
I EC 62052-31 :201 5 © I EC 201 5
– 19 –
3. 2. 1 3
ven ti lated , ad j
designed with a means to perm it circulation of air sufficientl y to rem ove an excess of heat,
fumes, or vapours
[SOU RCE: I EC 60050-1 51 : 2001 , 1 51 -1 6-37]
3. 2. 1 4
meter cabi n et
enclosure for housing metering equipment and affording protection suitable for the intended
application
Note 1 to entry: I t m ay be fi xed on a wall, built in a wall recess or it m ay be free-standi n g an d self-su pportin g. I t
m ay also accomm odate el em ents of the electrical instal lation , like fuses, circuit breakers, residual cu rrent d evices.
3. 2. 1 5
specifi ed m atch i n g socket
base with jaws which accepts and connects to socket-mounted m etering equipment
Note 1 to entry: This i nclud es term inals for connection to the suppl y and l oad ci rcuits; al so appropriate secure
fi xin g an d seali ng arran gem ents.
Note 2 to entry: This term onl y relates to m eteri ng equi pm ent design ed as a socket-m ounted unit.
Note 3 to entry: Th e m eteri n g eq uipm ent is capable of m eeting the rel evant type testin g req uirem ents wh en it is
properl y instal l ed in an y specifi ed m atching socket.
[SOU RCE: I EC 62055-31 :2005, 3. 1 .9, modified – additional information is given in the N otes]
3. 2. 1 6
packag in g
products used for the containm ent, protection, handling, delivery and preservation of the
meter from the producer to the user or consum er
3. 3
Qu an titi es
3. 3. 1
rated valu e
value of a quantity used for specification purposes, established for a specified set of operating
conditions of a component, device, equipm ent, or system
[SOU RCE: I EC 60050-1 51 : 2001 , 1 51 -1 6-08]
3. 3. 2
ratin g
set of rated values and operating conditions
[SOU RCE: I EC 60050-1 51 : 2001 , 1 51 -1 6-1 1 ]
3. 3. 3
operatin g ran g e
range for which the equipm ent under specified conditions is able to perform its intended
function(s) according to the specified requirem ents
[SOU RCE: I EC 60050-447: 201 0, 447-03-1 6]
3. 3. 4
rated vol tag e
value of voltage assigned by the manufacturer, for a specified operating condition of a
com ponent, device or equipm ent
– 20 –
I EC 62052-31 :201 5 © I EC 201 5
Note 1 to entry: Eq uipm ent m ay h ave m ore than one rated voltag e valu e or m ay h ave a rated voltage range.
[SOU RCE: I EC 60255-27:201 3, 3. 54]
3.3.5
ambient air temperature
the temperature, determined under prescribed conditions, of the air surrounding the com plete
equipm ent
Note 1 to entry: For eq uipm ent install ed insid e a m eter cabinet, it is the tem perature of the air insid e th e m eter
cabinet.
Note 2 to entry: Th e am bient tem peratu re is m easured at h alf the distance from any n eig h bou rin g eq uipm ent, but
not m ore than 300 mm distance from the equipm ent case, at m iddle heig ht of the eq uipm ent, protected from direct
heat radi ation from the eq uipm ent.
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 1 -1 3, m odified – definition adapted to m etering and
Note 2 added]
3.3.6
rated maximum ambient temperature
a
t
maximum temperature at which the equipment m ay be operated continuousl y
[SOU RCE: I EC 61 558-1 : 2009, 3. 5. 8, modified – definition adapted to m etering and N ote
omitted]
3.3.7
working voltage
highest r.m .s. value of the a. c. or d.c. voltage across an y particular insulation which can occur
when the equipment is supplied at rated voltage
[SOU RCE: I EC 60050-581 : 2008, 581 -21 -1 9]
3.3.8
rated impulse voltage
im pulse withstand voltage value assigned by the manufacturer to the equipment or to a part of
it, characterizing the specified withstand capability of its insulation against transient
overvoltages
[SOU RCE: I EC 60664-1 : 2007, 3. 9. 2]
3.3.9
utilization category
UC
a com bination of specified requirem ents related to the condition in which a direct connected
meter with or without suppl y control switches fulfils its purpose, selected to represent a
characteristic group of practical applications
Note 1 to entry: The specifi ed requi rem ents m ay concern e. g. the valu es of short circuit cu rrent, m aking
capacities and breaking capacities (if applicable) and oth er characteristics, the associated circuits and the relevant
conditions of use and behavi ou r.
Note 2 to entry: Th e utili zation category provi des inform ation for the sel ection of the right m eter the
characteristics of which are properl y co-ordi nated with th e characteristics of th e su pply side short cu rrent
protection d evice that protects the m eter.
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-1 9, m odified – definition adapted to m etering and
Note 2 added]
I EC 62052-31 :201 5 © I EC 201 5
– 21 –
3. 3. 1 0
maxi m u m cu rren t
Im ax
highest value of current the m eter can carry continuousl y and remain safe, and at which it
purports to meet the accuracy requirem ents of the relevant standard
Note 1 to entry: Th e term “current” i ndicates r. m . s. values unl ess otherwise specifi ed.
[SOU RCE: I EC 62052-1 1 : 2003, 3. 5.2, m odified – to cover both the the safety and the
accuracy aspect]
3. 3. 1 1
maxi m u m overl oad cu rren t
Iovl
highest value of current, which is not caused by a short circuit, that a direct connected meter
can carry for a lim ited duration and rem ain safe
Note 1 to entry: Th e term “current” i ndicates r. m . s. values unl ess otherwise specifi ed.
Note 2 to entry: The val ue is at least equal to the m axim um current and it is subject to agreem ent between the
m anufacturer and th e purch aser takin g i nto accou nt the characteristics of the overcu rrent protection el em ents used
in the i nstallati on for wh ich the m etering equi pm ent is intend ed an d other instal lation con diti ons.
Note 3 to entry: This current i s not a rati ng and is not m andatoril y m arked on the equi pm ent.
3. 4
Tests
3. 4. 1
type test
test of one or more sam ples of equipment (or parts of equipm ent) made to a particular design
to show that the design and construction meet one or more requirem en ts of this standard
Note 1 to entry: This is an am plification of the I EC 60050-1 51 : 2001 , 1 51 -1 6-1 6 defi nition to cover desig n as well
as construction.
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 4. 1 ]
3. 4. 2
rou ti n e test
conform ity test made on each individual item during or after m anufacture
[SOU RCE: I EC 60050-1 51 : 2001 , 1 51 -1 6-1 7]
3. 5
Safety term s
3. 5. 1
accessi bl e part
part which can be touched by means of the standard test finger or test pin
[SOU RCE: I EC 60050-442: 1 998, 442-01 -1 5, m odified – to allow using either a test finger or a
test pin as appropriate]
3. 5. 2
hazard
potential source of harm
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 2]
3. 5. 3
h azard ou s l i ve
capable of rendering an electric shock or electric burn
– 22 –
I EC 62052-31 :201 5 © I EC 201 5
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 3]
3. 5. 4
cu rren t ci rcu it
internal connections of the meter and part of the m easuring elem ent through which flows the
current of the circuit to which the m eter is connected
[SOU RCE: I EC 62052-1 1 :2003, 3. 2. 6]
3. 5. 5
voltag e ci rcu it
internal connections of the m eter and part of the measuring elem ent supplied with the voltage
of the circuit to which the m eter is connected
Note 1 to entry: I n the case of static m eters, the electronic circuits are generall y supplied from the voltage
circuits. See also 3. 5. 9.
[SOU RCE: I EC 62052-1 1 : 2003, 3.2. 7, m odified – additional inform ation on supplying the
electronic circuits moved to the Note]
3. 5. 6
main s
electrical network suppl yi ng the prem ises
3. 5. 7
main s-ci rcu i t
electrical circuit which is conductively connected to and energized directl y from the m ains
Note 1 to entry: Voltage circuits inten ded to be conn ected to the second ary si de of m easurin g voltag e
transform ers are classed also as m ains-circuits.
3. 5. 8
n on -m ai n s-circu it
electrical circuit not energized directl y from the mains
Note 1 to entry:
Th is circuit m ay be isolated by a transform er or supplied by a battery.
Note 2 to entry: Whereas I EC 61 01 0-1 : 201 0 uses th e term s “prim ary circuit” and “second ary circu it”, in this
standard th e term s “m ains circuit” and “n on -m ains circuit’ are used, to avoid confusion with prim ary an d secondary
circuits of instrum ent transform ers used with transform er operated m eters.
[SOU RCE: I EC 62477-1 : 201 2, 3. 26, modified – additional inform ation is given in the Notes]
3. 5. 9
au xi l i ary su ppl y
a. c. or d. c. electrical power suppl y, other than the m easurand, provided via dedicated
terminals
Note 1 to entry: Provision of an au xiliary power supply m ay be necessary if the voltage ci rcuits m ay becom e deenergi zed for exten ded periods, and som e functions of the m eter shal l be neverthel ess m aintained. Such situati ons
often occur with m easuring voltage transform er operated m eters in substations.
[SOU RCE: I EC 60688: 201 2, 3. 1 .4, modified – definition adapted to metering and N ote added]
3. 5. 1 0
au xi l i ary d evice
device in the m eter intended to perform a particular function additional to the basic metrolog y
function
Note 1 to entry: Exam ples are: clock, tariff / load / suppl y control switch, im pulse in put / output, d ata exchange
unit.
I EC 62052-31 :201 5 © I EC 201 5
– 23 –
Note 2 to entry: An au xili ary device m ay be i nternal or external to a m eter.
3. 5. 1 1
au xi li ary ci rcu it
circuit other than the voltage m easurement, current m easurem ent and auxiliary suppl y circuits
intended to be connected to (an) external device(s)
[SOU RCE: I EC 62052-1 1 :2003, 3. 2. 8, modified – to reflect changes in technolog y]
3. 5. 1 2
protective i mped an ce
com ponent or assem bl y of com ponents whose impedance, construction and reliability are
suitable to provide protection against electric shock
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 6]
3. 5. 1 3
protective bon d i n g
electrical connection of accessible conductive parts or of protective screening to provide
electrical continuity to the m eans of connection of an external protective conductor
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 7]
3. 5. 1 4
n ormal u se
operation, including stand-by, according to the instructions for use or for the obvious intended
purpose
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 8]
3. 5. 1 5
n ormal con dition
condition in which all means of protection against hazards are intact
[SOU RCE: I EC Guide 1 04: 201 0, 3. 7, m odified – “against hazards” added]
3. 5. 1 6
sin gl e fau lt con d iti on
condition in which there is a fault of a single protection (but not a reinforced protection) or of a
single component or a device
Note 1 to entry: I f a sin gle fault cond ition results un avoid abl y in on e or m ore other fault conditions, all the fai lu res
are considered as on e singl e fault con dition.
[SOU RCE: I EC Guide 1 04: 201 0, 3. 8, modified – wording of N ote 1 am ended, “unavoidabl y”
added]
3. 5. 1 7
direct con tact
electric contact of persons or anim als with live parts
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-06-03]
3. 5. 1 8
in di rect con tact
electric contact of persons or anim als with exposed-conductive-parts which have becom e live
under fault conditions
– 24 –
I EC 62052-31 :201 5 © I EC 201 5
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-06-04]
3. 5. 1 9
u ser
person, other than a service person, installer or operator
[SOU RCE: I EC 60950-1 : 2005, 1 . 2. 1 3. 6, modified – to include installer and operator]
3. 5. 20
servi ce person
person having appropriate technical training and experience necessary to be aware of
hazards to which they m ay be exposed in perform ing a task and of measures to m inim ize the
risks for them selves or other persons
[SOU RCE: I EC 60950-1 : 2005, 1 . 2. 1 3. 5]
3. 5. 21
in stall er
service person responsible for the installation of metering equipment and, when applicable,
the provision of necessary safety related inform ation to the user
3. 5. 22
operator
service person responsible for operation and m aintenance of metering equipm ent and, when
applicable, the provision of necessary safety related information to the user
3. 5. 23
reason abl y foreseeabl e mi su se
use of a product in a way not intended by its provider but which may result from readil y
predictable hum an behaviour
Note 1 to entry: Fraudu lent attem pts are not consid ered as foreseeabl e m isuse.
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 1 4, modified – additional inform ation in the N ote added]
3. 5. 24
ri sk
com bination of the probability of the occurrence of harm and the severity of that harm
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 5. 1 5]
3. 5. 25
tolerable ri sk
level of risk that is accepted in a given context based on the current values of society
[SOU RCE: I SO/I EC Guide 51 : 201 4, 3. 1 5]
3. 5. 26
overvoltage categ ory
numeral defining a transient overvoltage condition
Note 1 to entry: IEC 60664-1 :2007 specifies overvoltag e categories I , I I , I I I and I V.
Note 2 to entry: The term ‘overvoltage category’ is synon ym ous with th e term ‘im pulse wi thstand voltage’ used i n
I EC 60364-4-44: 2007, 443.
[SOU RCE: I EC 60664-1 : 2007, 3. 1 0, modified – N ote 1 references IEC 60664-1 :2007]
I EC 62052-31 :201 5 © I EC 201 5
– 25 –
3. 5. 2 7
t ra n s i e n t o v e rv o l t a g e
short-duration overvoltage
Note 1 to entry: Transient overvoltages m ay be im m ediatel y foll owed by tem porary overvoltag es. I n such cases,
the two overvoltages are consi dered as separate events.
Note 2 to entry: I EC 60071 -1 defines three types of transient overvoltages, nam ely slow-front overvoltages, fastfront overvoltag es an d very fast-front overvoltages accordi ng to thei r tim e to peak, tail or total d uration, and
possible su perim posed oscil lati ons.
Note 3 to entry:
Th e d uration does not exceed a few m illiseconds.
Note 4 to entry:
dam ped.
The form of the transient overvoltag e m ay be oscillatory or non-oscillatory, but is usual ly highly
[SOU RCE: I EC 60050-604: 1 987, 604-03-1 3, modified – additional information m oved to
Notes]
3. 5. 2 8
t e m p o ra ry o v e rv o l t a g e
overvoltage of relativel y long duration
Note 1 to entry: The overvoltage is u nd am ped or weakly d am ped. Thou gh norm ally at the power freq uency, in
som e cases its frequency m ay be several tim es sm aller or hig her th an power-frequency.
[SOU RCE: I EC 60050-604: 1 987. 604-03-1 2, modified – to cover overvoltages with power
frequency or with other frequencies]
3. 6
I n s u l ati o n
3. 6. 1
e l e c t ri c i n s u l a t i o n
part of an electrotechnical product which separates conducting parts at different electrical
potentials during operation or insulates such parts from the surroundings
[SOU RCE: I EC 60050-21 2: 201 0, 21 2-1 1 -07]
3. 6. 2
fu n c t i o n a l
i n s u l ati o n
insulation between conductive parts, necessary for the proper functioning of the equipm ent
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-02-41 ]
3. 6. 3
basi c i n su l ati on
insulation of hazardous-live-parts which provides basic protection
Note 1 to entry: This concept does n ot apply to i nsul ation used exclusivel y for fu nction al pu rposes.
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-06-06]
3. 6. 4
s u p p l e m e n t a ry i n s u l a t i o n
independent insulation applied in addition to basic insulation in order to provide protection
against electric shock in the event of a failure of basic insulation
[SOU RCE: I EC 61 01 0-1 :201 0, 3. 6.2, I EC 60050-1 95: 1 998, 1 95-06-07, modified – as in
I EC 61 01 0-1 ]
– 26 –
I EC 62052-31 :201 5 © I EC 201 5
3. 6. 5
d o u b l e i n s u l a ti o n
insulation com prising both basic insulation and supplem entary insulation
[SOU RCE: I EC 60050-1 95: 1 998, 1 95-06-08]
3. 6. 6
re i n fo rc e d
i n su l ati on
insulation which provides protection against electric shock not less than that provided by
double insulation
Note 1 to entry: Rei nforced i nsulation m ay be com posed of several l ayers, which cann ot be tested sing ly as
supplem entary insul ation or basic insulation.
[SOU RCE: I EC 61 01 0-1 :201 0, 3. 6.4, I EC 60050-1 95: 1 998, 1 95-06-09, modified – as in
I EC 61 01 0-1 ]
3. 6. 7
cl a s s I
eq u i pm en t
p ro t e c t i v e c l a s s I
eq u i pm en t
equipment with basic insulation as provision for basic protection against electric shock and
protective bonding as provision for fault protection, such that conductive parts on the outside
of the equipment case cannot become live in the event of a failure of the basic insulation
[SOU RCE: I EC 60255-27: 201 3, 3. 7]
3. 6. 8
cl a s s I I e q u i p m e n t
p ro t e c t i v e c l a s s I I
equipm ent with:
•
•
•
eq u i pm en t
basic insulation as provision for basic protection against electric shock, and
supplementary insulation as provision for fault protection; or
in which basic protection and fault protection are provided by reinforced insulation
Note 1 to entry: Th ere shoul d be n o provision for a protective conductor or reliance upon installation conditions
for safety purposes. I t is, however, possibl e to connect an earth con ductor to Class I I equipm ent for functional (for
exam ple, EMC) pu rposes.
[SOU RCE: I EC 60255-27: 201 3, 3. 8, I EC 60050: 2008, 851 . 1 5. 1 1 , m odified – The phrase
"against electrical shock" and a note to entry have been added while the reference to
IEC 61 1 40: 2001 , 7. 3 has been omitted ]
3. 6. 9
p o l l u ti o n
addition of foreign matter, solid, liquid or gaseous that can produce a permanent reduction of
dielectric strength or surface resistivity of the insulation
Note 1 to entry: I oni zed gases of a tem porary n atu re are n ot considered as to be a poll ution.
[SOU RCE: I EC 60050-442: 1 998, 442-01 -28]
3. 6. 1 0
p o l l u t i o n d e g re e
numeral characterizing the expected pollution of the m icro-environm ent
[SOU RCE: I EC 60050-581 : 2008, 581 -21 -07]
I EC 62052-31 :201 5 © I EC 201 5
– 27 –
3. 6. 1 1
poll u ti on d eg ree 1
no pollution or onl y dry, non-conductive pollution occurs, which has no influence
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 6. 7]
3. 6. 1 2
poll u ti on d eg ree 2
onl y non-conductive pollution occurs except that occasionall y a temporary conductivity caused
by condensation is expected
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 6. 8]
3. 6. 1 3
poll u ti on d eg ree 3
conductive pollution occurs, or dry, non-conductive pollution occurs which becomes
conductive due to condensation which is expected
Note 1 to entry: I n such conditions, eq uipm ent is norm ally protected agai nst exposure to direct sunli ght,
preci pitation, an d full win d pressure, but n eith er tem peratu re nor hum idity is controll ed.
[SOU RCE: I EC 61 01 0-1 : 201 0, 3. 6. 9]
3. 6. 1 4
mi cro-en vi ron m en t
imm ediate environment of the insulation which particularly influences the dim ensioning of the
creepage distances
[SOU RCE: I EC 60050-851 : 2008, 851 -1 5-1 6]
3. 6. 1 5
cl earan ce
distance between two conductive parts along a string stretched the shortest way between
these conductive parts
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-31 ]
3. 6. 1 6
creepag e d i stan ce
shortest distance along the surface of a solid insulating m aterial between two conductive
parts
[SOU RCE: I EC 60050-1 51 : 2001 , 1 51 -1 5-50]
3. 6. 1 7
sol id in su lation
solid insulating m aterial interposed between two conductive parts
[SOU RCE: I EC 60664-1 : 2007, 3. 4]
3. 6. 1 8
disru ptive d isch arg e
failure of insulation under electric stress, in which the discharge completely bridges the
insulation under test, reducing the voltage between electrodes to practically zero
Note 1 to entry: N on -sustain ed disrupti ve discharg e in wh ich the test obj ect is m om entaril y bridged by a spark or
arc m ay occur. Duri ng th ese events th e voltag e across the test object is m om entaril y red u ced to zero or to a very
sm all valu e. Dependi ng on the characteristics of th e test circu it an d th e test object, a recovery of d iel ectric strength
– 28 –
I EC 62052-31 :201 5 © I EC 201 5
m ay occur an d m ay even al low th e test voltag e to reach a h igher value. Such an event sh ould be i nterpreted as a
disru ptive discharg e.
Note 2 to entry: A disrupti ve discharge i n a solid diel ectric produces perm anent loss of di electric strength; in a
liqui d or gaseous di electric th e loss m ay be onl y tem porary.
[SOU RCE: I EC 60060-1 : 201 0, 3. 1 . 1 ]
3.6.1 9
sparkover
disruptive discharge that occurs in a gaseous or liquid dielectric
[SOU RCE: I EC 60060-1 : 201 0, 3. 1 . 2]
3.6.20
flashover
disruptive discharge that occurs over the surface of a dielectric in a gaseous or liquid
dielectric
[SOU RCE: I EC 60060-1 : 201 0, 3. 1 . 3]
3.6.21
puncture
disruptive discharge that occurs through a solid dielectric
[SOU RCE: I EC 60060-1 : 201 0, 3. 1 . 4]
3.6.22
extra-low-voltage
ELV
voltage not exceeding the relevant voltage lim it of band I specified in I EC 60449
Note 1 to entry: For the pu rposes of this standard, the ELV values are specified i n 6. 3.
[SOU RCE: I EC 60050-826: 2004, 826-1 2-30]
3.6.23
SELV system
electric system in which the voltage cannot exceed the value of extra-low voltage:
•
•
under norm al conditions; and
under single-fault conditions, including earth faults in other circuits
Note 1 to entry:
SELV is the abbreviati on for safety extra l ow voltag e.
[SOU RCE: I EC 60050-826: 2004, 826-1 2-31 ]
3.6.24
PELV system
electric system in which the voltage cannot exceed the value of extra-low voltage:
•
•
under normal conditions, and
under single-fault conditions, except earth faults in other circuits
Note 1 to entry:
PELV is the abbreviati on for protecti ve extra low voltage.
[SOU RCE: I EC 60050-826: 2004, 826-1 2-32]
I EC 62052-31 :201 5 © I EC 201 5
3.7
– 29 –
Terms related to switches of metering equipment
3.7.1
switch
mechanical switch
mechanical switching device capable of m aking, carrying and breaking currents under norm al
circuit conditions which may include specified operating overload conditions and also carrying
for a specified time currents under specified abnorm al circuit conditions such as those of short
circuit
Note 1 to entry: A switch m ay be capable of m aking but n ot breaking sh ort-circuit cu rrents.
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 4-1 0]
3.7.2
supply control switch
SCS
switch intended to control the suppl y to the prem ises
Note 1 to entry: I t com prises the contacts and the parts operati ng th e contacts, and it may incl ude a m eans for
m anual operation.
Note 2 to entry: The supply control switch shou ld not be confused with th e su ppl y si de protection d evice that
disconn ects the suppl y in th e case of an overcu rrent fault.
3.7.3
load control switch
LCS
switch intended to control loads within the prem ises
Note 1 to entry: I t com prises the contacts an d the parts operating the contacts.
3.7.4
auxiliary control switch
switch intended to control auxiliary devices
Note 1 to entry: I t com prises the contacts or thei r electron ic equi valent and the parts operating th e contacts.
[SOU RCE: I EC 62052-21 :2004, 3. 5. 3 and 3. 5. 4, merged and m odified – to m ake the definition
more general and to provide additional inform ation in the N ote]
3.7.5
maximum total current
Itot
r.m.s. value of the total current that all the switches of a stand-alone tariff- or load-control
equipment can carry continuousl y at the sam e tim e under specified conditions
[SOU RCE: I EC 62052-21 :2004, 3. 5.8, modified – “r.m .s” and “stand alone” added]
3.7.6
short-circuit current
over-current resulting from a short circuit due to a fault or an incorrect connection in an
electric circuit
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 1 -07]
3.7.7
prospective current < of a circuit with or without a switching device>
current that would flow in the circuit if it was replaced by a conductor of negli gible impedance
– 30 –
I EC 62052-31 :201 5 © I EC 201 5
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-01 , modified – N ote rem oved]
3. 7. 8
breaki n g cu rren t < of
a switching device or a fuse>
current in a pole of a switching device or in a fuse at the instant of initiation of the arc during a
breaking process
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-07]
3. 7. 9
breaki n g capaci ty < of
a switching device or a fuse>
value of prospective current that a switching device or a fuse is capable of breaking at a
stated voltage under prescribed conditions of use and behaviour
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-08, m odified – N otes removed]
3. 7. 1 0
maki n g capaci ty < of
a switching device or a fuse>
value of prospective current that a switching device is capable of m aking at a stated voltage
under prescribed conditions of use and beh aviour
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-09, m odified – N ote removed]
3. 7. 1 1
sh ort-ci rcu i t m aki n g capaci ty
making capacity for which the prescribed conditions include a short circuit at the terminals of
the switching device
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-1 0]
3. 7. 1 2
sh ort-ti m e wi th stan d cu rren t
current that a circuit or a switching device in the closed position can carry during a specified
short time under prescribed conditions of use and behaviour
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-1 7]
3. 7. 1 3
fu sed sh ort-ci rcu i t cu rren t
conditional short-circuit current when the current limiting device is a fuse
[SOU RCE: I EC 60050-441 : 1 984, 441 -1 7-21 ]
3. 7. 1 4
mi n i m u m swi tch ed cu rren t
sm allest current that a switch is able to make, carry and break at the rated breaking voltage
and under prescribed conditions
[SOU RCE: I EC 62055-31 :2005, 3. 5.1 , modified – paym ent meter” replaced by “switch”]
3. 7. 1 5
tri p-free m ech an i cal swi tch i n g d evi ce
mechanical switching device, the m oving contacts of which return to and remain in the open
position when the opening (i.e. tripping) operation is initiated after the initiation of the closing
operation, even if the closing comm and is maintained
I EC 62052-31 :201 5 © I EC 201 5
– 31 –
Note 1 to entry: To ensu re proper breakin g of the current which m ay have been establish ed, it m ay be necessary
that the contacts m om entarily reach the cl osed position.
Note 2 to entry: The wordi ng of I EC 60050-441 : 1 984, 441 -1 6-31 has been com pleted by addi ng "(i. e. tripping )"
since the openi ng operati on of a trip-free m echanical switchin g device is autom atically controlled.
[SOU RCE: I EC 60947-1 : 2007, 2. 4. 23]
4
Tests
4. 1
G en eral
NOTE This subcl ause is based I EC 61 01 0-1 : 201 0, 4. 1 .
Tests in this standard are type tests to be carried out on samples of equipm ent or parts. Their
onl y purpose is to check that the design and construction ensure conform ity with this
standard.
Annex I specifies routine tests to be performed by manufacturers on equipm ent which has
both hazardous live parts and accessible conductive parts.
The equipment shall at least m eet the requirements of this standard. I t is perm issible to
exceed the requirem ents. I f, in this standard, a lower lim it is specified for a conformity value,
then the equipment m ay dem onstrate a larger value. I f an upper limit is specified for a
conform ity value, the equipment may demonstrate a lower value.
Tests on sub-assem blies that meet the requirements of the relevant standards specified in
this standard, and are used in accordance with them , need not be repeated . H owever, subassemblies are exposed to the tests when fitted in the equipm ent. The com plete equipment
with the sub-assemblies fitted shall pass the tests.
See also Clause 1 3.
Co n form ity with
te s ts,
e xce p t
th e
th a t
re quire m e n ts o f th is s ta n da rd is ch e cke d b y ca rryin g o ut a ll a p p lica b le
a
te st
may
be
o m itte d
if
e xa m in a tio n
of
th e
e quip m e n t
and
docum e n ta tio n de m on stra te s co n clus ive ly th a t th e e quip m e n t wo uld p a ss th e te st.
de s ign
Te sts a re
ca rrie d o ut un de r b oth re fe re n ce te s t co n ditio n s (s e e 4. 3) a n d fa ult co n ditio n s (s e e 4. 4) .
Wh e re co n form ity sta te m e n ts in th is sta n da rd re q uire in sp e ctio n , th is m a y in clude e xa m in a tio n
of
th e
e quip m e n t
by
m e a s ure m e n t,
e xa m in a tion
of
th e
m a rkin gs
on
th e
e quip m e n t,
e xa m in a tio n o f th e in structio n s s up p lie d with th e e quip m e n t, e xa m in a tion o f th e da ta s h e e ts o f
th e m a te ria ls or com p o n e n ts from wh ich th e e quip m e n t is m a n ufa cture d,
e tc.
In e a ch ca s e ,
th e in sp e ctio n will e ith e r de m o n stra te th a t th e e q uip m e n t m e e ts th e a p p lica b le re quire m e n ts
of th e cla us e , or will in dica te th a t furth e r te s tin g is re quire d.
If,
wh e n ca rryin g o ut a con form ity te st,
th e re is a n y un ce rta in ty a b o ut th e e xa ct va lue of a n
a p p lie d or m e a sure d qua n tity (for e xa m p le , vo lta ge ) due to th e to le ra n ce :
a)
th e m a n ufa cture r s h o uld e n sure th a t a t le a st th e s p e cifie d te st va lue is a p p lie d;
b)
th e te st h o use sh o uld e n sure th a t n o m ore th a n th e s p e cifie d te st va lue is a p p lie d.
4. 2
Type test – seq u en ce of tests
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 4. 2.
The sequence of tests is optional unless otherwise specified. The equipment under test shall
be carefull y inspected after each test. I f the result of a test causes doubt whether an y earlier
tests would have been passed if the sequence had been reversed, these earlier tests shall be
repeated.
– 32 –
4.3
I EC 62052-31 :201 5 © I EC 201 5
Reference test conditions
4.3.1
Atmospheric conditions
NOTE 1 This subcl ause is based on I EC 60068-1 : 201 3, but with valu es taken from I EC 62052-1 1 : 2003.
The standard range of atm ospheric conditions for carrying out m easurements and tests shall
be as follows:
a) ambient tem perature: 1 5 °C to 25 °C;
I n countries with hot climates, the m anufacturer and the test laboratory m ay agree to keep
the am bient temperature between 20 °C to 30 °C.
b) relative humidity 45 % to 75 %;
c) atm ospheric pressure of 86 kPa to 1 06 kPa.
d) No hoar frost, dew, percolating water, rain, solar radiation, etc. shall be present.
I f the param eters to be m easured depend on temperature, pressure and/or humidity and the
law of dependence is unknown, the atm ospheric conditions for carrying out m easurements
and tests shall be as follows:
e) ambient tem perature: 23 °C ± 2 °C;
f) relative humidity 45 % to 55 %.
NOTE 2 The val ues are from I EC 60068-1 : 201 3, 4. 2, wi de tolerance for tem perature an d wi de rang e for hum idity.
4.3.2
4.3.2.1
State of the equipment
General
NOTE Subclause 4. 3. 2 is based on I EC 61 01 0-1 : 201 0, 4. 3. 2, m odified as appropri ate for m eteri ng.
Unless otherwise specified, each test shall be carried out on the equipm ent assembled for
norm al use, and under the least favourable combination of the conditions given in 4.3. 2. 2 to
4. 3. 2. 1 0. I n case of doubt, tests shall be performed in more than one com bination of
conditions.
To be able to perform som e tests, like testing in single fault condition, verification of
clearances and creepage distances by measurem ent, placing thermocouples, checking
corrosion, a specially prepared specimen m ay be needed and / or it may be necessary to cut
a permanentl y closed specim en open to verify the results.
4.3.2.2
Position of equipment
The equipm ent shall be m ounted in its norm al working position, including a m atching socket
where applicable and with an y ventilation unimpeded. Equipment intended to be built into a
wall, recess, cabinet, etc. , shall be installed as specified in the manufacturer's instructions.
See also 1 0. 4.
4.3.2.3
Plug-in modules
An y plug-in m odules that may be used with the equipm ent under test and / or batteries shall
be either connected or not connected.
NOTE Exam ples for plug -i n modul es are comm unication m od ules provided or recomm ended by the m anufacturer.
4.3.2.4
Covers and removable parts
Covers or parts which can be rem oved without using a tool shall be removed or not rem oved.
I EC 62052-31 :201 5 © I EC 201 5
4.3.2.5
– 33 –
Connection of the voltage and current circuits
The equipment shall be connected for its intended purpose, (i. e. together with a specified
matching socket where applicable), or not connected.
Unless otherwise specified, the least favourable conditions that may occur in real life
conditions shall be selected from the following as applicable:
a) the voltage circuits of m eters shall be either energized or not energized. When energized,
the voltage shall be between 80 % of the lowest reference voltage and 1 1 5 % of the
highest reference voltage. I f the permitted tolerance is higher, then the voltage shall be at
an y voltage in the operating range;
b) in the case of single-phase equipment, the voltage shall be connected with both norm al
and reverse polarity (line and neutral reversed);
c) in the case of three-phase equipment, one, two, or three phase voltages shall be
connected. When all three phase voltages are connected, then the voltages shall be
connected with both normal and reverse phase sequence;
d) the current circuits shall be loaded with a current up to Im ax or not loaded;
I n the case of pol yphase equipm ent, the current circuits shall carry a balanced load.
NOTE For su ppl y and load control switches, see 4. 3. 2. 6. For au xi liary control switches, see 4. 3. 2. 7.
e) equipment for tariff and load control shall be either energized or not energized. When
energized, the voltage shall be between 80 % of the lowest reference voltage and 1 1 5 %
of the highest reference voltage. I f the permitted tolerance is higher, then the voltage shall
be at an y voltage in the operating range;
f) in the case of equipment with a (separate) auxiliary power suppl y, the auxiliary suppl y
voltage shall be connected or not connected. I n the case of d.c. or single phase a. c.
auxiliary power supply, the voltage shall be connected with both normal or reverse polarity
if this latter is possible;
g) the frequency shall be any rated frequency.
4.3.2.6
Supply and load control switches
Unless otherwise specified, all supply control switches (SCSs) and load control switches
(LCSs) shall be in the closed position. When a SCS is closed, it shall carry a current equal to
Im ax . When a LCS is closed, it shall carry a current equal to its rated operational current Ie . I f
there are several LCSs present, the total current shall not be m ore than Itot .
NOTE 1 Switches m ay be con troll ed locally or rem otely and they m ay be operated locall y.
NOTE 2 For testing direct connected m eters equ ipped with SCSs see 6. 1 0. 6. For testi ng l oad control switches
see and 6. 1 0. 7.
4.3.2.7
Connection of the auxiliary circuits
Auxiliary input circuits shall be either connected to an y voltage within their rated operating
voltage range or not connected.
The rated load im pedance of auxiliary output circuits shall be either connected or not
connected.
Auxiliary control switches shall be either in the closed or in the open position. When an
auxiliary control switch is closed, it shall be loaded or not loaded with rated current.
4.3.2.8
Connection of batteries
I n the case of equipment equipped with a battery, if the m eans of connection perm its reversal,
the battery shall be connected with both reverse and normal polarity.
– 34 –
4. 3. 2. 9
I EC 62052-31 :201 5 © I EC 201 5
Protecti ve con d u ctor term i n al s
Protective conductor term inals, if an y, shall be connected to earth.
4. 3. 2. 1 0
Ph ysi cal token carri ers
Payment m eters equipped with ph ysical token carrier acceptors m ay be tested with the token
carrier (or m etallic test token carrier) inserted or not inserted unless explicitl y specified for
particular tests.
4. 3. 2. 1 1
Test cabl es
NOTE 1 This subclause d oes not appl y to install ation, which is general ly su bject to nati on al wiri ng regulati ons.
NOTE 2 This subclause is based on I EC 60947-1 : 2007, 8. 3. 3. 3. 4.
Test cables for connecting the current circuits, suppl y control switches and load control
switches shall be single core or stranded, suitable insulated cables with cross-sections as
given in Table 1 . The length of the test cables shall be:
•
•
1 m for cross-sections up to and including 35 mm 2 (or AWG 2);
2 m for cross-sections larger than 35 mm 2 (or AWG 2).
For the terminals of voltage circuits and auxiliary circuits the test cables shall be single core
or stranded, suitabl y insulated cables of 1 mm 2 , unless otherwise specified by the
m anufacturer.
I EC 62052-31 :201 5 © I EC 201 5
Tabl e 1
– 35 –
– T e s t c o p p e r c o n d u c t o rs fo r c u rre n t a n d
C o n d u c to r s i z e
a,
s wi tch
t e rm i n a l s
b
Ra n g e o f t e s t c u r re n t
C ro s s - s e c t i o n
S i ze
E q u i v a l e n t c ro s s - s e c t i o n
A
mm 2
AWG / kcm il
mm 2
(for si zes gi ven
in AWG / kcm il)
0 < I≤ 8
1 ,0
18
0, 82
8 < I≤ 12
1 ,5
16
1 ,3
12 < I≤ 15
2, 5
14
2, 1
1 5 < I ≤ 20
2, 5
12
3, 3
20 < I ≤ 25
4, 0
10
5, 3
25 < I ≤ 32
6, 0
10
5, 3
32 < I ≤ 50
10
8
8, 4
50 < I ≤ 65
16
6
1 3, 3
65 < I ≤ 85
25
4
21 , 2
85 < I ≤ 1 00
35
3
26, 7
1 00 < I ≤ 1 1 5
35
2
33, 6
1 1 5 < I ≤ 1 30
50
1
42, 4
1 30 < I ≤ 1 50
50
0
53, 5
1 50 < I ≤ 1 75
70
00
67, 4
1 75 < I ≤ 200
95
000
85
200 < I ≤ 225
95
0000
1 07, 2
225 < I ≤ 250
1 20
250 kcm il
1 27
250 < I ≤ 275
1 50
300 kcm il
1 52
275 < I ≤ 300
1 85
350 kcm il
1 77
300 < I ≤ 350
1 85
400 kcm il
203
350 < I ≤ 400
240
500 kcm il
253
NOTE This tabl e is based on I EC 60947-1 : 2007, Tabl e 1 an d Tabl e 9.
AWG: Am erican Wire Gau ge si ze.
Circul ar m ils: The stand ard uni t of a – large – wi re’s cross-sectional area.
kcm il: thousand circu lar m ils.
a
For conveni ence of testing an d with the m anufacturer’s con sent, sm aller cond uctors th an those gi ven for a
stated test current m ay be used.
b
Either of th e two cond uctors specified for a gi ven test current ran ge m ay be used.
Unless otherwise specified by the m anufacturer, stranded cables shall be term inated by fitting
cable end ferrules and they shall be correctly crim ped with an appropriate crim ping tool. All
contact surfaces shall be free of oxide layers.
NOTE 3 See DI N 46228-1 : 1 992-08
sle e ve s with o ut p la stic sle e ve .
A de re n dh ülse n ;
Ro h rfo rm
ohne
Kun sts to ffh üls e
. En glish title:
Tub ula r e n d-
Term inal screws, where used, shall be tightened according to the manufacturer’s instructions.
4. 3 . 2 . 1 2
I n fo rm a t i o n
on
te s ts
NOTE 1 The followin g is based on I EC 60255-27: 201 3, 1 0. 4.
– 36 –
I EC 62052-31 :201 5 © I EC 201 5
The following data for each test to be conducted shall be available from the manufacturer on
request:
•
•
•
the type, cross-sectional area, length and termination of connecting cables, if these can
affect the type test results, for example temperature rise. I f these are different from the
values specified in Table 1 , the reasons shall be given;
the position of the equipment where relevant;
the state of the equipm ent;
NOTE 2 This inclu des voltag es and currents appl ied to the term inals, parts fitted or not, position of switches
etc.
•
m easurement uncertainty for all measurem ent results.
Where applicable, the data shall include:
•
•
•
initial measurement;
m easurement during the individual test;
final m easurement.
4. 4
Testi n g i n si n g l e fau l t con d i ti on
4. 4. 1
G en eral
NOTE Subclause 4. 4 is based on I EC 61 01 0-1 : 201 0, 4. 4, modified as applicable for m eteri ng.
The m anufacturer may provide guidance to the test laboratory on how to perform tests in
single fault condition. The following general guidelines and requirements appl y.
a) examination of the equipment and its circuit diagram will generally show the fault
conditions which are liable to result in hazards and which, therefore, shall be applied;
b) fault tests shall be made as specified for checking conform ity, unless it can be
demonstrated that no hazard could arise from a particular fault condition;
c) the equipment shall be operated under the least favourable combination of reference test
conditions (see 4. 3). These com binations m ay be different for different faults an d they
shall be recorded for each test.
4. 4. 2
4. 4. 2. 1
Appl i cati on of fau l t con d i ti on s
Gen eral
Fault conditions shall include those specified in 4.4. 2. 2 to 4. 4. 2. 8. They shall be applied one
at a tim e and shall be applied in turn in an y convenient order. M ultiple sim ultaneous faults
shall not be applied unless they are a consequence of an applied fault.
After each application of a fault condition, the equipm ent or part shall pass the applicable
tests of 4. 4. 4.
4. 4. 2. 2
Protecti ve i m ped an ce
The following requirem ents appl y:
a) if a protective impedance is form ed by a com bination of com ponents, and unless each
com ponent is certified to fail in an open circuit state, each com ponent shall be shortcircuited or disconnected, whichever is less favourable;
b) if a protective impedance is formed by the com bination of basic insulation and a current or
voltage limiting device, both the basic insulation and the current or voltage limiting device
shall be subj ected to single faults, applied one at a time. Basic insulation shall be bridged
and the current or voltage lim iting device shall be short-circuited or disconnected,
whichever is less favourable;
I EC 62052-31 :201 5 © I EC 201 5
– 37 –
c) if a protective impedance is form ed with a single component that m eets the requirements
of 6. 5. 4, it need not be short-circuited or disconnected.
4.4.2.3
Equ ipment or parts for short-term or intermittent operation
These shall be operated continuousl y if continuous operation could occur in a single fault
condition.
NOTE I ndi vid ual parts incl ude relays an d oth er electrom agnetic devices.
4.4.2.4
4.4.2.4.1
Transformers
General
NOTE Subclause 4. 4. 2. 4 appl ies onl y to transform ers used within the m eterin g equi pm ent.
Transform ers shall be tested as specified in 4. 4. 2.4. 2 to 4.4. 2. 4. 4.
A transformer dam aged during one test m ay be repaired or replaced before the next test.
4.4.2.4.2
Short circuit test for voltage transformers
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 4. 4. 2. 7. 2.
Each untapped output winding, and each section of a tapped output winding, which is loaded
in normal use, shall be tested in turn, one at a tim e, to simulate short circuits in the load.
Overcurrent protection devices remain fitted during the test. All other windings are loaded or
not loaded; whichever load condition of norm al use is less favourable.
4.4.2.4.3
Overload
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 4. 4. 2. 7. 3.
Each untapped output winding, and each section of a tapped output winding, is overloaded in
turn one at a tim e. The other windings are loaded or not loaded whichever load condition of
norm al use is less favourable. I f an y overloads arise from testing in the single fault conditions
of 4. 4, secondary windings shall be subjected to those overloads.
Overloading is carried out by connecting a variable resistor across the winding. The resistor is
adj usted as quickl y as possible and readj usted, if necessary, after 1 min to m aintain the
applicable overload. N o further readj ustments are then perm itted.
I f overcurrent protection is provided by a current-breaking device, the overload test current is
the maximum current which the overcurrent protection device is just capable of passing for
1 h. Before the test, the device is replaced by a link with negligible im pedance. I f this value
cannot be derived from the specification, it is to be established by test.
For equipm ent in which the output voltage is designed to collapse when a specified overload
current is reached, the overload is slowly increased to a point just before the point which
causes the output voltage to collapse.
I n all other cases, the loading is the m axim um power output obtainable from the transformer.
4.4.2.4.4
Open circuit of current transformers
The secondary side of (a) current transform er(s) (CTs) shall be open-circuited.
I f this condition cannot occur in practice, this test may be omitted. For exam ple, this test may
be omitted for potted CTs soldered and m echanicall y secured to the printed wiring board, or
for CTs with their secondary side connected to the printed wiring board by m echanicall y
secured cables, such that solder j oints are protected from mechanical stress.
– 38 –
4. 4. 2 . 5
E q u i p m e n t wi th
I EC 62052-31 :201 5 © I EC 201 5
a u x i l i a ry s u p p l y
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 4. 4. 2. 9.
Equipment designed to be operated with an auxiliary suppl y shall be connected to that suppl y
or not, whichever is less favourable.
4. 4. 2 . 6
M a i n s - c i rc u i t s a n d h a z a rd o u s v o l t a g e n o n - m a i n s - c i rc u i t s
NOTE 1 This subcl ause is based on I EC 60255-27: 201 3, 5. 2. 2. 6.
Single fault conditions shall be applied by open-circuiting or short-circuiting com ponents in
mains-circuits and hazardous voltage non-m ains-circuits, within the equipm ent, where these
may create a risk of electric shock or fire.
NOTE 2 A single fault conditi on test for varistors is un der consideration.
4. 4. 2 . 7
O v e rl o a d s
NOTE 1 This subclause is based on I EC 60255-27: 201 3, 5. 2. 2. 7.
NOTE 2 This subclause refers to all au xili ary circuits, an d n ot to the m ain current and l oad control ci rcuits.
Single-fault conditions shall be applied where a circuit or com ponent overload m ay create a
fire or electric shock hazard. This includes connection of the most unfavourable load
impedances to term inals and connectors which deliver power or sign al outputs from the
equipm ent.
I t is perm itted to use fusible links, overcurrent protection devices and the like to provide
adequate protection.
Where there are m ultiple outlets with the same internal circuitry, the single-fault test can be
limited to one outlet only.
4. 4. 2 . 8
I n t e rm i t t e n t l y ra t e d
re s i s t o rs
NOTE This subcl ause is based on I EC 60255-27: 201 3, 5. 2. 2. 8.
Continuous dissipation in resistors designed for in term ittent dissipation shall be considered
under the single fault conditions assessment.
4. 4. 2 . 9
D o u b l e i n s u l ati o n
I f double insulation is applied then it shall be verified by short circuiting the basic and then the
supplem entary insulation, one at a tim e. I t shall be ascertained that basic insulation is
m aintained.
For components bridging insulation, see 1 3. 4.
4. 4. 3
D u ra t i o n
o f te s t s
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 4. 4. 3. 1 .
The equipm ent shall be operated until further change as a result of the applied fault is
unlikel y. Each test is norm all y lim ited to 1 h since a secondary fault arising from a single fault
condition will usuall y manifest itself within that time. I f there is an indication that a hazard of
electric shock, spread of fire or injury to persons m ay eventuall y occur, the test shall be
continued for 4 h unless one of these hazard s arises before that.
4. 4. 4
C o n fo rm i t y a ft e r a p p l i c a t i o n
o f fa u l t c o n d i t i o n s
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0 4. 4. 4, m utatis m utandis.
I EC 62052-31 :201 5 © I EC 201 5
4. 4. 4. 1
– 39 –
G e n e ra l
Co n form ity with th e re quire m e n ts fo r p ro te ction a ga in st e le ctric s h o ck a fte r th e a p p lica tion o f
sin gle fa ults is ch e cke d a s fo llo ws:
a)
b y m a kin g th e m e a sure m e n ts o f 6. 3. 3 to ch e ck th a t n o a cce ssib le co n ductive p a rts h a ve
b e co m e h a za rdo us live ;
b)
b y p e rfo rm in g a volta ge te st on doub le in s ula tio n or re in force d in sula tio n to ch e ck th a t th e
p ro te ction is still a t le a st a t th e le ve l o f b a s ic in s ula tio n .
sp e cifie d
in
6. 1 0. 4 . 3. 3
with o ut
h um idity
p re co n dition in g,
Th e vo lta ge te s ts a re m a de a s
with
a
te st
vo lta ge
for
b a sic
in sula tio n ;
c)
b y m e a s urin g th e te m p e ra ture of tra n s form e r win din gs if th e p ro te ctio n a ga in st e le ctrica l
h a za rds is a ch ie ve d b y do ub le in sula tio n
or re in force d in sula tio n
with in
th e
tra n sfo rm e r.
Th e te m p e ra ture s o f Ta b le 33 s h a ll n ot b e e xce e de d.
4. 4. 4. 2
T e m p e ra t u re
Co n form ity with th e re quire m e n ts for p rote ctio n a ga in s t e xce ssive te m p e ra ture rise is ch e cke d
b y de te rm in in g th e te m p e ra ture o f th e a cce ssib le surfa ce of th e e n closure a n d of th e p a rts .
Se e Cla use 1 0.
4. 4. 4. 3
S p re a d o f fi re
Co n form ity
with
p la cin g th e
e quip m e n t o n
th e
re q uire m e n ts
wh ite
e q uip m e n t with ch e e se cloth .
fo r
p ro te ction
a ga in s t
tiss ue -p a p e r cove rin g a
No m o lte n m e ta l,
th e
sp re a d
o f fire
so ftwoo d s urfa ce
b urn in g in sula tio n ,
is
ch e cke d
by
a n d cove rin g th e
fla m in g p a rticle s ,
e tc. sh a ll
fa ll o n th e s urfa ce o n wh ich th e e quip m e n t is p la ce d a n d th ere s h a ll b e n o ch a rrin g, glo win g,
or fla m in g of th e tiss ue p a p e r o r ch e e s e clo th . Me ltin g o f in s ula tion m a te ria l sh a ll b e ign o re d if
n o h a za rd co uld a ris e .
4. 4. 4. 4
O t h e r h a z a rd s
Co n form ity with o th e r re quire m e n ts for p rote ctio n a ga in st h a za rds is ch e cke d a s sp e cifie d in
Cla use s 7 to 1 4 .
5
5. 1
I n fo rm a t i o n a n d m a rk i n g re q u i re m e n t s
G e n e ra l
NOTE Clause 5 is based on the foll owi ng references:
I EC 62052-1 1 : 2003, 5. 1 2, I EC 62052-21 : 2004, 5. 1 2, I EC 62055-31 : 2005, 5. 1 3;
•
I EC 61 01 0-1 : 201 0 Clause 5; and
•
I EC 62477-1 : 201 2 Clause 6.
•
The purpose of this Clause 5 is to define the safety-related inform ation necessary for the safe
selection, installation and comm issioning, for use, and for m aintenance of metering
equipment. The required inform ation is presented in Table 2 showing where the inform ation
shall be provided. References to explanatory and technical subclauses are given.
Unless otherwise stated, the requirements of this Clause shall appl y to all metering equipment
in the scope of this standard.
All information shall be in an appropriate language, and docum ents shall have identification
references.
– 40 –
T a b l e 2 – I n fo rm a t i o n
I EC 62052-31 :201 5 © I EC 201 5
re q u i re m e n t s
L o c a ti o n
a,
b
Te c h n i c a l
S u bcl au se
s u b cl au s e
I n fo rm a t i o n
re fe re n c e
C
D
P
IM
UM
MM
re fe re n c e
M
M
M
M
–
O
O
O
O
–
M
M
M
M
5. 3
F o r s e l e cti o n
General information
Manufactu rer's nam e or trad e m ark
M
Desig nation of functi on
O
Type
M
Space for approval m ark
M
Serial num ber
5. 3. 2
Protective class
M
M
O
–
O
O
M
–
M
M
Rated im pulse voltag e
–
6. 7. 1 . 3
M
M
M
M
6. 7. 3. 1
Annex K
Utilization categ ory (UC)
for di rect conn ected m eters onl y
M
6. 9. 8. 3
M
M
M
Envi ronm ental conditi ons, storage
O
M
M
–
Envi ronm ental conditi ons, operation,
includi ng
O
M
M
1 .4
6. 9. 8. 4
•
m echanical conditi ons
O
O
O
•
clim atic conditions
O
O
O
•
altitud e
O
O
O
•
location (d ry or wet)
O
O
O
M
11
I P rating
O
M
M
Reference to stand ards
M
M
M
M
M
–
M
M
M
–
–
Reference to instructions
5. 3. 3
Fo r me te rs
Reference voltag e(s)
M
M
M
M
Reference current and cu rrent ran ge
M
M
M
M
M
M
M
M
Fo r s ta n d- a lo n e ta riff a n d lo a d co n tro l
e quip m e n t
5. 3. 4
Suppl y voltage(s)
–
Sup p ly co n tro l switch e s
The rated operati ng voltage:
Ue ;
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
O
M
M
M
M
M
M
M
M
L o a d co n tro l switch e s
The rated operati ng voltage: Ue ;
The rated operati ng cu rrent: Ie ;
The m axim um perm anent total current
of the load control switch es: Ito t ;
F o r i n s ta l l a ti o n
an d
com m i s s i on i n g
Han dlin g and m ountin g
Enclosure
Con nection requi rem ents
Con nection an d wi ring di agram s
Mai ns term inals
Au xili ary term inals
Con nectin g cabl es
I solation from the suppl y
5. 3. 5
5. 4
5. 4. 2
5. 4. 3
5. 4. 4
5. 4. 4. 2
5. 4. 4. 3
5. 4. 4. 4
5. 4. 4. 5
5. 4. 4. 6
M
M
M
M
M
M
M
M
M
M
6. 9. 8
–
6. 9. 4, 1 0. 1
–
–
6. 9. 7
–
6. 9. 7. 2
–
I EC 62052-31 :201 5 © I EC 201 5
– 41 –
L o c a ti o n
a,
b
Te c h n i c a l
S u bcl au se
s u b cl au s e
I n fo rm a t i o n
re fe re n c e
Protection requi rem ents
Protective class and earthin g
External protection d evices
Au xil i ary power suppl y
Suppl y for external d evices
Batteries
Self-consum ption
Com m issioning
For u se
General
Display, push buttons an d other controls
Switch es
Con nection to user’s eq uipm en t
External protection d evices
Cleanin g
F o r m a i n te n a n ce
5. 4. 5
5. 4. 5. 1
5. 4. 5. 2
5. 4. 6
5. 4. 7
5. 4. 8
5. 4. 9
5. 4. 1 0
5. 5
5. 5. 1
5. 5. 2
5. 5. 3
5. 5. 4
5. 5. 5
5. 5. 6
5. 6
5. 6
C
D
P
M
M
M
M
IM
M
M
M
M
M
M
M
M
M
M
UM
O
M
M
M
M
M
M
MM
re fe re n c e
M
M
M
M
M
M
M
M
–
6. 5. 2
–
–
–
12
M
–
–
1 0. 1
6. 9. 8
6. 8
–
5. 2. 2
–
Mai ntenance i nstructions
M
Location:
C = Case. These m arkings m ay appear on n am eplate(s) or m ay be carri ed by the m eter cover(s) in a
perm anent m anner. Connecti on diagram s m ay be m arked on the un derside of the term inal cover(s).
D = Display;
P = Packaging;
I M = I nstruction m anu al. U M = User m anual. M M = Mai nten ance m anual.
b
M = Mandatory, O = Opti on al
c
The i nstallati on, user an d m ainten ance m anu als m ay be com bined as appropriate an d, if acceptabl e to th e
custom er, m ay be suppl ied i n electronic form at. When m ore than one of an y prod uct is supplied to a single
custom er, it is not necessary to suppl y a m anu al with each u nit, if acceptabl e to the custom er.
a
5. 2
5. 2 . 1
Label s ,
si g n s an d
sign als
G e n e ra l
Labelling shall be in accordance with good ergonomic principles so that notices, controls,
indications, test facilities etc. are sensibl y placed and logicall y grouped to facilitate correct
and unambiguous identification.
NOTE The term “Label” is u sed h ere i n a g eneral sense. Labels are real ized usin g various techn ologies, e. g.
m oulding, laser m arking an d engraving, on adhesi ve l abels, etc.
The size of warning markings shall be as follows:
a) symbols shall be at least 2, 75 m m high. Text shall be at least 1 ,5 m m high and contrast in
colour with the background;
b) sym bols or text m oulded, stamped or engraved in a m aterial shall be at least 2, 0 mm high.
I f not contrasting in colour, they shall have a depth or raised height of at least 0, 5 m m.
All safety related equipm ent labels should be placed in such a way that they will:
c) be readil y visible to the intended viewer; and
d) alert the viewer to an y hazard in time to take appropriate action.
Where a hazard is present after the removal of a cover, a warning label shall be placed on the
equipment. The label shall be visible before the cover is rem oved.
– 42 –
S AF E T Y
M AR KI N G
S H AL L
WH E RE VE R
POSSI BLE
I EC 62052-31 :201 5 © I EC 201 5
T AK E
P RE C E D E N C E
O VE R
AN Y
F U N C T I O N AL M AR KI N G S .
Letter symbols for quantities and units shall be as specified in I EC 60027-1 .
Graphic sym bols shall conform to I EC 62053-52, I EC 6041 7-DB-1 2M , I EC 6061 7-DB-1 2M,
and I SO 7000 as appropriate. I EC 6041 7-DB-1 2M and I SO 7000 symbols that may be used on
metering equipm ent are shown in Table 3. Symbols not shown in these standards shall be
explained where used. There are no colour requirements for sym bols.
The documentation of the m etering equipm ent shall include a statement that it shall be
consulted in all cases where symbol 1 4 of Table 3 is marked, in order to find out the nature of
the potential hazards and an y actions which have to be taken to avoid them.
Labels shall:
be conspicuous, legible and durable;
be concise and unambiguous;
state the hazards involved and give ways in which risks can be reduced.
•
•
•
Tabl e 3 – I E C 6 0 41 7 s ym b ol s an d
th at m a y b e u s e d
N u m ber
S ym b o l
on
m e t e ri n g
Re fe re n c e
1
2
3
4
D e s c ri p t i o n
Not
Not
Not
Not
used
used
used
used
5a
I EC 6041 7-501 7
Earth; g round
5b
I EC 6041 7-501 8
Function al earth ing; fu nction al
groundin g (US) a
6
I EC 6041 7-501 9
Protective earth;
protective groun d
7
I EC 6041 7-5020
Fram e or chassis
8
9
10
Not used
Not used
Not used
11
I EC 6041 7-51 72
Protective class I I equipm ent
(Doubl e or reinforced i nsulati on)
12
I EC 6041 7-5036
Dan gerous voltage
13
a
I SO 7000
eq u i pm en t
Not used
14
I SO 7000-0434B
Cauti on, refer to accom pan yin g
docum ents.
15
I SO 7000-1 641
Operator's m anual;
operati ng instructions
There m ay be national differen ces concerni ng th e use of this sym bol.
I EC 62052-31 :201 5 © I EC 201 5
– 43 –
When instructing the person(s) concerned as to:
: the wording should include “no”, “do not”, or “prohibited”;
: the wording should include “shall”, or “must”;
the wording should include “caution”, “warning”, or “danger”, as
appropriate;
: the wording should include th e noun appropriate to the
safety device.
•
wh at to avo i d
•
wh at to d o
•
t h e n a t u re o f t h e h a z a rd :
•
th e
n a t u re
of
s a fe
co n d i ti o n s
Safety signs shall com pl y with I SO 3864-1 .
The signal words indicated hereinafter shall be used and the following hierarch y respected:
to call attention to a high risk, for example: “H igh voltage”;
to call attention to a medium risk, for example: “This surface can be hot”;
to call attention to a low risk, for example; “Som e of the tests specified in this
standard involve the use of processes im posing risks on persons concerned.”
•
D AN G E R
•
W AR N I N G
•
C AU T I O N
Danger, warning and caution markings on the metering equipment shall be prefixed with the
word “DANGER”, “WARNI NG”, or “CAUTI ON” as appropriate in letters not less than 3, 2 mm
high. The remaining letters of such m arkings shall be not less than 1 , 6 mm high.
Co n form ity is ch e cke d b y in s p e ctio n .
5. 2 . 2
D u ra b i l i t y o f m a rk i n g s
When feasible, placement of the label should provide protection from foreseeable dam age,
fading, or visual obstruction caused by abrasion, ultraviolet light, or substances such as
lubricants, chem icals and dirt.
An adhesive that is permanent shall be used to secure adhesive labels.
Co n form ity
is
ch e cke d
by
p e rform in g
th e
fo llo win g
te st
fo r
dura b ility
of m a rkin gs
on
th e
outs ide o f th e e q uip m e n t. Th e m a rkin gs a re rub b e d b y h a n d, with o ut un due p re ssure , for 30 s
with
a
cloth
s oa ke d with
e a ch
cle a n in g
a ge n t re com m e n de d b y th e
m a n ufa cture r a n d with
70 % iso p rop yl a lco h o l.
A fte r th e a b ove tre a tm e n t th e m a rkin gs s h a ll b e cle a rly le gib le a n d a dh e sive la b e ls s h a ll n o t
h a ve worke d lo os e or b e com e curle d a t th e e dge s .
5. 3
I n fo rm a t i o n
5. 3 . 1
fo r s e l e c t i o n
G e n e ra l
Metering equipment shall be provided with inform ation relating to its function, electrical
characteristics and intended environm ent, so that its fitness for purpose can be determined.
This inform ation includes, but is not limited to the information specified in 5. 3. 2 to 5. 3. 5 that
follow here.
5. 3. 2
•
•
G e n e ra l
i n fo rm a t i o n
m anufacturer's name or trade mark;
designation of function and type. Designation of the function shall be preferabl y in local
language;
NOTE 1 Exam ples for function are “kWh m eter”, “Sm art m eter”, “Tim e switch ”, “Ripple control recei ver”.
•
space for approval mark;
– 44 –
•
I EC 62052-31 :201 5 © I EC 201 5
serial num ber. The serial number shall uniquel y identify the metering equipm ent. I f it is
located on a removable cover, the number shall also be marked on the base of the
m etering equipm ent or stored in its non-volatile m emory and displayed on its electronic
display;
NOTE 2 M eterin g eq uipm ent often carry ad ditional i dentifi ers, like bar cod es, location identifiers, etc.
•
•
•
•
•
•
•
•
protective class;
rated impulse voltage;
utilization category (U C), for direct connected meters onl y;
environm ental conditions for storage;
environm ental conditions, operation: the conditions under which the metering equipm ent is
designed to be used. This shall identify:
– m echanical conditions (vibration, shock);
– climatic conditions (indoor / outdoor, temperature, hum idity, altitude, pollution, ultraviolet etc.);
– altitude where relevant;
– location – dry or wet – where relevant;
I P rating. See also 5. 4. 3 and Clause 1 1 ;
reference to the relevant product standard(s);
reference to instructions for installation (I M), operation (U M) and m aintenance (MM).
5. 3 . 3
•
•
re l a t e d
t o m e t e rs / m e t e ri n g
el em en ts
reference voltage(s) and voltage range(s) as specified in the relevant product standards;
reference current and current range as specified in the relevant product standards.
5. 3 . 4
•
I n fo rm a t i o n
I n fo rm a t i o n
re l a t e d
t o s t a n d - a l o n e t a ri ff- a n d
l o ad
c o n t ro l
eq u i pm en t
suppl y voltage reference voltage(s) and voltage range(s) as specified in the relevant
product standards.
5. 3 . 5
I n fo rm a t i o n
re l a t e d
t o s u p p l y c o n t ro l
and
l oad
c o n t ro l
s wi tc h e s
For suppl y control switches (SCSs) the following information shall be provided:
•
the rated operating voltage: Ue if different from the reference voltage of the m eter;
For load control switches (LCSs) the following inform ation shall be provided:
•
•
•
the rated operating voltage Ue if different from the reference voltage of metering
equipm ent;
the rated operating current Ie . The marking shall be provided at or near the load side
term inal of the circuit switched. I f the load switch has independent terminals, the m arking
shall appear in square brackets;
the m axim um perm anent total current of the load control switches at the m axim um
operating tem perature: Itot .
See also 6.9.8. 4 and 6. 9. 8. 5.
5. 4
5. 4. 1
I n fo rm a t i o n
fo r i n s t a l l a t i o n
an d
com m i s s i o n i n g
G e n e ra l
Safe and reliable installation is the responsibility of the installer. The manufacturer of
metering equipment shall provide inform ation to support this task. This inform ation shall be
unam biguous, and may be in diagramm atic form.
I EC 62052-31 :201 5 © I EC 201 5
– 45 –
Since an y electrical equipment can be installed or operated in such a m anner that hazardous
conditions can occur, com pliance with the requirements of this standard does not by itself
assure a safe installation. However, when equipm ent com pl ying with those requirements is
properl y selected and correctl y installed, commissioned and used, the hazards will be
minim ized.
5.4.2
Handling and mounting
I n order to prevent injury or damage, the installation docum ents shall include warnings of an y
hazards which can be experienced during installation. Where necessary, instructions shall be
provided for:
•
•
•
•
•
•
packing and unpacking;
m oving;
lifting;
strength and rigidity of m ounting surface;
fastening;
provision of adequate access for operation, adjustment and maintenance.
Optionall y, handling and mounting instructions can be provided on the packaging.
Conformity is checked by inspection.
5.4.3
Enclosu re
Information shall be provided on whether the m etering equipment is intended for indoor or
outdoor use.
If metering equipm ent is designed for use in an enclosure like a meter cabinet, this shall be
stated.
When metering equipment surfaces at tem peratures exceeding 90 o C are close to m ounting
surfaces, the installation manual shall contain a warning to consider the com bustibility of the
m ounting surface.
I n norm al operation, such condition may occur if metering equipm ent is used under extrem el y
hot clim atic conditions.
Conformity is checked by inspection.
5.4.4
5.4.4.1
Connection
General
I nform ation shall be provided to enable the installer to m ake safe electrical connections to the
m etering equipm ent. This shall include inform ation for protection against hazards (for
example, electric shock or availability of energ y) that may be encountered during installation.
5.4.4.2
Connection diagrams
I f necessary for safety, the connection diagram shall show where the suppl y control and load
control switches and the internal power suppl y are connected.
Where there is insufficient space, sym bol 1 5 of Table 3 m ay be used.
Conformity is checked by inspection.
– 46 –
5.4.4.3
I EC 62052-31 :201 5 © I EC 201 5
Mains terminals
Mains term inals com prise the term inals of the current and voltage circuits of the meter and
the term inals of the supply and/or load control switches.
For each m ains term inal, the maxim um rating of the term inal at which it has been designed to
operate while maintaining safety shall be given.
Where term inals have the same rating the marking does not have to be repeated.
Terminals rated at the maximum current of the m eter do not have to be marked.
5.4.4.4
Auxiliary terminals
Terminals and connectors of auxiliary circuits shall be readily identifiable by the equipment
markings. I ndividual terminals within a connector shall be unambiguousl y identifiable.
The following information shall be provided in the docum entation as applicable:
•
the function(s): e. g. pulse input/output, control input/output;
NOTE Som e I /O lines have a programm able function.
•
•
•
•
•
•
•
•
•
the kind of the circuit(s), e. g. optocoupler, relay, solid state relay;
kind of voltage (a. c. or d.c.), nominal, m inim um and m axim um voltages. I f the control
voltage of (a) control input(s) or output(s) is different from the reference voltage of the
m etering equipment, this shall be specified on the nam e-plate or on a separate label;
nominal, m inim um, continuous and short tim e maximum current as applicable;
the burden;
nom inal and m axim um frequency as applicable;
insulation from other circuits, insulation voltage, an y other relevant inform ation for testi ng;
in the case of inputs, inform ation on clam ping of overvoltages;
in the case of output relays:
– type of the contact(s): norm ally open, norm all y closed, changeover;
– contact impedance;
– withstand voltage across open contacts;
– duty cycle;
– num ber of operating cycles;
an y other safety related inform ation.
Conformity is checked by inspection.
5.4.4.5
Connecting cables
NOTE Gen erall y, national regulati ons are in pl ace concern ing el ectrical install ations. These regulati ons, am ong
others, specify the type an d size of the con nection cabl es to be used.
Metering equipm ent shall be suitabl y marked to warn the installer to consult the local
regulations and the installation m anual before installation. The m arking shall be adj acent to
the term inals and visible both before and during connection. The sym bol 1 5 of Table 3 is an
acceptable marking.
The installation manual shall contain recom mendations for the type, size, voltage and
tem perature rating of connecting cables to be used for each terminal, including the protective
earth terminal if present. For the current term inals, the minimum size of the connecting cables
I EC 62052-31 :201 5 © I EC 201 5
– 47 –
which can be safel y accomm odated shall also be specified. Recomm ended cable term inations
and tightening torque values shall be also specified where applicable.
Conformity is checked by inspection.
5. 4. 4. 6
I s o l a t i o n fro m t h e s u p p l y
Recomm endations shall be provided on how suppl y to the metering equipment can be isolated
before installation and rem oval.
I f it is possible to install the meter wi thout isolating the suppl y, i. e. on live network, then
appropriate instructions and safety warnings shall be provided.
Specific aspects and safety hazards related to external voltage and current transform ers,
auxiliary supplies and local generation shall be covered.
Conformity is checked by inspection.
5. 4. 5
5. 4. 5 . 1
P ro t e c t i o n
P ro t e c t i v e c l a s s a n d
e a rt h i n g
Equipm ent of protective class I I – full y protected by double insulation or reinforced insulation
– shall be marked with sym bol 1 1 of Table 3. Equipm ent which is onl y partiall y protected by
double insulation or reinforced insulation shall not be m arked with sym bol 1 1 .
Where equipment of protective class I I has provision for the con nection of an earthing
conductor for functional reasons, it shall be marked with sym bol 5b) of Table 3.
For m etering equipm ent of protective class I , the protective conductor terminal shall be
marked with the sym bol 6 of Table 3. The sym bol shall be placed on the term inal or close to
it.
The installation m anual shall include a statem ent that the protective earth connector shall be
connected first and that it shall not be rem oved until suppl y to the m eter is fully isolated.
Conformity is checked by inspection.
5. 4. 5 . 2
E xt e rn a l p ro t e c t i o n
d evi ces
NOTE 1 Generall y, there exi st nation al reg ulati ons coverin g the protection of th e electri cal instal l ation. These
reg ulati ons, am ong others, specify the kind, rating and characteristics of external protection devices, for exam ple
circuit breakers, fuses, fuse cutouts. Th eir selection d epen ds on the l ocation where the m etering eq uipm ent is
installed.
Metering equipm ent shall be suitabl y m arked to warn the installer to consult local regulations
and the installation m anual for the necessary protection requirem ents before installation. The
marking shall be adjacent to the terminals and visible both before and during connection
beside the terminals. Symbol 1 5 of Table 3 is an acceptable marking.
The installation m anual shall contain recomm endations for the suppl y side external protection
devices to be used. I n the case of voltage transformer connected m eters, this shall include
recom mendations for protecting the voltage circuit.
NOTE 2 When local generati on is present, “suppl y side protection” com prises both protection from supply from
the distri buti on n etwork an d protection from supply from local gen erati on.
The installation manual shall also contain a statement that the installer is responsible for coordinating the rating and the characteristics of the supply side overcurrent protection devices
– 48 –
I EC 62052-31 :201 5 © I EC 201 5
with the maximum current rating and, in the case of direct connected meters, with the U C
rating of the metering equipment. See also 6. 9. 8. 3.
Conformity is checked by inspection.
5. 4. 6
Au xil i ary power su ppl y
If an auxiliary suppl y input is present, the following inform ation shall be provided:
•
•
•
the kind of auxiliary suppl y voltage (a. c. and/or d.c.);
the rated value(s);
the current in A and the power consumption in VA under worst case conditions.
5. 4. 7
Su ppl y for extern al d evices
If the metering equipm ent provides a suppl y for external devices, e. g. comm unication
modules, then the followi ng information shall be provided:
•
•
•
•
nom inal voltage and operating voltage range;
maxim um load;
kind of and rating of protection, when available, e. g. resettable fuse;
polarity, when relevant.
5. 4. 8
Batteri es
NOTE This subcl ause is based on I EC 60255-27: 201 3, 9. 1 . 8. 1 .
I f the equipment has replaceable batteries and by opening the battery com partment a hazard
appears or if the replacement of the batteries by an incorrect type of battery could result in an
explosion (for exam ple, in the case of certain types of Lithium batteries) then:
•
•
if a user can access the battery, there shall be a marking close to the battery or a
statement in the instruction m anual, user manual and maintenance m anual;
if the battery is elsewhere in the equipm ent, marking is required; this shall be cl ose to the
battery or in a statem ent included in the m aintenance manual.
The m arking or statement shall be similar to the following.
CAUTI ON – Risk of fire if battery is replaced with incorrect type or polarity.
Dispose of used batteries according to instructions.
I t is permissible, where space is lim ited on the equipment to use the warning m ark, see
Table 3 sym bol 1 4 .
The polarity of the battery shall be marked on the equipm ent unless it is not possible to insert
the battery with incorrect polarity.
Conformity is checked by inspection.
5. 4. 9
Sel f-con su mpti on
For the voltage circuits of meters, for stand -alone tariff and load control equipment and for
auxiliary circuits the following inform ation shall be provided in the instruction and m aintenance
manuals:
•
the maxim um power consumption in watts (active power) or volt-amperes (apparent
power), or the m axim um rated input current, with all accessories or plug-in modules
I EC 62052-31 :201 5 © I EC 201 5
– 49 –
connected. I f the equipment can be used on more than one voltage range, separate values
shall be specified for each voltage range unless the maximum and m inim um values do not
differ by m ore than 20 % of the m ean value. The stated value shall not be less than 90 %
of the maxim um value.
For the current circuits of meters:
•
the burden in VA for each current circuit of the metering equipment, measured at the rated
operating current of that circuit.
Conformity is checked by inspection.
5. 4. 1 0
Com m i ss i on i n g
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 5. 4. 6.
Aspects resulting from integration into systems or effects resulting from special ambient or
application conditions may be addressed to the user and/or the installer, if clearl y described in
the instruction manual or in special safety instructions.
NOTE 2 The followin g paragraph is based on I EC 60364-1 : 2005, 1 31 . 7.
I n particular, a statem ent shall be included to the effect that where danger or damage is
expected to arise due to an interruption of supply, suitable provisions shall be made in the
installation or installed equipment.
I f comm issioning tests are necessary to ensure the electrical and thermal safety of metering
equipm ent, inform ation to support these tests shall be provided.
Com missioning information shall include references to hazards that m ight be encountered.
Conformity is checked by inspection of the documentation.
5. 5
5. 5. 1
I n fo rm a t i o n
fo r u s e
G e n e ra l
The user manual shall be written in a language that can be easil y understood by the intended
readership and it shall include all information regarding the safe operation of the metering
equipm ent.
All safety marking shall be clearl y explained. The user m anual shall also indicate an y
hazards, which can result from reasonabl y foreseeable m isuse of the m etering equipm ent.
5. 5. 2
D i s p l a y,
pu sh
b u t t o n s a n d o t h e r c o n t ro l s
The user m anual shall provide a detailed description of all items that can be displayed by the
metering equipment. All push buttons and an y other control devices shall be identified and
their function described.
5. 5. 3
S wi tc h e s
The position (Connected / ON – Disconnected / OFF – Read y for reconnection as applicable)
of an y switch(es) shall be unambiguousl y and clearl y indicated, their operation and an y
related hazards shall be explained in the user m anual.
In particular, there shall be a warning mark adj acent to the switch(es) and an explanation
within the user manual that the open position of the suppl y or load control switch does not
provide isolation from the mains network. Sym bol 1 4 of Table 3 is a suitable marking.
– 50 –
5. 5. 4
I EC 62052-31 :201 5 © I EC 201 5
C o n n e c t i o n t o u s e r’ s e q u i p m e n t
Where it is possible for the user to connect an y equipment to the meter, the necessary
connection diagrams, the identification, marking and description of the connectors as well as
the description of the necessary operations shall be provided.
Where an y hazards exist in the process of connecting an external device, suitable m arking
shall be provided on the m eter.
5. 5. 5
E x t e rn a l p ro t e c t i o n
d evi ces
I f external protection devices such as fuses and circuit breakers may be operated by the user,
then an y safety hazards related to their operation shall be explained in the user manual of the
metering equipment.
5. 5. 6
Cl ean i n g
The instruction, user and m aintenance manuals shall provide information for cleaning,
including the cleaning agents that may be used.
5. 6
I n fo rm a t i o n
fo r m a i n t e n a n c e
NOTE This subcl ause is based on I EC 62477-1 : 201 2, 6. 5. 1
Safety information shall be provided in the maintenance manuals including – as applicable –
the following:
•
•
•
•
•
•
•
•
preventive maintenance procedures and schedules;
safety precautions during maintenance;
location of live parts that can becom e accessible during maintenance (for exam ple, when
covers are rem oved);
adj ustm ent procedures;
sub-assembly and com ponent repair and replacement procedures;
inform ation on safe disposal of the equipm ent and an y replaceable parts;
verification of the safe state of the equipm ent after repair;
an y other relevant information.
These may best be presented as diagram s.
A list of special tools should be provided, when appropriate.
6
6. 1
P ro t e c t i o n a g a i n s t e l e c t ri c a l s h o c k
G e n e ra l
re q u i re m e n t s
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 1 . 1 an d I EC 60255-27: 201 3, 5. 1 .
Metering equipment shall be designed and constructed to ensure personal safety against
electric shock.
Accessible parts (see 6. 2) shall not be hazardous live (see 6. 3). This requirement also applies
to parts that can be accessed after rem oving a cover, opening a door etc. without using a tool.
NOTE 2 Accessibility of parts is to be understood from the point of view of the user. See al so 1 . 1 .
Protection against electric shock shall be m aintained in normal condition, see 6. 4 , and single
fault condition, see 6.5.
I EC 62052-31 :201 5 © I EC 201 5
– 51 –
An y conductive part that is not separated from the hazardous live parts by at least basic
insulation shall be considered to be live part.
A metallic accessible part is considered to be conductive if its surface is bare or is covered by
an insulating layer which does not compl y with the requirements of basic insulation. See
6. 9. 2.
Unearthed accessible conductive parts which m ay become hazardous live under a single fault
condition shall be separated from hazardous live parts by double insulation or reinforced
insulation or be connected to the protective conductor or m eet the requirements of 6. 2 to 6. 6.
Conformity is checked by the determination of accessible parts as specified in 6. 2, and the
measurements of 6. 3 to establish that the levels of 6.3.2 and 6. 3. 3 are not exceeded, followed
by the tests of 6. 4 to 6. 10.
6.2
6.2.1
Determination of accessible parts
General
NOTE 1 Subclause 6. 2 is based on I EC 61 01 0-1 : 201 0, 6. 2. 1 and I EC 60255-27: 201 3 5. 1 . 5. 1 .
NOTE 2 This subclause reproduces I EC 61 01 0-1 : 201 0, 6. 2. 1 (with th e n ote m odified ).
Unless obvious, determination of whether a part is accessible is made as specified below in
6. 2. 2 to 6.2. 4 in all positions of normal use. Test fingers and pins are applied without force
unless a force is specified. Parts are considered to be accessible if they can be touched with
any part of a test finger or test pin.
NOTE 3 Electricity m eterin g equi pm ent in n orm al use do n ot req uire any actions that i ncrease the accessibility of
parts. All service-related acti ons that eventually increase the accessibility of parts (e. g . battery repl acem ent,
calibration, re-seal ing, etc. ) are perform ed by skilled person n el.
Rack-mounted and panel-mounted equipment is installed as specified in the manufacturer's
instructions before making the examinations of 6. 2.2 to 6. 2. 4. For such equipment, the
operator is assumed to be in front of the panel.
6.2.2
Examination
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 2. 2, except that references are m ad e to I EC 61 032: 1 997.
The jointed test finger (test probe B), specified in IEC 61032:1997 is applied in every possible
position. If a part could become accessible by applying a force, the rigid test finger (test probe
11), specified in IEC 61032:1997 is applied with a force of 10 N. The force is exerted by the
tip of the test finger so as to avoid wedge and lever action. The test is applied to all outer
surfaces, including the bottom. However, on equipment accepting plug-in modules the tip of
the jointed test finger is inserted only to a depth of 180 mm from the opening in the
equipment.
The test finger is likewise applied to all openings in the enclosure, including holes. In these
cases, the accessible parts of the enclosure are considered to include any part of the test
finger, which can be inserted into the hole or terminal (see Figure 1).
– 52 –
A
I EC 62052-31 :201 5 © I EC 201 5
B
C
D
E
IEC
Ke y
A
B
C
D
E
I nside of th e eq uipm ent
Outside of th e eq uipm ent
Hazardous live part
Tip of test finger is consid ered to be accessible
Test finger
Fi gu re 1 – M easu rem en ts th rou gh open i n g s in en closu res
6. 2. 3
Open i ng s above parts th at are h azardou s live
NOTE 1 This subcl ause reproduces I EC 61 01 0-1 : 201 0, 6. 2. 3.
A metal test pin 100 mm long and 4 mm in diameter rod is inserted into any openings above
parts which are hazardous live. The test pin is suspended freely and allowed to penetrate up
to 100 mm.
The additional safety measures of 6. 5. 1 for protection in single fault condition are not required
solely because a part is accessible only by this test.
NOTE 2 This exception is perm itted because the i nserti on of an obj ect sim ilar to this test pi n is consid ered to be a
single fault cond ition an d on e m eans of protection is sufficien t.
This test is not applied to terminals.
6. 2. 4
Open in g s for pre-set con trol s
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 2. 4.
A metal test rod of 100 mm long and 3 mm in diameter is inserted through holes intended to
give access to pre-set controls which require the use of a screwdriver or other tool, or to
openings for payment meter physical token acceptors. The test pin is applied in every
possible direction through the hole. Penetration shall not exceed three times the distance
from the enclosure surface to the surface of the control or 100 mm, whichever is smaller.
I EC 62052-31 :201 5 © I EC 201 5
6. 2. 5
– 53 –
Wiri n g termi n al s
NOTE This subcl ause is based on I EC 60255-27: 201 3, 5. 1 . 5. 2. 6.
Wiring terminals covered by a terminal cover, or in a restricted access area and that cannot
be touched in norm al use shall be deemed non-accessible.
Circuits intended to be connected to an external accessible circuit shall be considered as
accessible conductive parts.
Exam ple: Com m unication circu its.
6. 3
6. 3. 1
Li m it valu es for accessi ble parts
G en eral
NOTE This subcl ause is based on I EC 60255-27: 201 3, 5. 1 . 5. 3. 1 .
Voltage between an accessible part and earth or between an y two accessible parts on the
sam e piece of equipment (over a surface or through air), touch current and discharge energ y
shall not exceed the values of 6. 3. 2 in normal condition nor of 6. 3.3 in single fault condition.
6. 3. 2
Levels i n n orm al con di ti on
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 3. 1 .
Voltages above the levels of a) are deemed to be hazardous live if an y of the levels of b) or c)
are exceeded at the same time.
a) the a.c. voltage levels are 33 V r.m .s., 46, 7 V peak and the d.c. voltage level is 70 V. For
equipment intended for use in wet locations, the a.c. voltage levels are 1 6 V r.m .s., 22,6 V
peak and the d.c. voltage level is 35 V.
b) the current levels are:
1 ) 0, 5 mA r.m .s. for sinusoidal waveforms, 0, 7 m A peak for non-sinusoidal waveform or
m ixed frequencies, or 2 mA d.c., when measured with the m easuring circuit of
Figure A. 1 . I f the frequency does not exceed 1 00 H z, the measuring circuit of
Figure A. 2 can be used. The m easuring circuit of Figure A. 4 is used for equipm ent
intended for use in wet locations.
2) 70 mA r.m. s. when measured with the measuring circuit of Figure A. 3. This relates to
possible burns at higher frequencies.
c) the levels of capacitive charge or energ y are:
1 ) 45 µ C charge for voltages up to 1 5 000 V peak or d.c. Line A of Figure 3 shows the
capacitance versus voltage where the charge is 45 µ C.
2) 350 mJ stored energy for voltages above 1 5 000 V peak or d.c.
6. 3. 3
Levels i n si n gl e fau lt con di tion
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 3. 2.
Voltages above the limits of a) are deemed to be hazardous live if an y of the values of b) or c)
are exceeded at the same time.
a) the a.c. voltage levels are 55 V r. m. s., 78 V peak and the d.c. voltage level is 1 40 V d. c.
For equipm ent intended for use in wet locations, the a.c. voltage levels are 33 V r.m .s.,
46, 7 V peak and the d.c. voltage level is 70 V. For voltages of short duration, the duration
versus voltage levels are those of Figure 2, measured across a 50 k Ω resistor;
b) the current levels are:
1 ) 3, 5 m A r. m.s. for sinusoidal waveform s, 5 mA peak for non-sinusoidal waveform s or
m ixed frequencies, or 1 5 m A d. c. , when measured with the m easuring circuit of
– 54 –
I EC 62052-31 :201 5 © I EC 201 5
t
(s)
Figure A. 1 . I f the frequency does not exceed 1 00 H z, the measuring circuit of
Figure A.2 can be used. The m easuring circuit of Figure A. 4 is used for equipment
intended for use in wet locations;
2) 500 mA r. m. s. when m easured with the measuring circuit of Figure A.3. This relates to
possible burns at higher frequencies.
c) the capacitance level is line B of Figure 3.
20
A
10
B
C
D
5
3
2
1
0, 5
0, 3
0, 2
0, 1
0, 05
0, 03
0, 02
0, 01
10
20
30
50
1 00
200 300
500
1 000
U
(V)
IEC
Ke y
A
B
a. c. voltage level in wet locati ons
a. c. voltage level in d ry l ocations
C d. c. voltage l evel in wet locations
D d. c. voltage l evel in dry locations
Fig u re 2 – M axi mu m d u rati on of sh ort-term accessi bl e voltag es
in si n gl e fau lt con d i ti on (see 6. 3. 3 a))
C (F)
I EC 62052-31 :201 5 © I EC 201 5
– 55 –
1 0 −4
7
5
3
2
1 0 −5
7
5
3
2
B
1 0 −6
7
5
3
A
2
1 0 −7
7
5
3
2
1 0 −8
7
5
3
2
1 0 −9
1 02
2
3
5 7 1 03
2
3
5 7 1 04
2
3
5 7 1 05
U (V)
IEC
Key
A
B
V
C
Norm al con dition
Single fault con dition
Voltage
Capacitance
Figure 3 – Capacitance level versus voltage in normal condition and
single fault condition (see 6.3.2 c) and 6.3.3 c))
– 56 –
6. 4
P ri m a ry m e a n s o f p ro t e c t i o n
6. 4. 1
( p ro t e c t i o n
I EC 62052-31 :201 5 © I EC 201 5
a g a i n s t d i re c t c o n t a c t )
G e n e ra l
NOTE 1 Su bclause 6. 4 is based on I EC 61 01 0-1 : 201 0, 6. 4 (Prim ary m eans of protecti on) and on I EC 6025527: 201 3, 5. 1 . 2.
NOTE 2 The foll owi ng reproduces I EC 61 01 0-1 : 201 0, 6. 4. 1 , except that th e term “case” is used instead of
enclosu res an d protecti ve barri ers.
Accessible parts shall be prevented from becom ing hazardous live by one or m ore of the
following m eans:
a) the equipment case, see 6. 4. 2;
b) basic insulation, see 6. 4. 3; or
c) im pedance, see 6.4. 4.
Co n form ity is ch e cke d b y in s p e ctio n a n d a s sp e cifie d in 6. 4. 2 to 6. 4. 4 .
6. 4. 2
E q u i p m en t ca s e
NOTE This subcl ause is based on I EC 62052-1 1 : 2003, an d I EC 61 01 0-1 : 201 0, 6. 4. 2.
The case of metering equipment shall prevent access to hazardous live parts, such that they
are not accessible in normal use. For constructional requirem ents, see 6. 9. 4.
I f the case provides protection by insulation, then it shall meet the requirem ents of at least
basic insulation.
I f enclosures or protective barriers provide protection by limiting access, clearances and
creepage distances between accessible parts and hazardous li ve parts shall meet the
requirem ents of 6.7 and the applicable requirem ents for basic insulation.
Co n form ity is ch e cke d a s sp e cifie d in 6. 7 a n d 8. 2.
6. 4. 3
Basi c i n s u l ati on
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 4. 3.
Clearances , creepage distances and solid insulation forming basic insulation between
accessible parts and hazardous live parts shall meet the requirements of 6.7.
Co n form ity is ch e cke d a s sp e cifie d in 6. 7.
6 . 4. 4
I m p ed an ce
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 4. 4.
An impedance used for basic protection shall m eet all the following requirements:
a) it shall lim it the current or voltage to not more than the applicable level of 6. 3. 3;
b) it shall be rated for the m axim um working voltage and for the amount of power that it will
dissipate;
c) clearance and creepage distance between term inations of impedances shall meet the
applicable requirem ents of 6. 7 for basic insulation.
Co n fo rm ity is ch e cke d b y in sp e ctio n , b y m e a s urin g th e volta ge or curre n t to c on firm th a t th e y
do
n o t e xce e d th e
sp e cifie d in 6. 7.
le ve ls
of 6. 3. 3
and
b y m e a surin g
cle a ra n ce
a n d cre e p a ge
dis ta n ce
as
I EC 62052-31 :201 5 © I EC 201 5
– 57 –
Addi tion al mean s of protecti on in case of sin g le fau lt con d ition s (protection
ag ain st i n di rect con tact)
6. 5
6. 5. 1
G en eral
NOTE 1 Fault protection gen erally correspon ds to protection agai nst indirect contact, m ainly with regard to failu re
of basic insulati on.
NOTE 2 This subclause reproduces – m utatis m utandis – I EC 61 01 0-1 : 201 0, 6. 5. 1 .
Accessible parts shall be prevented from becoming hazardous live in single fault condition.
The primary m eans of protection (see 6. 4) shall be supplemented by one of a), b) c) or d).
Alternatively one of the single m eans of protection e) or f) shall be used. See Figure 4.
a)
b)
c)
d)
e)
f)
protective bonding (see 6. 5.2);
supplem entary insulation (see 6. 5.3);
automatic disconnection of the suppl y (see 6. 5.5);
current- or voltage limiting device (see 6.5. 6);
reinforced insulation (see 6.5. 3);
protective impedance (see 6. 5. 4).
Conformity is checked as specified in 6. 5. 2 to 6. 5. 6.
IEC
Fig u re 4 – Acceptable arran gemen ts of protecti on m ean s ag ai n st el ectri c sh ock
6. 5. 2
6. 5. 2.1
Protecti ve bon d in g
Gen eral
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 5. 2. 1 an d I EC 60255-27: 201 3, 5. 1 . 6. 2.
Accessible conductive parts shall be bonded to the protective conductor term inal if they could
becom e hazardous live in case of a single fault of the prim ary m eans of protection specified in
6. 4. Alternativel y, accessible conductive parts shall be separated from parts, which are
hazardous live , by a conductive protective screen bonded to the protective conductor terminal .
– 58 –
I EC 62052-31 :201 5 © I EC 201 5
Unearthed accessible conductive parts such as nameplates, screws, suspensions and rivets
need not be bonded to the protective conductor terminal if they are separated from all
hazardous live parts by d ouble insulation or reinforced insulation.
Conformity is checked as specified in 6. 5. 2. 2 to 6. 5. 2. 5.
6. 5. 2 . 2
I n t e g ri t y o f p ro t e c t i v e b o n d i n g
NOTE 1 This subcl ause reproduces I EC 61 01 0-1 : 201 0, 6. 5. 2. 2.
The integrity of protective bonding shall be assured as specified below:
a) protective bonding shall consist of directl y connected structural parts or discrete
conductors, or both. I t shall withstand all thermal and d ynamic stresses to which it could
be subjected before the over-current protective means specified in 0 disconnects the
equipm ent from the supply;
b) soldered connections subj ect to mechanical stress shall be mechanicall y secured
independentl y from the soldering. Such connections shall not be used for other purposes
such as fixing constructional parts;
c) screw connections shall be secured against loosening;
d) if a part of the equipm ent is rem ovable, the protective bonding for the remainder of the
equipm ent shall not be interrupted (except for a part that also carries the mains input
connection to the whole equipm ent);
e) unless they are specifically designed for electrical inter-connection and meet the
requirements of 6. 5.2.4, m ovable conductive connections, for exam ple, hinges, slides,
etc., shall not be the sole protective bonding path;
f) the exterior m etal braid of cables shall not be regarded as protective bonding, even if
connected to the protective conductor term inal;
g) if power from the mains supply is passed through m etering equipment of protective class I
for use by other equipm ent, means shall also be provided for passing the protective
conductor through the metering equipm ent to protect the other equipment. The impedance
of the protective conductor path through the equipm ent shall not exceed the values
specified in 6. 5.2. 4.
However, if metering equipment is of protective class I I , then an y – auxiliary – equipm ent
powered through this equipment shall be also of protective class I I .
NOTE 2 I tem g) concerns onl y au xili ary equi pm ent to the m eteri ng equi pm ent.
h) protective conductors may be bare or insulated. I nsulation shall be green-and-yellow,
except in the following cases:
1 ) for earthing braids, either green-and-yellow or colourless-transparent;
2) for internal protective conductors, and other conductors connected to the protective
conductor terminal in assem blies such as ribbon cables, busbars, flexible printed
wiring, etc. , an y colour may be used provided that no hazard is likel y to arise from nonidentification of the protective conductor.
Equipment using protective bonding shall be provided with a terminal that is suitable for
connection to a protective conductor and m eets the requirem ents of 6. 5. 2. 3.
Conformity is checked by inspection.
6. 5. 2 . 3
P ro t e c t i v e c o n d u c t o r t e rm i n a l
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 5. 2. 3 ad apted for m etering.
The protective conductor terminal shall meet the following requirem ents:
I EC 62052-31 :201 5 © I EC 201 5
– 59 –
a) the contact surfaces shall be m etal. Materials of protective bonding system s shall be
chosen to minimize electro-chemical corrosion between the term inal and the protective
conductor, or an y other m etal in contact with them ;
b) the protective conductor term inal should, if possible, form part of the meter base;
c) the protective conductor terminal should preferabl y be located adjacent to the term inal
block intended for connecting the m ains-circuits;
d) in the case of direct connected meters, the current carrying capacity of the protective
conductor term inal shall be at least equivalent to the maximum current specified;
e) in the case of transformer connected m eters, the current carrying capacity of the
protective conductor terminal shall be at least equivalent to 2 tim es the m axim um current
specified, or the current carrying capacity of the m ains voltage term inals, whichever is
larger;
f) in the case of stand-alone tim e switches and ripple control receivers, the current carrying
capacity of the protective conductor term inal shall be at least equivalent to the maxim um
total current specified;
g) plug-in type protective conductor term inals combined with other terminals and intended to
be connected and disconnected without the use of a tool, shall be designed so that the
protective conductor connection m akes first and breaks last with respect to the other
connections;
h) after installation, it shall not be possible to loosen the protective earth terminal without the
use of a tool;
i) if the protective conductor term inal is also used for other bonding purposes, the protective
conductor shall be applied first and secured independently of other connections. The
protective conductor shall be connected in such a way that it is unlikel y to be removed
during servicing that does not require disconnection of the protective conductor;
j) it shall be clearl y identified by the graphical sym bol 6 of Table 3;
k) functional earth term inals (for example, measuring earth terminals) shall allow a
connection which is independent from the connection of the protective conductor;
Equipment m ay be equipped with functional earth terminals, irrespective of the protective
means taken.
l) if the protective conductor terminal is a binding screw assem bl y (see Figure 5), it shall be
of a suitable size for the bond wire, but with a thread size no smaller than 4, 0 mm , with at
least three turns of the screw engaged;
m) the contact pressure required for a bonding connection shall not be capable of being
reduced by deform ation of m aterials form ing part of the connection.
D
B
C
D
A
A
IEC
Key:
A
B
C
D
fi xed part
washer or clam ping pl ate
anti-spread d evice
conductor space
Figure 5 – Examples of binding screw assemblies
– 60 –
I EC 62052-31 :201 5 © I EC 201 5
Co n form ity is ch e cke d b y in s p e ctio n . Co n form ity for l) is a lso ch e cke d b y th e fo llo win g te st:
Th e b in din g scre w a ss e m b ly is to b e tigh te n e d a n d lo ose n e d th re e tim e s,
to ge th e r with th e
le a s t fa vo ura b le co n ductor to b e se cure d, us in g th e tigh te n in g torque s sp e cifie d in Ta b le 4 . A ll
p a rts o f th e b in din g scre w a sse m b ly s h a ll with s ta n d th is te st with o ut m e ch a n ica l fa ilure .
Tabl e 4 – Ti g h ten i n g
Th re a d
s i ze,
Ti g h te n i n g
6. 5. 2 . 4
t o rq u e fo r b i n d i n g
mm
t o rq u e ,
Nm
s c re w a s s e m b l i e s
4, 0
5, 0
6, 0
8, 0
1 0, 0
1 ,2
2, 0
3, 0
6, 0
1 0, 0
I m p e d a n c e o f p ro t e c t i v e b o n d i n g
o f p e rm a n e n t l y c o n n e c t e d
eq u i pm en t
NOTE 1 The followin g text is based on I EC 61 01 0-1 : 201 0, 6. 5. 2. 5 adapted for m eterin g.
NOTE 2 M eterin g eq uipm ent within the scope of this stand ard are al ways perm an entl y conn ected.
Protective bonding of permanentl y connected equipment shall be of low impedance.
Co n form ity is ch e cke d b y a p p lyin g a te st curre n t for 1
te rm in a l a n d e a ch
a cce ssib le
co n ductive
m in b e twe e n th e p rote ctive con ductor
p a rt for wh ich
p rote ctive
b o n din g is re quire d.
Th e
vo lta ge b e twe e n th e m sh a ll n o t e xce e d 1 0 V a . c. r. m . s. or d. c .
a)
in
th e
ca se
o f dire ct
con n e cte d
m e te rs,
th e
te st
curre n t
sh a ll
be
e qua l
to
twice
th e
(e xce p t
th e
m a xim um curre n t of th e m e te r. Howe ve r, if th e e quip m e n t
•
con ta in s
n e utra l)
ove rcurre n t
p ro te ctio n
o r is sp e cifie d b y th e
de vice s
fo r a ll
m a n ufa cture r to
h a za rdo us
be
live
te rm in a ls
in sta lle d with
e xte rn a l ove rcurre n t
p ro te ction de vice s fo r a ll h a za rdous live te rm in a ls (e xce p t th e n e utra l) ;
•
a n d th e wirin g o n th e sup p ly s ide of th e o ve rcurre n t p ro te ction de vice s ca n n o t b e co m e
con n e cte d to a cce ss ib le con ductive p a rts in ca s e of a s in gle fa ult,
th e te st curre n t n e e d n o t b e m ore th a n twice th e h igh e st ra te d curre n t o f th e ove rcurre n t
p ro te ction de vice s.
b)
in th e ca s e o f curre n t tra n sfo rm e r o r vo lta ge a n d curre n t tra n s fo rm e r o p e ra te d m e te rs, th e
te s t curre n t sh a ll b e th e gre a te r o f:
•
th e va lue e q ua l to twice th e n o m in a l curre n t o f th e ove rcurre n t p rote ctio n in th e vo lta ge
circuit(s) o r o th e r h a za rdous live circuits a s re co m m e n de d b y th e m a n ufa cture r; or
•
c)
in
25 A ;
th e
ca se
of ta riff a n d
lo a d
co n tro l th e
te st curre n t sh a ll b e
e q ua l to
twice
th e
tota l
curre n t.
6. 5. 2 . 5
T ra n s fo rm e r p ro t e c t i v e b o n d i n g s c re e n
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 5. 2. 6.
I f a transformer is fitted with a screen for protective bonding purposes that is separated onl y
by basic insulation from a winding that is connected to a hazardous live circuit, the screen
shall satisfy the requirements of 6. 5. 2.2 a) and b), and be of low im pedance.
Co n form ity is ch e cke d b y in s p e ctio n a n d th e follo win g te sts :
•
a
te st
curre n t
s p e cifie d
in
6. 5. 2. 4
is
a p p lie d
for
1
m in
b e twe e n
th e
scre e n
and
th e
p ro te ctive co n ductor te rm in a l. Th e vo lta ge b e twe e n th e m sh a ll n o t e xce e d 1 0 V a . c. r. m . s .
or d. c.
NOTE 2 A speciall y prepared sam ple transform er havin g an extra lead -out wi re from the free end of th e screen is
used to ensure that the current duri ng th e test passes throug h the screen.
I EC 62052-31 :201 5 © I EC 201 5
6. 5. 3
– 61 –
Su ppl em en tary in su l ati on an d rein forced i n su l ati on
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 5. 3.
Clearances, creepage distances and solid insulation forming supplem entary insulation or
reinforced insulation shall meet the applicable requirements of 6. 7.
Co n form ity is ch e cke d a s sp e cifie d in 6. 7.
6. 5. 4
Protective i mped an ce
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 5. 4.
A protective impedance shall limit the current or voltage to the levels of 6. 3.2 in norm al
condition and 6.3. 3 in single fault condition.
I nsulation between the terminations of the protective impedance shall m eet the requirem ents
of 6. 7 for double insulation or reinforced insulation.
A protective impedance may be one or more of the following:
a) an appropriate single com ponent which shall be constructed selected and tested so that
safety and reliability for protection against electric shock is assured. I n particular, the
com ponent shall be:
1 ) rated for twice the m aximum working voltage;
2) if a resistor, rated for twi ce the power dissipation for the maximum working voltage.
b) a com bination of com ponents.
A protective im pedance shall not be a single electronic device that employs electron
conduction in a vacuum , gas or semiconductor.
Co n form ity is ch e cke d b y in sp e ctio n , b y m e a surin g th e curre n t o r vo lta ge to con firm th a t th e y
do n o t e xce e d th e a p p lica b le le ve ls o f 6. 3 a n d b y m e a surin g cle a ra n ce a n d cre e p a ge dis ta n ce
a s sp e cifie d in 6. 7. Con form ity o f a s in gle co m p o n e n t is a dditio n a lly ch e cke d b y in s p e ctio n o f
its ra tin gs .
6. 5. 5
Au tomatic d iscon n ection of th e su ppl y
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 5. 5.
NOTE 2 Autom atic disconnection discussed in this subclause concerns an y autom ati c device bui lt in the
equi pm ent to clear faults. Such devices are generall y n ot used in m eterin g eq uipm ent.
NOTE 3 Th ey are not be confused with th e su ppl y control switches th at m ay be controll ed locall y or rem otel y to
support applications like conn ection / disconnecti on of the suppl y, load lim itation, paym ent m etering, etc. Such
suppl y control switches g en erally do not provide overcurrent protection; if they have su ch function, then that
function is outside th e scope of this standard.
An autom atic disconnection device shall m eet both the following requirem ents:
a) it shall be rated to disconnect the load within the tim e specified in Figure 2;
b) it shall be rated for the maximum rated load conditions of the equipment.
Co n form ity is ch e cke d b y in s p e ctio n of th e de vice sp e cifica tio n . In ca s e o f do ub t, th e de vice is
te ste d to ch e ck th a t it dis con n e cts th e sup p ly with in th e re q uire d tim e .
– 62 –
6.5.6
I EC 62052-31 :201 5 © I EC 201 5
Current- or voltage-limiting device
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 5. 6.
I f a current- or voltage-limiting device is used for protection in single fault condition, it shall
m eet all the following requirements:
a) it shall be rated to lim it the current or voltage as specified in 6. 3.3;
b) it shall be rated for the maximum working voltage and, if applicable, for the m axim um
operational current;
c) clearance and creepage distance between the term inations of the current or voltage
lim iting device shall meet the applicable requirem ent of 6. 7 for supplementary insulation .
Co n form ity is ch e cke d b y in sp e ctio n , b y m e a s urin g th e volta ge or curre n t to con firm th a t th ey
do
n o t e xce e d th e
le ve ls
o f 6. 3. 3,
a n d b y m e a s urin g
cle a ra n ce
a n d cre e p a ge
dis ta n ce
as
sp e cifie d in 6. 7.
6.6
Connection to external circuits
6.6.1
General
NOTE 1 Subclause 6. 6 is based on I EC 61 01 0-1 : 201 0, 6. 6.
I n normal condition and in single fault condition, no accessible parts of the equipment and no
accessible parts of an external circuit shall becom e hazardous live as a result of connecting
the external circuit to the equipment.
NOTE 2 Extern al circuits are all circuits conn ected to term inal s of the equi pm ent.
The suppl y and load side terminals of the m eter and their external circuits are not considered
to be accessible parts. Likewise, the terminals of the load switches and their external circuits
are not considered to be accessible parts.
Protection shall be achieved by separation of circuits, unless short-circuiting of the separation
could not cause a hazard.
As specified in 5. 4. 4, the m anufacturer's instructions or equipment m arkings shall include the
following inform ation, if applicable, for each external terminal:
a) rated conditions at which the terminal has been designed to operate while maintaining
safety (maximum rated input/output voltage, specific type of connector, designated use,
etc.);
b) rating of the insulation required for the external circuit to conform to the requirements for
protection against electric shock, arising from the connection to the term inal, in normal
condition and single fault condition.
NOTE 3 The type an d rati ng of extern al circuits con nected to the m eter are g enerall y un der local reg ul ati ons.
Co n form ity is ch e cke d b y:
1)
in sp e ctio n ;
2)
th e de te rm in a tio n s of 6. 2;
3)
th e m e a s ure m e n ts of 6. 3 a n d 6. 7;
4)
th e
die le ctric te s ts of 6. 1 0. 4 (with o ut h um idity p re co n dition in g)
in sula tio n (s e e 6. 7) .
a p p lica b le to th e
typ e
of
I EC 62052-31 :201 5 © I EC 201 5
6. 6. 2
T e rm i n a l s fo r e xt e rn a l
– 63 –
c i rc u i t s
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 6. 2.
Conductive parts of term inals that are accessible to the user and that receive a charge from
an internal capacitor shall not be hazardous live 1 0 s after rem oving power from the m etering
equipm ent.
Co n form ity is ch e cke d b y in sp e ctio n , a n d b y th e de te rm in a tio n of a cce ss ib le con ductive p a rts
a s sp e cifie d in 6. 2 a n d in ca se o f do ub t b y m e a s ure m e n t o f th e re m a in in g vo lta ge o r ch a rge .
6. 6. 3
T e rm i n a l s fo r s t ra n d e d
c o n d u c t o rs
See 6. 9. 7.
6. 7
I n s u l ati o n
6. 7. 1
6. 7. 1 . 1
G e n e ra l
re q u i re m e n t s
– E l e c t ri c a l
s t re s s e s ,
o v e rv o l t a g e s a n d o v e rv o l t a g e c a t e g o ri e s
E l e c t ri c s t re s s e s o ri g i n a t i n g fro m
m ai n s
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 7. 1 . 1 an d I EC 60364-4-44: 2007, adapted to m etering.
Electric stresses originating from mains include:
a) working voltage across the insulation. This working voltage is normall y the line-to-neutral
voltage of the m ains suppl y. I n the case of pol yphase metering equipm ent some
insulations will be stressed by the line-to-line voltage;
NOTE 2 An exam ple for the latter is the term inal block of polyphase m eters, where lin e-to-line voltag e is
present between term inals of the different ph ases .
b) transient overvoltages that m ay occasionall y appear on the line conductors. The
m agnitude of the overvoltages depends on the overvoltage category and the line-toneutral voltage of the mains suppl y;
c) temporary power frequency overvoltages.
6. 7. 1 . 2
P ro t e c t i o n
a g a i n s t o v e rv o l t a g e s o f a t m o s p h e ri c o ri g i n o r d u e t o s w i t c h i n g
NOTE This subcl ause is based on I EC 60364-4-44: 2007, 443. 1 .
Metering equipment shall be protected against transient overvoltages of atm ospheric origin
transmitted by the suppl y distribution system and against switching overvoltages.
I n general, switching overvoltages are lower than overvoltages of atmospheric origin and
therefore the requirem ents regarding protection against overvoltages of atm ospheric origin
norm all y cover protection against switching overvoltages.
6. 7. 1 . 3
C l a s s i fi c a t i o n o f i m p u l s e w i t h s t a n d
v o l t a g e s ( o v e rv o l t a g e c a t e g o ri e s )
The im pulse withstand voltage (overvoltage category, OVC) is used to classify equipm ent
energized directl y from the mains.
I EC 60364-4-44: 2007, 443. 2. 2 specifies overvoltage categories I to I V.
For m etering equipment, overvoltage category I I I is taken as a basis for determining
clearances. See also 1 . 4 and Annex K.
NOTE Accordin g to I EC 60664-1 : 2007, 4. 3. 3. 2. 2, equi pm ent of overvoltage category I I I is equipm ent in fi xed
installati ons and for cases where the reliability and the avail abil ity of the eq uipm ent are subj ect to special
requirem ents.
– 64 –
6.7.2
6.7.2.1
I EC 62052-31 :201 5 © I EC 201 5
The nature of insulation
General
NOTE Subclause 6. 7. 2 is based on I EC 61 01 0-1 : 201 0, 6. 7. 1 . 1 .
I nsulation between circuits and accessible parts (see 6. 2) or between separate circuits
consists of a combination of clearances, creepage distances and solid insulation. When used
to provide protection against a hazard, the insulation needs to withstand the electric stresses
that are caused by the voltages that m ay appear on the m ains or in the equipment.
The requirem ents for insulation depend on:
a) the required level of insulation (basic insulation, supplementary insulation, or reinforced
insulation);
b) the maximum transient overvoltage that may appear on the circuit, either as a result of an
external event (such as a lightning strike or a switching transient), or as the result of the
operation of the equipm ent;
c) the m axim um working voltage (including stead y-state and recurring peak voltages);
d) the pollution degree of the micro-environm ent;
e) the maxim um temporary overvoltage that m ay occur in a mains-circuit because of a fault
in the mains distribution system . See also 6.1 0. 3. 2.
6.7.2.2
Clearances
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 7. 1 . 2, except that for the m easurem ent of clearances the
text refers to I EC 60664-1 : 2007 , 6. 2.
Required clearances depend on the factors in 6. 7.1 .1 a) to c) as well as the rated altitude. I f
the equipment is rated to operate at an altitude greater than 2 000 m, then the clearances
specified in the Tables referenced from the overview Table 6 shall be m ultiplied by the factors
of Table 5.
Table 5 – Multiplication factors for clearance for altitudes up to 5 000 m
Rated operating alti tude
Multiplication factor
Up to 2 000
1 , 00
2 001 to 3 000
1 ,1 4
3 001 to 4 000
1 , 29
4 001 to 5 000
1 , 48
m
NOTE 1 Th e val ues are taken from I EC 61 01 0-1 : 201 0, Tabl e 3. See also
I EC 60664-1 : 2007, Tabl e A. 2.
NOTE 2 See also 6. 1 0. 2. 7, Table 24.
For m easurement of clearances, see I EC 60664-1 :2007 , 6. 2.
6.7.2.3
Creepage distances
NOTE This subclause reproduces I EC 61 01 0-1 : 201 0, 6. 7. 1 . 3, except that for the m easurem ent of creepage
distances it refers to IEC 60664-1 :2007, 6. 2.
Required creepage distances depend on the factors in 6. 7. 1 .1 a) to c) as well the
Comparative Tracking I ndex (CTI ) of the insulating m aterial.
Materials are separated into four groups according to their CTI values, as follows:
I EC 62052-31 :201 5 © I EC 201 5
•
•
•
•
m aterial
m aterial
m aterial
m aterial
group
group
group
group
– 65 –
I : 600 < CTI ;
I I : 400 < CTI < 600;
I I I a: 1 75 < CTI < 400;
I I I b: 1 00 < CTI < 1 75.
These CTI values refer to values obtained, in accordance with I EC 601 1 2, on sam ples of the
relevant m aterial specifically made for the purpose and tested with solution A. For m aterials
where the CTI value is not known, material group I I I b is assum ed.
For glass, ceram ics, or other inorganic insulating materials which do not track, there are no
requirements for creepage distances .
For m easurement of creepage distances, see I EC 60664-1 :2007, 6. 2.
6. 7. 2. 4
Solid i n su l ation
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 7. 1 . 4.
The requirem ents for solid insulation depend on factors in 6. 7. 1 . 1 a) to c).
The term “solid insulation” is used to describe m an y different types of constructions, including
monolithic blocks of insulating material, and insulation subsystem s com posed of multiple
insulating materials, organized in layers or otherwise.
The electric strength of a thickness of solid insulation is considerabl y greater than that of the
sam e thickness of air. The insulating distances through solid insulation are therefore typicall y
smaller than the distances through air. As a result, electric fields in solid insulation are
typically higher, and often are less homogeneous.
Solid insulation material may contain gaps or voids. When a solid insulation system is
constructed from layers of solid m aterials, there are also likel y to be gaps or voids between
the layers. These voids will perturb the electric field so that a disproportionatel y large part of
the electric field is located in the void, potentiall y causing ionisation within the void, resulting
in partial discharge. These partial discharges will influence the adjacent solid insulation and
m ay reduce its service life.
Solid insulation is not a renewable m edium : damage is cum ulative over the life of the
equipment. Solid insulation is also subj ect to ageing and to degradation from repeated high
voltage testing.
6. 7. 2. 5
Req u i rem en ts for i n su l ation accordin g to type of ci rcu it
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 6. 7. 1 . 5 an d Annex K.
Requirements for insulation in particular circuits are specified as follows:
a) in 0 for m ains-circuits;
b) in 6. 7. 4 for non - m ains-circuits;
c) in 6. 7. 5 for circuits that have one or more of the followi ng characteristics:
1 ) the maxim um possible transient overvoltage is lim ited by the suppl y source or
the equipment (see 6. 7. 6) to a known level below the level assum ed for the
circuit;
2) the maximum possible transient overvoltage is above the level assumed for the
circuit;
3) the working voltage is the sum of voltages from m ore than one circuit, or is a
voltage;
within
m ains
mains
m ixed
– 66 –
I EC 62052-31 :201 5 © I EC 201 5
4) the working voltage includes a recurring peak voltage that may include a periodic nonsinusoidal waveform or a non-periodic waveform that occurs with som e regularity
5) the working voltage has a frequency above 30 kHz.
Table 6 provides an overview of the clauses specifying the requirem ents and the tests for
insulations. Where no voltage test is specified, conform ity is verified by inspection and / or
measurement of m echanical dim ensions.
I EC 62052-31 :201 5 © I EC 201 5
– 67 –
T a b l e 6 – O v e rv i e w o f c l a u s e s s p e c i fy i n g
re q u i re m e n t s a n d
Re q u i re m e n t s
t e s t s fo r i n s u l a t i o n s
Te s t c l a u s e s
T yp e o f
i n s u l a ti o n
Cl au s e
Ta b l e /
I m pu l se
F i g u re
vo l ta g e
5 s
a. c.
vo l tag e
1
a. c.
min
vo l t a g e
1
d . c.
min
vo l ta g e
M a i n s c i rc u i t s
Clearance
6. 7. 3. 1
0
6. 7. 3. 3
Creepage
Solid
insulati on
Mould ed and
potted parts
PWBs inner
insulati ng
layers
6. 7. 3. 4. 2
Thin film
insulati on
6. 7. 3. 4. 4
6. 7. 3. 4. 1
6. 7. 3. 4. 3
Table 7
Table 8
Table 9
Table 1 0
Table 1 1
Figu re 6
Table 1 2
Figu re 7
Table 1 0
Table 1 2
Figu re 8
Table 8
Table 9
Table 1 0
Table 1 2
–
–
6. 1 0. 4. 4. 2. 2
(3 cycles)
–
–
6. 1 0. 4. 4. 2. 3
(2 x3 x1 0 m s)
–
6. 1 0. 4. 4. 4. 2
6. 1 0. 4. 4. 4. 3 a)
6. 1 0. 4. 4. 4. 4 a)
–
–
–
–
–
–
–
–
–
–
–
6. 1 0. 4. 4. 4. 4 b)
–
6. 1 0. 4. 4. 2. 1
N o n -m a i n s
Clearance
Creepage
Solid
insulati on
Mould ed and
potted parts
PWBs inner
insulati ng
layers
Thin film
insulati on
c i rc u i t s
6. 7. 4. 2
6. 7. 4. 3
Table 1 3
Table 1 4
–
–
6. 1 0. 4. 4. 3
–
–
–
6. 1 0. 4. 4. 3
–
6. 7. 4. 4. 1
Table 1 3
–
6. 1 0. 4. 4. 4. 3 b)
6. 1 0. 4. 4. 4. 4 c)
–
6. 7. 4. 4. 2
Figu re 6
Table 1 5
Figu re 7
Table 1 3
Table 1 5
Figu re 8
Table 1 3
Table 1 4
Table 1 5
–
–
–
–
–
–
–
–
–
–
6. 1 0. 4. 4. 4. 4 d )
6. 1 0. 4. 4. 4. 5
0
6. 7. 4. 4. 4
C i rc u i t s w i t h
s p e ci al
o v e rv o l t a g e s
Clearance
6. 7. 5. 2
Table 1 6
Table 1 7
6. 1 0. 4. 4. 5
6. 1 0. 4. 4. 5
–
–
Creepage
0
(6. 7. 4. 3)
Table 1 4
–
–
–
–
Solid
insulati on
6. 7. 5. 5
Table 1 7
–
–
–
–
Clearance
6. 7. 5. 3
0
(6. 7. 4. 3)
6. 7. 5. 5
(6. 7. 4. 4)
Table 1 8
–
–
–
–
Table 1 4
–
–
–
–
Table 1 7
–
–
–
–
C i rc u i t s w i t h
Creepage
Solid
insulati on
re c u rri n g
p e a k vo l ta g e
C i rc u i t s a b o v e 3 0 k H z
Clearance
Creepage
Solid
insulati on
6. 7. 5. 3
0
(6. 7. 4. 3)
6. 7. 5. 5
(6. 7. 4. 4)
Table 1 8
–
–
–
–
Table 1 4
–
–
–
–
Table 1 7
–
–
–
–
– 68 –
6. 7. 3
I n s u l ati o n
6. 7. 3. 1
I EC 62052-31 :201 5 © I EC 201 5
re q u i re m e n t s fo r m a i n s - c i rc u i t s
N om i n al
vo l tag es an d
ra t e d
i m p u l s e vo l tag e s
The rated im pulse voltage of the equipment shall be selected from Table 7 corresponding to
the nominal/rated voltage of the equipm ent and the required level of insulation.
Tabl e 7 – N om i n al
N om i n al
/ ra t e d v o l t a g e s a n d
v o l t a g e o f t h e s u p p l y s ys t e m ,
V
ra t e d
i m p u l s e vo l tag e s
a
Ra t e d
i m p u l s e vo l ta g e ,
Vo l ta g e
V
b
l i n e to
Th re e -
n e u tra l
T h re e ph ase
ph ase
fo u r- w i re
t h re e - w i re
ph ase
n ot
t w o - w i re
wi th
d e ri v e d
ph ase
fro m
su ppl e-
Re i n fo rc e d
t h re e -
n om i n al
m e n ta ry
i n s u l a ti o n
w i re
e a rth e d
Ra ti o n a l i z e d
Si n g l eSi n g l e-
e a rth e d
vo l ta g e
vo l ta g e s
c
d
Basi c an d
i n s u l a ti o n
n e u tra l
57, 7/1 00
63, 5/1 1 0
66, 5/1 1 5
66, 5
1 00
1 00
1 500
2 500
1 50
1 60
2 500
4 000
300
320
4 000
6 000
600
630
6 000
8 000
69/1 20
1 20/208
1 1 5, 1 20
1 27/220
1 27
1 00
1 1 0, 1 20,
1 27
1 00-200
1 20-240
200, 220,
220/380
230, 240
230/400
260, 277,
230
220-440
240/41 5
347, 380,
240
230-460
277/480
400, 41 5,
480
480-960
440, 480
347/600
380/660
400/690
500, 577,
600
a
I n som e countries, oth er val ues m ay be i n use.
b
I nsulation coordi nati on uses a preferred series of val ues of rated im pulse voltage: 330 V, 500 V, 800 V, 1
500 V, 2 500 V, 4 000 V, 6 000 V, 8 000 V, 1 2 000 V. The valu es specified i n this table correspon d to
overvoltage categ ory I I I . For reinforced insul ati on, th e valu es are on e step high er in th e preferred seri es than
what is specified for basic insu lation. See IEC 60664-1 :2007, 5. 1 . 6.
c
For d eterm inin g clearances an d solid insul ation in m ains circuits. See IEC 60664-1 :2007, Table B. 1 an d Tabl e
F. 1 .
d
For d eterm inin g creepage distances for basic and supplem entary insul ation in m ains circuits. See IEC 606641 :2007, Clauses F. 3a, F. 3b and F. 4.
Exam ple: For a three-ph ase four-wi re m eter with rated voltag e of 230/400 V the voltage l ine-to-n eutral deri ved
from nom inal voltages is 300 V. The rated im pulse voltage for testing clearances for basic insulati on is 4 000 V
and for reinforced insul ation 6 000 V.
The rati on ali zed voltage for insulation lin e-to-li ne for all system s used to determ ine creepag e distances for basic
and su ppl em entary insul ation i s 320 V.
I EC 62052-31 :201 5 © I EC 201 5
6.7.3.2
– 69 –
Clearances for mains-circuits
Clearances for mains-circuits shall m eet the values of Table 8. I f the equipment is rated to
operate at an altitude greater than 2 000 m, the clearance shall be multiplied by the factors of
Table 5.
Table 8 – Clearances for mains-circuits
Minimum clearances in air up to 2 000 m above sea level
Pollution degree
Rated impulse vol tage
(from Table 7)
Basi c and
supplementary
insulation
Reinforced
insulation
1
V
2
(indoor meter)
3
(outdoor meter)
mm
1 500
–
0, 5
0, 5
0, 8
2 500
2 500
1 ,5
1 ,5
1 ,5
4 000
4 000
3, 0
3, 0
3, 0
6 000
6 000
5, 5
5, 5
5, 5
–
8 000
8, 0
8, 0
8, 0
NOTE 1 The val ues h ave been taken from IEC 60664-1 :2007, Table F. 2, for Case A, inh om ogeneous field.
NOTE 2 For i nd oor m eters pollution degree 2, for outdoor m eters polluti on d eg ree 3 has been assum ed.
NOTE 3 Poll ution degree 1 applies if poll ution is redu ced by coati ng, pottin g or m oulding. For m ore
inform ation, see IEC 60664-3:2003.
The pu rchaser m ay specify hi gher rated im pulse voltag e th en th e val ue specified i n Tabl e 7. I n this case, th e
val ues specifi ed sh oul d be used. For rated im pulse voltages above 8 000 V the requi red clearances can be
foun d in IEC 60664-1 :2007, Tabl e F. 2.
Conformity is checked by inspection, measurement and the test specified in 6. 1 0. 4. 4. 2.
6.7.3.3
Creepage distances for mains-circuits
Creepage distances for m ains-circuits for basic insulation and supplem entary insulation shall
m eet the values of Table 9.
Creepage distances of double insulation are the sum of the values of the basic insulation and
supplem entary insulation, which com pose the double insulation system. Creepage distances
for reinforced insulation shall be twice those determ ined for basic insulation from Table 9.
– 70 –
I EC 62052-31 :201 5 © I EC 201 5
T a b l e 9 – C re e p a g e d i s t a n c e s fo r m a i n s - c i rc u i t s
V a l u e s fo r c re e p a g e d i s t a n c e
P ri n t e d
w i ri n g
b o a rd
O th e r i n s u l a ti n g
m a t e ri a l
m a t e ri a l
Ra ti o n a l i z e d
P o l l u ti o n
v o l t a g e r. m . s .
( fro m
1
2
d e g re e
2 ( i n d o o r m e t e r)
3 ( o u t d o o r m e t e r)
Ta b l e 7 )
M a t e ri a l
I,
II
g ro u p s
or
Al l
I
II
III
I
II
III
IIIa
V
mm
mm
mm
mm
mm
mm
mm
mm
1 00
0, 1 0
0, 1 6
0, 71
1 ,0
1 ,4
1 ,8
2, 0
2, 2
1 60
0, 25
0, 4
0, 8
1 ,1
1 ,6
2, 0
2, 2
2, 5
320
0, 75
1 ,6
1 ,6
2, 2
3, 2
4, 0
4, 5
5, 0
630
1 ,8
3, 2
3, 2
4, 5
6, 3
8, 0
9, 0
10
NOTE 1
The val ues h ave been taken from IEC 60664-1 :2007, Table F. 4.
NOTE 2 Poll ution degree 1 applies if poll ution is redu ced by coati ng, pottin g or m oulding. For m ore
inform ation, see IEC 60664-3:2003.
NOTE The fol lowing paragraph is from I EC 60664-1 : 2007, 5. 2. 2. 6.
I n general, a creepage distance cannot be less than the associated clearance so that the
shortest creepage distance possible is equal to the required clearance. H owever, there is no
ph ysical relationship, other than this dimensional limitation, between the m inim um clearance
in air and the minimum acceptable creepage distance.
Co n form ity is ch e cke d b y in s p e ctio n a n d m e a s ure m e n t.
6. 7. 3. 4
6. 7. 3. 4. 1
Soli d
i n s u l ati o n
fo r m a i n s - c i rc u i t s
G e n e ra l
NOTE 1 Subclause 6. 7. 3. 4 is based on I EC 61 01 0-1 : 201 0, Annex K. 1 . 3.
Solid insulation of mains-circuits shall withstand the electrical and mechanical stresses that
may occur in normal use, in all rated environmental conditions (see 1 . 4), during the intended
life of the equipm ent.
The m anufacturer should take the expected life of the equipm ent into account when selecting
insulating m aterials.
The test voltages are specified for short term s stress in Table 1 0 and for long term stress in
Table 1 1 .
Co n form ity is ch e cke d b y b oth o f th e fo llo win g te s ts:
a)
th e im p ulse vo lta ge te s t sp e cifie d in 6. 1 0. 4 . 4 . 4 . 2 or th e 5 s a . c.
vo lta ge te st s p e cifie d in
6. 1 0. 4. 4. 4 . 3 a ) ;
b)
th e 1 m in a . c. vo lta ge te s t sp e cifie d in 6. 1 0. 4 . 4 . 4 . 4 a ) .
NOTE 2 Th ese two different voltage tests are requi red for these ci rcuits for th e fol l owing reasons. Test a) checks
the effects of transi ent overvol tages, while test b) checks the effects of long -term stress of solid i nsulati on.
I EC 62052-31 :201 5 © I EC 201 5
– 71 –
T a b l e 1 0 – T e s t v o l t a g e s fo r s o l i d i n s u l a t i o n
in
m a i n s - c i rc u i t s
Te s t vo l ta g e
5 s a. c.
vo l ta g e te s t
I m p u l s e te s t
Vo l ta g e l i n e -to n e u tra l
d e ri v e d
n om i n al
V r. m .s.
fro m
V peak
vo l ta g e s
B a s i c i n s u l a ti o n
( fro m
Ta b l e 7 )
B a s i c i n s u l a ti o n
an d
R e i n fo rc e d
an d
R e i n fo rc e d
s u p p l em e n tary
i n s u l a ti o n
s u p p l e m e n tary
i n s u l a ti o n
i n s u l a ti o n
i n s u l a ti o n
< 1 50
1 390
2 21 0
2 500
4 000
> 1 50 ≤ 300
2 21 0
3 51 0
4 000
6 400
> 300 ≤ 600
3 31 0
5 400
6 000
9 600
NOTE The val ues are taken form I EC 61 01 0-1 : 201 0, Table K. 6.
Tabl e 1 1
– T e s t v o l t a g e s fo r t e s t i n g
of s ol i d i n su l ati on
in
l o n g - t e rm
s t re s s
m a i n s - c i rc u i t s
Te s t vo l t a g e
Vo l ta g e l i n e -to n e u tra l
fro m
min
a. c.
vo l ta g e t e s t
1
min
d . c.
V r. m .s.
n om i n al
vo l ta g e s
( fro m
1
d e ri v e d
vo l ta g e te s t
V peak
B a s i c i n s u l a ti o n
B a s i c i n s u l a ti o n
an d
R e i n fo rc e d
an d
Re i n fo rc e d
s u p p l e m e n tary
i n s u l a ti o n
s u p p l em en tary
i n s u l a ti o n
Ta b l e 7 )
i n s u l a ti o n
i n s u l a ti o n
≤ 1 50
1 350
2 700
1 900
3 800
> 1 50 ≤ 300
1 500
3 000
2 1 00
4 200
> 300 ≤ 600
1 800
3 600
2 550
5 1 00
NOTE The values are taken form I EC 61 01 0-1 : 201 0, Table K. 8. The test voltag es for basi c and su ppl em entary
insulati on are derived using th e form ula (1 200 V + li ne-to-neutral voltage) as specified in i n I EC 60664-1 : 2007,
5. 3. 3. 2. 3.
Solid insulation shall also m eet the following requirem ents, as applicable:
1 ) for solid insulation used as an enclosure or barrier, the requirements of Clause 8,
Re s ista n ce to m e ch a n ica l s tre sse s , and 1 0.5, Re sista n ce to h e a t;
2) for moulded and potted parts, the requirements of 6. 7. 3.4.2;
3) for inner layers of printed wiring boards, the requirements of 6.7. 3. 4. 3;
4) for thin-film insulation, the requirem ents of 6. 7. 3. 4.4.
Co n fo rm ity is ch e cke d a s sp e cifie d in 6. 7. 3. 4. 2 to 6. 7. 3. 4 . 4 ,
Cla use 8 a n d sub cla use 1 0. 5 a s
a p p lica b le .
6. 7 . 3 . 4. 2
M ou l d ed
a n d p o t t e d p a rt s
NOTE This subclause reprodu ces I EC 61 01 0-1 : 201 0, Ann ex K. 1 . 3. 2.
For basic insulation, supplementary insulation and reinforced insulation, conductors located
between the same two layers m oulded together (see Figure 6, item L) shall be separated by
at least the applicable m inim um distance of Table 1 2 after the moulding is completed.
Co n form ity
is
ch e cke d
by
in s p e ctio n
and
e ith e r
in sp e ctio n of th e m a n ufa cture r’s s p e cifica tion s .
by
m e a sure m e n t
o f th e
se p a ra tio n
or
by
– 72 –
I EC 62052-31 :201 5 © I EC 201 5
1
L
2
C
IEC
Ke y
1
2
C
L
Layer 1
Layer 2
Con ductor
Distance between conductors
F i g u re 6 – D i s t a n c e b e t w e e n
6. 7. 3 . 4. 3
I n n er i n s u l ati n g
c o n d u c t o rs o n
an
l a y e rs o f p ri n t e d w i ri n g
i n t e rfa c e b e t w e e n
t w o l a y e rs
b o a rd s ( P W B s )
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, Annex K. 1 . 3. 3.
For basic insulation, supplementary insulation and reinforced insulation, conductors located
between the sam e two layers (see Figure 7, item L) shall be separated by at least the
applicable m inim um distance of Table 1 2.
Conformity is checked by inspection and either by measurement of the separation or by
inspection of the manufacturer’s specifications.
d
A
L
C
IEC
Ke y
L
d
A
C
Distance between adj acent con ductors
Thickness of inner insulatin g layer
Layers (For m inim um thickness, see Tabl e 1 2)
Con ductors
F i g u re 7 – D i s t a n c e b e t w e e n
a d j a c e n t c o n d u c t o rs a l o n g
an
i n t e rfa c e o f a n
i n n e r l a ye r
I EC 62052-31 :201 5 © I EC 201 5
– 73 –
Tabl e 1 2 – M in i mu m val u es for di stan ce or th i ckn ess of solid in su lation
Vol tag e l i n e-to-n eu tral
d eri ved from n om i n al
vol tag es
M i n im u m th i ckn ess
(from Tabl e 7)
(see Fi g u re 7)
(see Fi g u re 7)
V
mm
mm
≤ 300
0, 4
0, 75
> 300 ≤ 600
0, 6
1 ,8
d
M i n im u m d i stan ce
a, b
L
a, b
a
These valu es are in depen dent of the overvoltage category.
b
These val ues apply for basic insulation, supplem entary insulati on an d
rei nforced insul ation.
NOTE The values for m inimum thickness d are taken from I EC 61 01 0-1 : 201 0,
Table K. 9. The values for Mi nim um distance L are taken from Table 9, Printed
wiri ng board m ateri al, Polluti on deg ree 1 .
Reinforced insulation of inner insulating layers of printed wiring boards shall also have
adequate electric strength through the respective layers. One of the following methods shall
be used:
a) the thickness through the insulation is at least the value of Table 1 2;
Conformity is checked by inspection and either by measurement of the separation or by
inspection of the manufacturer’s specifications.
b) the insulation is assembled from at least two separate layers of printed wiring board
m aterials, each of which is rated by the manufacturer of the material for an electric
strength of at least the value of the test voltage of Table 1 0 for basic insulation;
Conformity is checked by inspection of the manufacturer’s specifications.
c) the insulation is assembled from at least two separate layers of printed wiring board
m aterials, and the com bination of layers is rated by the manufacturer of the material for an
electric strength of at least the value of Table 1 0 for reinforced insulation.
Conformity is checked by inspection of the manufacturer’s specifications.
No m inim um thickness is specified for basic or supplementary insulation between traces
located on the opposite sides of the same layer of a printed wiring board. H owever, a layer of
printed wiring board material used as basic or supplementary insulation shall be rated by the
m anufacturer of the m aterial for an electric strength of at least the valu e of the test voltage of
Table 7 for basic insulation.
6. 7. 3.4. 4
Th in -fil m in su l ati on
NOTE 1 This subcl ause reproduces I EC 61 01 0-1 : 201 0, Ann ex K. 1 . 3. 4.
For basic insulation, supplementary insulation and reinforced insulation, conductors located
between the sam e two layers (see Figure 8, item L) shall be separated by at least the
applicable clearance of 0, Table 8 and creepage distance of 6. 7.3.3, Table 9.
Conformity is checked by inspection and either by measurement of the separation or by
inspection of the manufacturer’s specifications.
– 74 –
I EC 62052-31 :201 5 © I EC 201 5
L
d
A
C
IEC
Ke y
L
d
A
C
Distance between adj acent con ductors
Thickness of inner insulatin g layer
Layers of th in-fi lm m aterial such as tape and pol yester film
Con ductors
NOTE There m ay be air present between the l ayers.
F i g u re 8 – D i s t a n c e b e t w e e n
l ocated
b e twe e n
a d j a c e n t c o n d u c t o rs
t h e s a m e t w o l a y e rs
Reinforced insulation through the layers of thin-film insulation shall also have adequate
electric strength. One of the following methods shall be used.
a) The thickness through the insulation is at least the value of Table 1 2;
Conformity is checked by inspection and either by measurement of the separation or by
inspection of the manufacturer’s specifications.
b) The insulation consists of at least two separate layers of thin-film m aterials, each of which
is rated by the manufacturer of the material for an electric strength of at least the value of
the test voltages from Table 1 0 for basic insulation.
Conformity is checked by inspection of the manufacturer’s specifications.
c) The insulation consists of at least three separate layers of thin-film m aterials, an y two
which have been tested to exh ibit adequate electric strength of at least the value of the
test voltages from Table 1 0 for reinforced insulation.
Conformity is checked by the a.c. voltage test of 6.10. 4.4.4. 4 b).
For the purposes of this test a special sam ple m ay be assem bled with onl y two layers of
the material.
6. 7. 4
6. 7. 4. 1
I n s u l ati o n
re q u i re m e n t s fo r n o n - m a i n s - c i rc u i t s
G e n e ra l
As defined in 3. 5. 8, non-mains circuits are circuits which are not energized directl y from the
m ains but which are for example isolated by a transform er or suppl ied by a battery.
NOTE These circu its are assum ed to be subj ected to l ower transient overvoltage levels than the m ains-ci rcuit.
6. 7. 4. 2
C l e a ra n c e s fo r n o n - m a i n s - c i rc u i t s
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, K. 2. 2.
Clearances for non - mains-circuits shall:
a) for basic insulation or supplementary insulation, m eet the applicable values of Table 1 3 or
for reinforced insulation meet twice that value; or
b) pass the voltage test of 6.1 0. 4.4. 3 using the applicable value of Table 1 3.
I EC 62052-31 :201 5 © I EC 201 5
– 75 –
For the application of Table 1 3 the following applies:
1 ) values for test voltages for reinforced insulation are 1 ,6 times the values for basic
insulation;
2) if the equipment is rated to operate at an altitude greater than 2 000 m, the values for
clearances are m ultiplied by the applicable factor of Table 5;
3) minim um clearance is 0, 2 mm for pollution degree 2 and 0, 8 m m for pollution degree 3.
Co n form ity is ch e cke d b y in sp e ction a n d m e a sure m e n t a n d fo r b ) b y th e 5 s a . c. vo lta ge te st
or 1 m in d. c. vo lta ge te st of 6. 1 0. 4 . 4. 3.
T a b l e 1 3 – C l e a ra n c e s a n d t e s t v o l t a g e s fo r n o n - m a i n s - c i rc u i t s
d e ri v e d fro m
W o rk i n g
d. c. or a. c.
peak
M a i n s vo l ta g e
M a i n s vo l ta g e
vo l ta g e i n
≤
n o n -m a i n s c i rc u i t
a. c. r. m .s.
m a i n s - c i rc u i t s o f o v e rv o l t a g e c a t e g o ry I I I
1 50 V a. c.
Clearance
V
V
16
22, 6
33
47, 3
50
70
1 00
1 40
1 50
21 0
300
420
600
840
1 000
1 400
1 250
1 750
NOTE The val ues have been
table.
r. m . s .
Test voltage
a. c. r. m .s.
1 50 V
≤
3 0 0 V a. c.
Clearance
r. m . s .
Test voltage
a. c. r. m .s.
mm
V
mm
0, 48
1 1 00
1 ,5
0, 50
1 1 00
1 ,5
0, 53
1 1 20
1 ,5
0, 61
1 1 70
1 ,6
0, 69
1 200
1 ,6
0, 94
1 360
1 ,8
1 ,6
1 880
2, 4
2, 5
2 500
3, 5
3, 2
3 020
4, 2
taken from I EC 61 01 0-1 : 201 0, Table K. 1 1 .
M a i n s vo l ta g e
300 V
≤
60 0 V a. c.
r. m . s .
Test
voltage a. c.
r. m . s.
V
2 820
2 900
2 900
2 960
3 020
3 1 40
3 440
4 000
4 480
voltag es, see that
Clearance
V
mm
1 800
2, 9
1 800
3, 0
1 800
3, 0
1 880
3, 1
1 880
3, 2
2 040
3, 4
2 440
3, 9
3 200
5, 0
3 620
5, 8
For h igh er workin g
Linear i nterpolation above 1 6 V is allowed.
6. 7. 4. 3
C re e p a g e d i s t a n c e s fo r n o n - m a i n s - c i rc u i t s
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, K. 2. 3.
Creepage distances for basic insulation or supplem entary insulation for non - mains-circuits
shall meet the applicable values of Table 1 4, based on the working voltage which stresses the
insulation. Values for reinforced insulation are twice the values for basic insulation.
Where the non-mains-circuit is derived from the mains circuits, then the creepage distance
shall not be less than the clearance as specified in Table 1 3.
Co n form ity is ch e cke d b y in sp e ctio n a n d m e a sure m e n t.
Coatings that m eet the requirements of Annex H of I EC 61 01 0-1 : 201 0 when applied to the
outer surfaces of printed wiring boards reduce th e pollution degree of the coated area to
pollution degree 1 .
T a b l e 1 4 – C re e p a g e d i s t a n c e s fo r n o n - m a i n s - c i rc u i t s
NOTE 2 This tabl e can also be used to determ ine creepage distances for fu nction al insu lati on.
– 76 –
P ri n t e d
w i ri n g
b o a rd
I EC 62052-31 :201 5 © I EC 201 5
O th e r i n s u l a ti n g
m a t e ri a l
m a t e ri a l
S eco n d ary
P o l l u ti o n
d e g re e
w o rk i n g
vo l ta g e
a. c.
1
2
2 ( I n d o o r m e t e rs )
3 ( O u td o o r m e t e rs )
r. m . s .
M a t e ri a l
g ro u p s
or d . c.
I,
II
or
I
Al l
II
III
I
II
III
mm
1 , 00
1 , 05
1 ,1 0
1 , 20
1 , 25
1 ,3
1 ,4
1 ,5
1 ,6
1 ,7
1 ,8
1 ,9
2, 0
2, 5
3, 2
4, 0
5, 0
6, 3
8, 0
1 0, 0
1 2, 5
mm
1 , 00
1 , 05
1 ,1 0
1 , 20
1 , 25
1 ,3
1 ,6
1 ,7
1 ,8
1 ,9
2, 0
2, 1
2, 2
2, 8
3, 6
4, 5
5, 5
7, 1
9, 0
1 1 ,1
1 4, 0
mm
1 , 00
1 , 05
1 ,1 0
1 , 20
1 , 25
1 ,3
1 ,8
1 ,9
2, 0
2, 1
2, 2
2, 4
2, 5
3, 2
4, 0
5, 0
6, 3
8, 0
1 0, 0
1 2, 5
1 6, 0
IIIa
V
mm
mm
mm
mm
mm
10
0, 025
0, 04
0, 40
0, 40
0, 40
1 2, 5
0, 025
0, 04
0, 42
0, 42
0, 42
16
0, 025
0, 04
0, 45
0, 45
0, 45
20
0, 025
0, 04
0, 48
0, 48
0, 48
25
0, 025
0, 04
0, 50
0, 50
0, 50
32
0, 025
0, 04
0, 53
0, 53
0, 53
40
0, 025
0, 04
0, 56
0, 80
1 ,1 0
50
0, 025
0, 04
0, 60
0, 85
1 , 20
63
0, 040
0, 063
0, 63
0, 90
1 , 25
80
0, 063
0, 1 0
0, 67
0, 95
1 ,3
1 00
0, 1 0
0, 1 6
0, 71
1 , 00
1 ,4
1 25
0, 1 6
0, 25
0, 75
1 , 05
1 ,5
1 60
0, 25
0, 40
0, 80
1 ,1
1 ,6
200
0, 40
0, 63
1 , 00
1 ,4
2, 0
250
0, 56
1 ,0
1 , 25
1 ,8
2, 5
320
0, 75
1 ,6
1 ,6
2, 2
3, 2
400
1 ,0
2, 0
2, 0
2, 8
4, 0
500
1 ,3
2, 5
2, 5
3, 6
5, 0
630
1 ,8
3, 2
3, 2
4, 5
6, 3
800
2, 4
4, 0
4, 0
5, 6
8, 0
1 000
3, 2
5, 0
5, 0
7, 1
1 0, 0
NOTE 1 The val ues h ave been taken from I EC 60664-1 : 2007, Tabl e F. 4.
NOTE 2 The val ues in th e sh aded lin es are the sam e as in Table 9.
Linear i nterpolation is all owed from 1 0 V up.
6. 7. 4. 4
6. 7. 4. 4. 1
Sol id
i n s u l a ti o n
fo r n o n - m a i n s - c i rc u i t s
G e n e ra l
NOTE This subcl ause 6. 7. 4. 4 is based on I EC 61 01 0-1 : 201 0, K. 2. 4.
Solid insulation for non-mains circuits shall withstand the electrical and mechanical stresses
that may occur in normal use, in all rated environmental conditions (see 1 . 4), during the
intended life of the equipm ent.
The m anufacturer should take the expected life of the equipment into account when selecting
insulating m aterials.
Co n fo rm ity is ch e cke d b y b oth o f th e fo llo win g te s ts:
a)
th e 5 s a . c. vo lta ge te s t sp e cifie d in 6. 1 0. 4. 4. 4. 3 b ) usin g th e a p p lica b le te st vo lta ge s fro m
Ta b le 1 3 for b a sic in sula tio n a n d sup p le m e n ta ry in sula tio n .
For re in fo rce d in sula tion ,
th e
va lue s a re m ultip lie d b y 1 , 6;
b)
a dditio n a lly, if th e workin g vo lta ge e xce e ds 300 V, b y th e 1 m in a . c. vo lta ge te st sp e cifie d
in 6. 1 0. 4. 4 . 4 . 4 c) , with a te st vo lta ge o f 1 , 5 tim e s th e wo rkin g vo lta ge for b a s ic in s ula tion
a n d sup p le m e n ta ry in sula tion a n d twice th e wo rkin g volta ge for re in force d in sula tion .
Solid insulation shall also m eet the following requirements, as applicable:
I EC 62052-31 :201 5 © I EC 201 5
– 77 –
1 ) for solid insulation used as an enclosure or barrier, the requirem ents of Clause 8,
Re s ista n ce to m e ch a n ica l s tre sse s ;
2) for moulded and potted parts, the requirements of 6. 7. 4.4.2;
3) for inner insulating layers of printed wiring boards, the requirements of 0;
4) for thin-film insulation, the requirem ents of 6. 7. 4. 4. 4.
Co n fo rm ity is ch e cke d a s sp e cifie d in 6. 7. 4. 4 . 2 to 6. 7. 4 . 4 . 4 a n d in Cla us e 8 a s a p p lica b le .
6. 7 . 4. 4. 2
M ou l d ed
a n d p o t t e d p a rt s
For basic insulation, supplementary insulation and reinforced insulation, conductors located
between the sam e two layers m oulded together (see Figure 6, item L) shall be separated by
the applicable minimum distance of Table 1 5 after the moulding is completed.
Co n form ity
is
ch e cke d
by
in sp e ctio n
and
e ith e r
by
m e a sure m e n t
o f th e
se p a ra tio n
or
by
in sp e ctio n o f th e m a n ufa cture r’s s p e cifica tion s.
T a b l e 1 5 – M i n i m u m v a l u e s fo r d i s t a n c e
o r t h i c kn e s s ( s e e 6 . 7 . 4 . 4 . 2 t o 6 . 7 . 4 . 4 . 4 )
P e a k va l u e o f th e a . c.
or d . c.
w o rk i n g
M inimum
v o l t a g e o r re c u r ri n g
va l u e
p e a k vo l ta g e
V
mm
≤ 330
0, 01
> 330 ≤ 400
0, 02
> 400 ≤ 500
0, 04
> 500 ≤ 600
0, 06
> 600 ≤ 800
0, 1 0
> 800 ≤ 1 000
0, 1 5
> 1 000 ≤ 1 200
0, 2
> 1 200 ≤ 1 500
0, 3
> 1 500 ≤ 2 000
0, 45
> 2 000 ≤ 2 500
0, 6
> 2 500 ≤ 3 000
0, 8
> 3 000 ≤ 4 000
1 ,2
> 4 000 ≤ 5 000
1 ,5
> 5 000 ≤ 6 000
2
> 6 000 ≤ 8 000
3
NOTE 1
Th e val ues have been taken from IEC 60664-3:2003, Tabl e 1 , Min im u m
2 p ro te ctio n on which I EC 61 01 0-1 : 201 0, Table K. 1 4 is based .
For hi gh er voltages, see th at table.
sp a cin gs
fo r typ e
NOTE 2 Type 2 protection is considered to be sim il ar to soli d insulati on.
6. 7. 4. 4. 3
I n n e r i n s u l a ti n g
l a y e rs o f p ri n t e d w i ri n g
b o a rd s
For basic insulation, supplementary insulation and reinforced insulation conductors located
between the same two layers (see Figure 7, item L) shall be separated by the applicable
minim um distance of Table 1 5.
Co n form ity
is
ch e cke d
by
in s p e ctio n
and
e ith e r
in sp e ctio n of th e m a n ufa cture r’s s p e cifica tion s .
by
m e a sure m e n t
o f th e
se p a ra tio n
or
by
– 78 –
I EC 62052-31 :201 5 © I EC 201 5
Reinforced insulation of inner insulating layers of printed wiring boards shall also have
adequate electric strength through the respective layers. One of the following methods shall
be used:
a) the thickness of the insulation is at least the applicable m inimum distance of Table 1 5;
Co n form ity is ch e cke d b y in s p e ctio n a n d e ith e r b y m e a sure m e n t o f th e se p a ra tio n or b y
in sp e ctio n of th e m a n ufa cture r’s s p e cifica tion s .
b) the insulation is assembled from at least two separate layers of printed wiring board
m aterials, each of which is rated by the manufacturer of the m aterial for an electric
strength at least the value of the test voltage of Table 1 3 for basic insulation.
Co n form ity is ch e cke d b y in sp e ctio n o f th e m a n ufa cture r’s sp e cifica tio n s .
c) the insulation is assembled from at least two separate layers of printed wiring board
m aterials, and the combination of layers is rated by the m anufacturer of the m aterial for an
electric strength at least the value of the test voltage of Table 1 3 m ultiplied by 1 , 6 for
reinforced insulation.
Co n form ity is ch e cke d b y in s p e ctio n o f th e m a n ufa cture r’s s p e cifica tion s .
6. 7. 4. 4. 4
T h i n - fi l m
i n s u l ati on
For basic insulation, supplem entary insulation and reinforced insulation conductors located
between the sam e two layers (see Figure 8, item L) shall be separated by at least the
applicable clearance and creepage distance of 6.7. 4.2 and 6. 7.4. 3.
Co n form ity
is
ch e cke d
by
in s p e ctio n
and
e ith e r
by
m e a s ure m e n t
o f th e
se p a ra tio n
or
by
in sp e ctio n of th e m a n ufa cture r’s s p e cifica tion s .
Reinforced insulation through the layers of thin-film insulation shall also have adequate
electric strength. One of the following m ethods shall be used:
a) the thickness through the insulation is at least the applicable value of Table 1 5;
Co n form ity is ch e cke d b y in sp e ctio n a n d e ith e r b y m e a sure m e n t o f th e se p a ra tio n or b y
in sp e ctio n of th e m a n ufa cture r’s s p e cifica tion s .
b) the insulation consists of at least two separate layers of thi n-film m aterials, each of which
is rated by the m anufacturer of the m aterial for an electric strength at least the value of
the test voltage of Table 1 3 for basic insulation;
Co n form ity is ch e cke d b y in s p e ctio n o f th e m a n ufa cture r’s s p e cifica tion s.
c) the insulation consists of at least three separate layers of thin-film materials, an y two of
which have been tested to exhibit adequate electric strength.
Co n form ity is ch e cke d b y th e
1
m in
a . c.
vo lta ge
te s t o f 6. 1 0. 4 . 4. 4. 4
d)
or –
for circuits
stre ss e d on ly b y DC – th e 1 m in d. c. vo lta ge th e te st o f 6. 1 0. 4 . 4 . 4 . 5.
For the purposes of the test for option c), a special sample m ay be assembled with onl y
two layers of the m aterial.
6. 7. 5
6. 7. 5. 1
I n s u l ati o n
in
c i rc u i t s n o t a d d re s s e d
in
0 or 6. 7. 4
G e n e ra l
NOTE Subclause 6. 7. 5 is based on I EC 61 01 0-1 : 201 0, Cl au se K. 3.
These circuits have one or more of the following characteristics:
a) the m axim um possible transient overvoltage is lim ited by the suppl y source or within the
equipment (see 6.7. 6) to a known level below the level assum ed for the m ains circuit;
b) the maximum possible transient overvoltage is above the level assumed for the m ains
circuit;
c) the working voltage is the sum of voltages from more than one circuit, or is a m ixed
voltage;
I EC 62052-31 :201 5 © I EC 201 5
– 79 –
d) the working voltage includes a recurring peak voltage that may include a periodic nonsinusoidal waveform or a non-periodic waveform that occurs with som e regularity;
e) the working voltage has a frequency above 30 kH z.
In cases a) to c), clearances for basic insulation and supplementary insulation are determ ined
according to 6. 7. 5. 2.
In cases d) and e) clearances are determined according to 6. 7. 5. 3.
In all cases 0 addresses creepage distance and 6. 7. 5. 5 solid insulation.
6.7.5.2
Clearance calculation
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, K. 3. 2.
Clearances for basic insulation and supplem entary insulation are determined from the
following form ula:
Clearance =
퐷 1 + 퐹 × (퐷2 − 퐷1 )
where
퐹
is a factor, determined from one of the form ulas:
퐹 = �1,25 × 푈푈w � − 0,25
if
푈w /푈m 0,2
퐹=0
if
푈w /푈m 0,2
m
where
푈m = 푈w + 푈t
where
푈w is the m aximum peak value of the working voltage;
푈t is the maximum additional transient overvoltage;
퐷1 and 퐷2 are values taken from Table 1 6 for 푈m .
where
•
•
퐷1 represents the clearance that would be applicable to a transient overvoltag e with the
shape of a 1 , 2 / 50 µ s impulse.
퐷2 represents the clearance that would be applicable to the peak working voltage without
an y transient overvoltage;
Clearances for reinforced insulation are twice the values for basic insulation.
I f the equipment is rated to operate at an altitude greater than 2 000 m, the clearances shall
be m ultiplied by the applicable factor of Table 5.
Minimum clearance, for basic insulation, supplem entary insulation and reinforced insulation,
is 0,2 mm for pollution degree 2 and 0, 8 mm for pollution degree 3.
Conformity is checked by inspection and measurement or by the test specified in 6. 1 0. 4. 4. 5.
– 80 –
I EC 62052-31 :201 5 © I EC 201 5
Table 1 6 – Clearance values for the calculation of 6.7.5.2
Maximum
voltage
Clearance
Clearance
Um
D1
mm
V
mm
mm
0, 01 0
0, 01 0
4 000
2, 93
6, 05
283
0, 01 0
0, 01 3
4 530
3, 53
7, 29
330
0, 01 0
0, 020
5 660
4, 92
1 0, 1
354
0, 01 3
0, 025
6 000
5, 37
1 0, 8
453
0, 027
0, 052
7 070
6, 86
1 3, 1
500
0, 036
0, 071
8 000
8, 25
1 5, 2
566
0, 052
0, 1 0
8 91 0
9, 69
1 7, 2
707
0, 081
0, 20
1 1 300
1 2, 9
22, 8
800
0, 099
0, 29
1 4 1 00
1 6, 7
29, 5
891
0, 1 2
0, 41
1 7 700
21 , 8
38, 5
Um
D1
V
mm
1 4, 1 to 266
D2
Maximum
voltage
D2
1 1 30
0, 1 9
0, 83
22 600
29, 0
51 , 2
1 41 0
0, 38
1 , 27
28 300
37, 8
66, 7
1 500
0, 45
1 , 40
35 400
49, 1
86, 7
1 770
0, 75
1 , 79
45 300
65, 5
116
2 260
1 , 25
2, 58
56 600
85, 0
1 50
2 500
1 , 45
3, 00
70 700
110
1 95
2 830
1 , 74
3, 61
89 1 00
1 45
255
3 540
2, 44
5, 04
1 00 000
1 65
290
Linear i nterpolation is allowed from 1 4,1 V up.
Table 1 7 shows test voltages based on clearances.
I EC 62052-31 :201 5 © I EC 201 5
– 81 –
T ab l e 1 7 – T e s t vo l tag e s b a s e d o n
Re q u i re d
c l e a ra n c e
Te s t vo l ta g e
I m pu l se
1 , 2 /5 0
NOTE 1
c l e a ra n c e s
µ
s
a. c.
r. m . s .
5 0 /6 0 H z
mm
V peak
V r. m .s
0, 01 0
330
230
0, 025
440
31 0
0, 040
520
370
0, 063
600
420
0, 1
81 0
500
0, 2
1 1 50
620
0, 3
1 31 0
71 0
0, 5
1 550
840
1 ,0
1 950
1 060
1 ,5
2 560
1 390
2, 0
3 090
1 680
2, 5
3 600
1 960
3, 0
4 070
2 21 0
4, 0
4 930
2 680
4, 5
5 330
2 900
5, 0
5 720
3 110
6, 0
6 460
3 51 0
8, 0
7 840
4 260
1 0, 0
9 1 00
4 950
1 2, 0
1 0 600
5 780
1 5, 0
1 2 900
7 000
20
1 6 400
8 980
25
1 9 900
1 0 800
30
23 300
1 2 700
40
29 800
1 6 200
50
36 000
1 9 600
60
42 000
22 800
80
53 700
29 200
1 00
65 000
35 400
The val ues are taken from I EC 61 01 0-1 : 201 0, Table K. 1 6
Linear i nterpolation is allowed from 0,01 0 mm up.
EXAMPLE 1 :
Clearance for reinforced insul ation for a working voltage wi th peak value of 3 500 V and an additi on al transi ent
voltage of 4 500 V (this can be expected within an electronic switchi ng -circuit):
Maxim um voltage 푈m = 푈w + 푈t
= (3 500 + 4 500) V = 8 000 V
푈w /푈m = 3 500 / 8 000 = 0, 44 > 0, 2
thus 퐹 = �1,25 × 푈푈w � − 0,25 = 1 , 25 x 3 500 / 8 000 – 0, 25 = 0, 297
m
– 82 –
I EC 62052-31 :201 5 © I EC 201 5
Values d eri ved from Tabl e 1 6 at 8 000 V:
퐷 1 = 8, 25 m m , 퐷 2 = 1 5, 2 mm
퐶퐶퐶 퐶퐶퐶퐶퐶퐶 = 퐷 1 + 퐹 × (퐷 2 − 퐷 1 ) = 8, 25 + 0, 297 × (1 5, 2 – 8, 25) = 8, 25 + 2, 06 = 1 0, 3 m m
For reinforced insul ation the value is doubl ed. Cl earance = 20, 6 mm .
EXAMPLE 2:
Clearance for basic insul ation for a circuit driven from a m ains transform er conn ected to an outlet of the distribution
system with a m ains voltag e of 230 V and overvoltag e categ ory I I . The circuit includ es transient overvoltage
lim iting devices (see 6. 7. 6) whi ch lim it the m axim um voltage (i ncludi ng transients) in th e circuit to 1 000 V.
The peak valu e 푈w of the voltage in the circu it is 1 50 V.
The m axim um value of th e voltage 푈푚 = 1 000 V.
푈w /푈m = 1 50 / 1 000 = 0, 1 5
< 0, 2, thu s F = 0.
Clearance 퐷1 = 0, 1 5 mm interpol ated from Table 1 6.
The clearance is then corrected for altitud e an d checked agai nst polluti on d eg ree m inim um cl earances.
6.7.5.3
Clearances in circuits having recurring peak voltages, or having working
voltages with frequencies above 30 kHz
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, K. 3. 3.
Clearances for basic insulation and supplem entary insulation for circuits having recurring
peak voltages but not subj ected to frequencies above 30 kH z shall m eet the values of th e
second colum n of Table 1 8 using the recurring peak voltage as the index. (See Figure 9 for an
exam ple of a recurring peak voltage.)
U
A
B
t
IEC
Key
A
B
Peak val ue of recu rri ng vol tage
Working voltage val ue
Figure 9 – Example of recurring peak voltage
Clearances for basic insulation and supplementary insulation for circuits that are subjected to
frequencies above 30 kH z shall meet the values of the third column of Table 1 8 using the
peak value of the working voltage as the index.
Clearances for basic insulation and supplementary insulation for circuits that m ay be
subj ected to both recurring peak voltages and to frequencies above 30 kH z shall meet the
higher of these requirements.
Clearances for reinforced insulation are twice the values for basic insulation.
I EC 62052-31 :201 5 © I EC 201 5
– 83 –
I f the equipment is rated to operate at an altitude greater than 2 000 m, the clearances are
multiplied by the applicable factor of Table 5.
The minimum clearance, for basic insulation, supplem entary insulation and reinforced
insulation, is 0, 2 m m for pollution degree 2 and 0, 8 mm for pollution degree 3.
Conformity is checked by inspection and measurement.
Table 1 8 – Clearances for basic insulation in circuits
having recurring peak voltages
Voltage
Frequencies
up to 30 kHz
Clearances
Frequencies
above 30 kHz
V peak
mm
mm
0 to 330
0, 01
0, 02
400
0, 02
0, 04
500
0, 04
0, 07
600
0, 06
0, 1 1
800
0, 1 3
0, 26
1 000
0, 26
0, 48
1 200
0, 42
0, 76
1 500
0, 76
1 ,1
2 000
1 , 27
1 ,8
2 500
1 ,8
2, 6
3 000
2, 4
3, 5
4 000
3, 8
5, 7
5 000
5, 7
8
6 000
7, 9
10
8 000
11
15
1 0 000
1 5, 2
20
1 2 000
19
25
1 5 000
25
32
20 000
34
44
25 000
44
58
30 000
55
72
40 000
77
1 00
50 000
1 00
–
NOTE The values for frequ encies u p to 30 kHz correspond to I EC 60664-1 : 2007, Table F. 7a, Case A,
inhom ogeneous fiel d cond ition s.
Linear i nterpolation is all owed from 330 V up.
6.7.5.4
Creepage distances
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, K. 3. 4.
The requirem ents of 6.7. 4. 3, creepage distances for non - m ains-circuits, apply.
Conformity is checked as specified in 6. 7. 4. 3.
6.7.5.5
Solid insulation
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, K. 3. 5.
– 84 –
I EC 62052-31 :201 5 © I EC 201 5
The requirem ents of 6. 7. 4. 4 appl y except that in 6.7. 4. 4. 1 a), 0 b) and c), and 6.7. 4. 4. 4 b) and
c) the values of Table 1 7 are used in place of the applicable values of
Table 1 3.
To determ ine the required test voltage from Table 1 7 the following procedure shall be applied:
a) calculation of the theoreticall y required clearance according to 6. 7. 5. 2 considering the
requirem ents of 6.7. 5. 3. Minimum clearances for pollution degrees 2 and 3 do not appl y.
b) application of the resulting theoreticall y required clearance value of Table 1 7 to determine
the required test voltage.
Co n form ity is
ch e cke d a s
sp e cifie d in
6. 7. 4 . 4 ,
usin g
th e
te s t vo lta ge
de te rm in e d a b ove
in
p la ce o f th e te st vo lta ge fro m Ta b le 1 3.
6. 7. 6
Re d u c t i o n
o f t ra n s i e n t o v e rv o l t a g e s b y t h e u s e o f o v e rv o l t a g e l i m i t i n g d e v i c e s
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, Clause K. 4.
Transient overvoltages in a circuit m ay be lim ited by combinations of circuits or com ponents.
Com ponents suitable for this purpose include varistors and gas-filled surge arrestors. See
also 1 3.5.
When such com ponents are used, clearances may be reduced to withstand an impulse
voltage one step lower in the preferred series of im pulse voltages. See Table 7, note b).
EXAMPLE 1 For an i nd oor m eter with n om inal vol tage 3 x 230 / 400 V, the rated im pulse voltag e for basic
insulati on is 4 000 V, see Tabl e 7, and th e req uired clearance is 3, 0 m m , see Tabl e 8. I f a varistor is used then the
clearance m ay be reduced to 1 , 5 mm .
EXAMPLE 2 For th e sam e meter, th e rated im pulse voltage for rei nforced i nsulati on is 6 000 V, see Tabl e 7, an d
the requi red clearance is 5, 5 m m . I f a varistor is used th en th e clearance m ay be reduced to 3, 0 mm .
Co n form ity is ch e cke d b y m e a sure m e n t a n d b y p e rform in g th e im p uls e vo lta ge te st sp e cifie d
in 6. 1 0. 3. 5 with th e te s t vo lta ge s re duce d b y o n e ste p ,
o n a sa m p le fro m wh ich th e va risto rs
h a ve b e e n re m ove d.
6. 8
I n s u l ati o n
re q u i re m e n t s b e t w e e n
c i rc u i t s a n d p a rt s
NOTE 1 This subcl ause is based on I EC 60255-27: 201 3, An nex A.
This subclause provides guidance on the isolation class and insulation requirements:
•
•
on the one hand between these circuits; and on the other hand
between these circuits and accessible parts.
Typical exam ples are provided in Annex B.
The insulation requirements should be used to determ ine the required clearances, creepage
distances and solid insulation from 6.7.
The following m ains circuits shall be considered as hazardous live (HLV) circuits:
•
voltage and current circuits of direct connected and transform er operated meters;
NOTE 2 Cu rrent circu its of CT operated m eters are generall y earth ed.
•
•
•
neutral circuits;
relays / control switches switching mains voltage;
auxiliary suppl y circuits intended for connection to the mains.
Non - m ains-circuits are classified by their working voltage and isolation class as; see Table 1 9:
I EC 62052-31 :201 5 © I EC 201 5
•
•
•
•
•
– 85 –
hazardous live voltage (HLV) circuits (circuits with voltage levels exceeding the values of
6. 3. 2);
extra low voltage (ELV) circuits;
safety extra low voltage (SELV) circuits;
protective extra low voltage (PELV) circuits;
protection by equipotential bonding (PEB) circuits.
T ab l e 1 9 – I s o l a ti o n
C i rc u i t
c l a s s e s fo r n o n - m a i n s - c i rc u i t s
D e s c ri p t i o n
i s o l a ti o n
cl as s
HLV
Non -m ains-circuits exceedin g 33 V r. m . s. a. c. or 70 V d. c. , i. e. ELV voltage lim its.
Hazardous
Live Voltage
ELV
Extra l ow
vol tage
Non -m ains-circuits com plyi ng with the followin g un der norm al operational conditi ons:
– not exceeding 33 V r. m . s. a. c. or 70 V d. c. i. e. ELV vol tage li m its;
– separated from HLV circuits by at least basic insul ation.
See Ann ex B.
ELV circuits should not be accessible u nder n orm al operation al conditi ons.
Exam ples are:
– non -m ains circuits;
– anal og ue/di gital i nputs and outputs, com plying with ELV voltage lim its;
– connections to ELV term ination s of other products.
SELV
Safety extra
low voltage
Non -m ains-circuits com plyi ng with ELV voltage lim its and the followi ng conditi ons:
– separated from HLV circuits by reinforced/doubl e insul ation;
– there shall be n o provision for an earth connecti on.
See Ann ex B.
SELV circuits m ay be accessible an d are safe to touch un der both norm al operational and
single-fau lt conditi ons.
Con nection of an earth to a SELV circuit is not perm itted; for exam ple, connection to an earthed
cable screen or earth ed com munication circuit is n ot perm itted. Where this is requ ired, the
circuit defi nition sh oul d change to PELV.
An exception could be for a PELV system earthed at on e en d of a cable run, it would be
perm issible to connect an SELV system at the other end.
Exam ples are:
– anal og ue/di gital i nputs and outputs which m ay be con nected directly to u nearth ed
comm unication networks or circuits;
– SELV ports which are suitable for con nection to SELV ports of other products.
PELV
Protective
extra low
vol tage
Non -m ains-circuits com plyi ng with ELV voltage lim its and the followi ng conditi ons:
– PELV circuits shall be separated from HLV circuits by reinforced/doubl e insul ation;
– PELV circuits m ay be connected to functional earth, the protective (earth) conductor, or have
provision for an earth conn ection.
See Ann ex B.
PELV circuits m ay be accessible an d are safe to touch un der both n orm al operational and si ngl e
fault cond itions.
Exam ples are:
– anal og ue/di gital i nputs and outputs which m ay be con nected directly to com m unication
networks or circuits;
– PELV ports which are suitable for con nection to PELV ports of other products.
– 86 –
C i rc u i t
I EC 62052-31 :201 5 © I EC 201 5
D e s c ri p t i o n
i s o l a ti o n
cl as s
PEB
Non -m ains-circuits com plyi ng with ELV voltage lim its and the followi ng conditi ons:
– basic protection against electri c shock is provid ed by basic in sulation separati ng H LV circuits
from PEB circuits;
– for fault protection, PEB circuits and accessible conducti ve parts, shall be bon ded to the
protective cond uctor term inal which will prevent hazard ous li ve voltages in PEB circuits.
Protection
by
equi potential
bondin g
See Ann ex B.
PEB circuits m ay be accessibl e an d are safe to touch un der both n orm al operational and si ngle
fault cond itions.
PEB circuits m ay be consid ered as protective earthed circuits or earth ed accessibl e parts for the
purposes of Tabl e 20.
Exam ples are:
– anal ogue/di gital i nputs and outputs which m ay be con nected directly to com m unication
networks or circuits;
– PEB ports which are suitabl e for con nection to PEB ports of other prod ucts.
Table 20 shows the insulation requirem ents between an y two circuits.
T ab l e 2 0 – I n s u l a ti o n
H LV
E L V c i rc u i t
S ELV
PE LV
c i rc u i t
c i rc u i t
a n y t w o c i rc u i t s
P E B c i rc u i t
2)
m ai n sc i rc u i t
re q u i re m e n t s b e t w e e n
1 )
P ro t e c t i v e
U n e a rt h e d
e a rth e d
H LV n on -
H LV n on -
c i rc u i t
F/B
H LV m ai n s-
1 ) 6)
Table 8
Table 9
1 )
c i rc u i t
B
D, R
Table 8
Table 9
S E L V c i rc u i t
D, R
P E L V c i rc u i t
2)
Table 8
Table 9
B
P E B c i rc u i t
2)
P ro t e c t i v e
e a rt h e d
H LV
n o n -m a i n s
c i rc u i t
2),
3)
U n e a rt h e d
H LV n on m a i n s c i rc u i t
3)
P ro t e c t i v e
e a rt h e d
acces si bl e
p a rt
2),
7)
U n e a rt h e d
acces si bl e
p a rt
7)
D, R
D, R
Table 8
Table 9
Table 8
Table 9
Table 8
Table 9
B, S
B, S
Table 1 3
Table 1 4
Table 1 3
Table 1 4
F/B
Table 8
Table 9
E L V c i rc u i t
B
5)
Table 8
Table 9
B
Table 8
Table 9
B
Table 1 3
Table 1 4
B
Table 8
Table 9
D, R
Table 8
Table 9
6)
Table 1 3
Table 1 4
B, S
Table 1 3
Table 1 4
B, S
F/B
6)
Table 1 3
Table 1 4
F/B
8)
F/B
8)
Table 1 3
Table 1 4
F/B
6)
5)
2),
m ai n s
3)
m ai n s-
c i rc u i t
3)
B
B
Table 8
Table 9
Table 8
Table 9
B
B
Table 1 3
Table 1 4
Table 1 3
Tabl e 1 4
Table 1 3
Table 1 4
B
D, R
D, R
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
D, R
D, R
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
B
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
Table 8
Table 9
F/B
5), 6)
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
B
Table 1 3
Table 1 4
Tabl e 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
D, R
D, R
B
Table 8
Table 9
Table 8
Table 9
Table 8
Table 9
Table 8
Table 9
Table 8
Table 9
B
D, R
D, R
B
B
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
B
B
B
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
B
B
B
D, R
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
Table 1 3
Table 1 4
F/B
5), 6)
F/B
6)
F/B
F/B
F/B
6)
Table 1 3
Table 1 4
5)
F/B
6)
6)
B
Table 8
Table 9
F/B
6)
B/D, R
4)
Table 1 3
Table 1 4
I EC 62052-31 :201 5 © I EC 201 5
– 87 –
Abbrevi ations for insu lations:
B: Basic insulation; S: Supplem entary i nsulati on; D: Dou ble i nsulation, R: Reinforced insul ation
F: Function al insul ation
1 ) I f the function al voltage (not relative to earth/groun d) is g reater than the rated insu lation voltage, th e
creepag e distance for th e functional insul ation m ay be g reater than that for th e basic insul ati on. An exam ple
is a term inal bl ock of a three-phase m etering equipm ent with Un = 230/400 V, wh ere the fu n ctional phase-tophase voltage is 400 V r. m . s. For an ind oor m eter with m ateri al grou p I I I , the creepage distance for basic
insulati on from Table 9 is 3, 2 mm , but the creepage d istance for functional i nsulati on from Table 1 4 is
4, 0 mm .
2) Con nections to the protective conductor sh all com ply with 6. 5. 2. 4. Otherwise, this shall be considered to be
an u nearth ed circuit.
3) There shall be at l east basic in sulation between HLV non -m ains circuits and H LV m ains circuits.
4) I nsulation between an unearthed n on -m ains circuit at hazard ous voltage an d an unearthed accessible
conducti ve part shall satisfy th e m ore on erous of the followin g:
– dou ble/rei nforced insu lation, th e working voltag e of wh ich is equal to the h azardous voltage; or
– supplem entary insu lation, the worki ng voltag e of which is equal to th e voltage between the n on -m ains
circuit at hazard ous voltage; and
•
another non-m ains circuit at h azardous voltag e; or
•
a m ains circuit.
5) See Ann ex B for the con ditional use of basic insul ation for PEB.
6) Suppl em entary or basic insul ation shall be used if one of th e circuits is an ind epend ent circuit or is adjacent
to a cond uctive part which m ay be earth ed when the equi pm ent is installed.
7) A functional earthed circuit shall be treated as an unearth ed accessible part. The exception is where th e
function al earth is bon ded to the protecti ve cond uctor and th is m eets the relevant requi rem ents, then it m ay
be treated as an earthed accessible part.
8) For a PELV system earthed at one end of a cable run, it would be perm issible to con nect a SELV system at
the oth er end.
NOTE Reference is m ade to the respective tabl es specifyi ng cl earances an d creepage distances.
Based on this:
•
•
•
•
basic insulation is required between the case of a protective class I equipm ent and the
HLV mains-circuits or H LV non-m ains-circuits;
double insulation is required between the case of protective class I I equipm ent and the
HLV mains-circuits or H LV non-mains-circuits. See also 6. 1 0. 4. 3. 2 , item b);
the clearance between the terminal cover, if made of m etal, and the upper surface of the
term inal screws when screwed down to the maximum applicable conductor fitted shall
meet the requirements for basic insulation for protective class I equipment m eters and
double insulation for protective class I I equipment;
the insulation between:
– non-m ains-circuits and other circuits;
– non-m ains-circuits and the accessible parts;
shall be dim ensioned according to the isolation class of the non-m ains-circuit.
Annex B provides som e examples.
– 88 –
6. 9
C o n s t ru c t i o n a l
6. 9. 1
re q u i re m e n t s fo r p ro t e c t i o n
I EC 62052-31 :201 5 © I EC 201 5
a g a i n s t e l e c t ri c s h o c k
G e n e ra l
NOTE 1 This subcl ause reproduces I EC 61 01 0-1 : 201 0, 6. 9. 1 .
I f a failure could cause a hazard:
a) the security of wiring connections subject to m echanical stresses shall not depend on
soldering;
b) screws securing rem ovable covers shall be captive if their length determines a clearance
or creepage distance between accessible conductive parts and hazardous live parts;
c) accidental loosening or freeing of the wiring, screws, etc., shall not cause accessible parts
to become hazardous live;
d) clearances and creepage distances between the enclosure and hazardous live parts shall
not be reduced below the values for basic insulation by loosening of parts or wires.
NOTE 2 Screws or n uts with lock wash ers are not reg ard ed as liable to becom e loose, n or are wi res wh ich are
m echanically secu red by m ore than sol derin g alone.
Co n form ity is ch e cke d b y in s p e ctio n a n d m e a s ure m e n t o f cle a ra n ce s a n d cre e p a ge dis ta n ce s.
6. 9. 2
I n s u l ati n g
m a t e ri a l s
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 9. 2.
The following shall not be used as insulation for safety purposes:
a) materials which can easil y be damaged (for exam ple, lacquer, enam el, oxides, anodic
film s);
b) non-impregnated h ygroscopic m aterials (for exam ple, paper, fibres, fibrous materials).
Co n form ity is ch e cke d b y in s p e ctio n .
6. 9. 3
C ol o u r co d i n g
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 6. 9. 3.
Green-and-yellow insulation shall not be used except for:
a)
b)
c)
d)
protective earth conductors;
protective bonding conductors;
potential equalization conductors for safety purposes;
functional earth conductors.
Co n fo rm ity is ch e cke d b y in s p e ctio n .
6. 9. 4
E q u i p m en t ca s e
Hazardous live parts shall be located within the equipm ent case.
I f the equipm ent case has removable covers, they shall be firm ly secured in place in such a
way that:
a) they m ay onl y be removed by using a tool;
b) if protected by seals, they cannot be rem oved without breaking the seals.
NOTE 1 I f th e covers are fi xed by screws these are generally protected by seals so that the covers cannot be
rem oved with out breaking the seals first then usi ng a tool to l oosen / fasten the screws.
I EC 62052-31 :201 5 © I EC 201 5
– 89 –
NOTE 2 Som e m etering equi pm ent is “sealed for life”, so th at the case can be only opened by breakin g it.
NOTE 3 This requ irem ent d oes not appl y to covers within th e m eter enclosu re.
Term inals that are hazardous live shall be covered by term inal covers, enclosing the actual
term inals, the conductor fixing screws and, unless otherwise agreed by the m anufacturer and
the purchaser, a suitable length of the external conductors and their insulation, so that no
hazardous live terminals become accessible without rem oving the term inal cover. Term inal
covers shall be firm ly secured in place as specified above.
Panel m ounted m eters do not have to be equipped with terminal covers, if access to
hazardous live term inals in normal operating condition is prevented by an appropriate barrier.
Co n form ity is ch e cke d b y in s p e ctio n a n d if n e ce ss a ry, th e te s ts sp e cifie d in 6. 2 a n d 6. 3.
Term inal covers covering term inals intended for connecting devices by the use r do not need
to be protected against removal. Terminals located under terminal covers that can be
rem oved by a user shall be safe to touch (SELV, PELV or PEB). See 6. 8.
Terminals may be grouped in connectors to prevent access to the term inals.
I t shall not be possible to rem ove socket-mounted equipment from its specified m atching
socket without breaking a seal.
The case shall have sufficient m echanical strength, stability and durability to maintain the
specified degree of protection and shall m eet the rigidity requirem ents specified in 8. 2.
The equipment case, including the covers and term inal covers shall provide a degree of
protection as specified in Clause 1 1 .
Co n form ity is ch e cke d b y in s p e ctio n a n d th e te sts o f 8. 2, 1 0. 5. 1 , 1 0. 5. 2 a n d Cla us e 1 1 .
6. 9. 5
T e rm i n a l
b l o c ks
NOTE This subcl ause is based on I EC 62052-1 1 : 2003, 5. 4.
Term inals m ay be grouped in (a) term inal block(s). Term inal blocks shall have adequate
insulating properties and m echanical strength. I n order to satisfy such requirem ents when
choosing insulating m aterials for the terminal block(s), adequate testing of m aterials shall be
taken into account. See also 9. 3. 2. 1 .
Co n form ity is ch e cke d with th e te st s p e cifie d in 1 0. 5. 2.
The holes in the insulating m aterial which form an extension of the terminal holes shall be of
sufficient size to also accomm odate the insulation of the conductors.
Co n form ity is ch e cke d b y in s p e ctio n .
6. 9. 6
I n s u l ati n g
m a t e ri a l s o f s u p p l y c o n t ro l
an d
l oad
s wi tch e s
I nsulating parts holding current carrying parts of suppl y control and load control switches shall
have adequate insulating properties and mechanical strength. I n order to satisfy such
requirements when choosing insulating materials for the switches adequate testing of
m aterials shall be taken into account.
Co n form ity is ch e cke d with th e te st s p e cifie d in 1 0. 5. 2.
– 90 –
6.9.7
I EC 62052-31 :201 5 © I EC 201 5
Terminals
NOTE This subcl ause 6. 9. 7 is based on I EC 61 01 0-1 : 201 0, 6. 6. 4 an d I EC 62477-1 : 201 2, 4. 1 1 . 8.
6.9.7.1
General requirements
All parts of term inals which maintain electrical contact and carry current shall be made of
metal having adequate m echanical strength.
All metal parts of each terminal shall be such that the risk of corrosion resulting from contact
with an y other metal part is m inim ized.
Term inals shall be anchored, fitted or designed so that conductors will not work loose when
they are tightened, loosened or when connections are m ade.
The terminals, the conductor fixing screws, or the external or internal conductors shall not be
liable to come into contact with terminal covers made of conducting m aterial.
Co n form ity is ch e cke d b y m a n ua l te s t a n d in sp e ction .
The terminals of current circuits of direct connected meters shall be considered to be at the
sam e potential as the related voltage circuit.
NOTE 1 The term inals of current circuits of current transform er operated m eters are gen erally earthed.
Term inals of one current circuit shall be considered to be at the sam e potential.
Term inals which are grouped close together shall be protected against accidental sh ortcircuiting that m ay be detrimental to the operation of equipment and the insulation shall not be
reduced below the rated values, even if a strand of a conductor escapes from a term inal.
Protection may be obtained by insulating barriers.
Co n form ity is ch e cke d b y in s p e ctio n a n d – in ca se o f doub t – b y p e rform in g th e fo llo win g te st:
NOTE 2 The followin g test is from I EC 60950-1 : 2005, 3. 3. 8.
A p ie ce o f in sula tio n a p p roxim a te ly 8 m m lo n g is re m ove d fro m th e e n d of a fle xib le co n ducto r
h a vin g th e
a p p ro p ria te
n om in a l cross -s e ctio n a l a re a .
One
wire
of th e stra n de d co n ductor is
le ft fre e a n d th e oth e r wire s a re fully in s e rte d in to , a n d cla m p e d in th e te rm in a l.
With out
te a rin g
th e
in s ula tion
b a ck,
th e
fre e
wire
is
ben t
in
e ve ry
p ossib le
dire ctio n ,
b ut
with o ut m a kin g s h a rp b e n ds a ro un d th e gua rd.
If th e con ductor is a t h a za rdo us vo lta ge , th e fre e wire sh a ll n o t to uch a n y con ductive p a rt th a t
is
a cce ss ib le
o r is
co n n e cte d
in sula te d e quip m e n t,
to
an
a cce ss ib le
co n ductive
p a rt
or,
in
th e
ca s e
of doub le
a n y con ductive p a rt th a t is se p a ra te d from a cce ssib le co n ductive p a rts
b y s up p le m e n ta ry in s ula tion o n ly.
If th e con ductor is co n n e cte d to a n e a rth in g te rm in a l, th e fre e wire sh a ll n ot to uch a n y p a rt a t
h a za rdous vo lta ge .
6.9.7.2
Connecting capacity
NOTE 1 This subcl ause is based on I EC 62477-1 : 201 2, 4. 1 1 . 8. 2.
Term inals shall be capable to accom modate the conductors specified in the installation and
maintenance manuals in accordance with the wiring rules applicable at the installation.
I EC 62052-31 :201 5 © I EC 201 5
– 91 –
NOTE 2 Stand ard cross-secti ons are specified in Table 1 .
The tem perature of the term inals shall meet the requirem ents of 1 0. 2.
Co m p lia n ce is ch e cke d b y in s p e ctio n .
6. 9. 7. 3
Reli abi l i ty of screw-type con n ecti on s
The m anner of fixing the conductors to the terminals shall ensure adequate and durable
contact such that there is no risk of loosening or undue heating.
Electrical connections shall be designed in a way that contact pressure is not transm itted
through insulating material.
Screw connections transmitting contact force and screw fixings that m ay be loosened and
tightened several tim es during the life of the m eter shall screw into a metal nut.
Th e re lia b ility o f th e con n e ctio n sh a ll b e ch e cke d with th e fo llo win g te s t (fle xio n te s t a n d p ull
te s t) :
NOTE
Th e
This test has been ad opted from I EC 60947-1 : 2007, 8. 2. 4. 3.
te st
curre n t
a p p lie s
to
tra n sform e r
con n e ction
of
m a in s
te rm in a ls
o p e ra te d
ro un d
m e te rs
cop p e r
of dire ct
and
co n ductors ,
to
con n e cte d
te rm in a ls
of
m e te rs ,
of
loa d
cross-se ction
th e
curre n t
co n tro l
and
typ e
te rm in a ls
of
switch e s ,
for
th e
sp e cifie d
by
th e
ma n ufa cture r, a n d p re p a re d a s s p e cifie d b y th e m a n ufa cture r.
Te st
m e th ods
fo r a lum in ium
con ductors
may
be
m a de
a gre e d
b e twe e n
m a n ufa cture r a n d
use r.
Th e te s t is to b e ca rrie d o ut with s uita b le te st e quip m e n t, s e e A n n e x H.
Th e te st sh a ll b e p e rform e d o n a t le a st two te rm in a ls,
us in g b o th th e co n ductor of m in im um
a n d m a xim um cross se ction sp e cifie d b y th e m a n ufa cture r.
Th e con ducto r sh a ll b e
co n n e cte d to th e
te rm in a l te s te d.
Th e
le n gth
o f th e
te st co n ducto rs
sh o uld b e 75 m m lo n ge r th a n th e h e igh t H sp e cifie d in Ta b le H. 1 . Th e cla m p in g scre ws s h a ll
b e tigh te n e d with a torq ue sp e cifie d b y th e m a n ufa cture r.
Th e co n ducto r is s ub je cte d to circula r m o tion s a ccordin g to th e fo llo win g p roce dure :
•
th e e n d o f th e co n ductor un de r te st sh a ll b e p a sse d th ro ugh a n a p p ro p ria te size b ush in g in
a p la te n p ositio n e d a t a h e igh t H b e lo w th e e quip m e n t te rm in a l, a s give n in Ta b le H. 1 . Th e
b ush in g sh a ll b e p ositio n e d in th e h orizo n ta l p la te n co n ce n tric with th e co n ductor;
•
th e
b us h in g s h a ll b e
a b o ut its
ce n tre
in
m o ve d so
th e
th a t its ce n tre lin e de scrib e s
h orizo n ta l p la n e
at 1 0
rp m
±
2
a
rp m .
circle
Th e
o f 75 m m
dista n ce
dia m e te r
b e twe e n
th e
m o uth o f th e te rm in a l a n d th e up p e r surfa ce of th e b ush in g sh a ll b e with in 1 5 m m o f th e
h e igh t
H
in
Ta b le
H. 1 .
Th e
b ush in g
rota tio n of th e in s ula te d con ductor.
is
to
be
lub rica te d
to
p re ve n t
A m a ss a s s p e cified in Ta b le H. 1
b in din g,
twistin g
or
is to b e sus p e n de d
fro m th e e n d o f th e co n ductor. Th e te s t sh a ll co n sist of 1 35 con tin uous re vo lutio n s.
Durin g
th e
te st,
th e
co n ductor
sh a ll
n e ith e r
s lip
o ut
of th e
te rm in a l
n or
b re a k
n ear
th e
cla m p in g un it.
Im m e dia te ly fo llo win g th e fle xio n te st, th e p ullin g force give n in Ta b le H. 1 sh a ll b e a p p lie d to
th e co n ductor. Th e cla m p in g scre ws s h a ll n o t b e tigh te n e d a ga in for th is te s t.
Th e force sh a ll b e a p p lie d with o ut je rks for 1 m in , in th e dire ction of th e a xis o f th e co n ducto r.
– 92 –
I EC 62052-31 :201 5 © I EC 201 5
Durin g th e te s t, th e co n ducto r s h a ll n e ith e r slip o ut o f th e te rm in a l n or b re a k n e a r th e te rm in a l.
6.9.8
6.9.8.1
Requirements for current circuits
Overview
This subclause 6. 9. 8 specifies requirements for:
a) current circuits of direct connected m eters without suppl y control switches (SCSs), see
6. 9. 8.3;
b) current circuits of direct connected meters equipped with suppl y control switches (SCSs)
see 6. 9. 8. 4;
c) m eters and tariff- and load control equipment equipped with load control switches (LCSs),
see 6. 9. 8. 5.
For exam ples of direct connected meters equipped with the various kinds of switches, see
Annex C.
There are no specific safety requirements for auxiliary control switches. Clause 1 3
nevertheless applies.
For functional and performance requirem ents for switches, see the relevant standard.
NOTE At the tim e of the publ ication of this stand ard, these are I EC 62052-1 1 : 2003, I EC 62054-1 1 : 2004,
I EC 62054-21 : 2004 and I EC 62055-31 : 2005.
6.9.8.2
6.9.8.2.1
Characteristics
General
NOTE The characteristics in 6. 9. 8. 2 are based on I EC 60947-1 : 2007, Cl ause 4.
The characteristics specified in this subclause 6. 9. 8. 2 appl y to the metering equipm ent as a
com plete unit, not to the suppl y or load control switch as a component.
6.9.8.2.2
Rated operational voltage ( Ue )
The rated operational voltage of a switch is a value of voltage which, combined with a rated
operational current, determines the application of the switch and to which the relevant tests
and the utilization categories are referred.
Unless a different value is marked, the rated operational voltage Ue of a switch is equal to the
reference voltage of the meter. I n the case of meters with several reference voltages, the
rated operational voltage is equal to the highest reference voltage.
6.9.8.2.3
Rated operational current ( Ie )
The rated operational current of a switch is stated by the m anufacturer an d takes into account
the rated operation voltage, the rated frequency, the rated duty and the utilization category.
For suppl y control switches, the rated operational current is the maximum current Im ax of the
m eter.
For load control switches, the rated operational current shall be m arked. See also Table 22
and Table 23.
6.9.8.2.4
Rated frequency
The suppl y frequency for which the switch is designed and to which the other characteristic
values correspond.
I EC 62052-31 :201 5 © I EC 201 5
6. 9. 8.2.5
– 93 –
Rated u n i n terru pted cu rren t ( Iu )
The rated uninterrupted current of a switch is a value of current, which the equipment can
carry in uninterrupted duty.
6. 9. 8. 2.6
U n in terru pted du ty
A duty without an y off-load period in which the main contacts of an equipm ent remain closed,
whilst carrying a stead y current without interruption for periods of more than 8 h (weeks,
months, or even years).
I n this kind of service oxides and dirt can accumulate on the contacts and lead to progressive
heating. U ninterrupted duty m ay require special design considerations (e. g. silver contacts).
6. 9. 8. 2.7
Rated m akin g capacity ( Im )
The rated m aking capacity of a switch is a value of current which the switch can satisfactoril y
m ake under specified making conditions.
The making conditions which shall be specified are:
•
•
the applied voltage;
the characteristics of the test circuit.
The rated m aking capacity is stated by reference to the rated operational voltage and rated
operational current.
For a.c., the rated making capacity is expressed by the r. m. s. value of the sym metrical
com ponent of the current, assumed to be constant.
NOTE For a. c. , the peak val u e of the current d uri ng the fi rst half-cycl es followi ng th e closing of the m ain contacts
m ay be appreciabl y g reater than th e peak val ue of th e current un der stead y-state conditi ons used in th e
determ ination of m aking capacity, d ependi ng on the power factor of th e circuit and th e i nstant on the voltag e wave
when closing occurs.
6. 9. 8. 2.8
Rated breaki n g capacity ( Ic )
The rated breaking capacity of a switch is a value of current, which the equipment can
satisfactoril y break, under specified breaking conditions.
The breaking conditions which shall be specified are:
•
•
the applied voltage;
the characteristics of the test circuit.
The rated breaking capacity is stated by reference to the rated operational voltage and rated
operational current.
Equipm ent shall be capable of breaking an y value of current up to and including its rated
breaking capacity.
For a.c., the rated breaking capacity is expressed by the r.m .s. value of the symm etrical
com ponent of the current.
6. 9. 8. 2.9
Rated safe sh ort-tim e wi th stan d cu rren t ( Issw )
The rated safe short-time withstand current is the value of current that the current circuit of a
direct connected m eter and – if fitted – the suppl y control switch can withstand withut damage
under the test conditions specified.
– 94 –
6.9.8.2.1 0
I EC 62052-31 :201 5 © I EC 201 5
Rated operational short-time withstand current ( Iosw )
The rated operational short-time withstand current is the value of current that the current
circuit of a direct connected meter and – if fitted – the suppl y control can withstand without
dam age and the SCS remaining operational, under the test conditions specified.
6.9.8.2.1 1
Rated short-circuit making capacity ( Ism )
The rated short-circuit making capacity of a switch is the value of short-circuit making
capacity for the rated operational voltage, at rated frequency, and at a specified power-factor
for a.c. lt is expressed as the m aximum prospective peak current, under prescribed
conditions.
6.9.8.2.1 2
Rated conditional safe short-circuit current ( Icssw )
The rated conditional safe short-circuit current of the switch is the value of prospective current
which the switch, protected by a short-circuit protective device specified , can withstand for the
operating tim e of this short-circuit protective device and the switch remaining safe but not
necessaril y operational, under the test conditions specified.
NOTE For a. c. , the rated conditi on al safe sh ort-circuit current is expressed by th e r. m . s. value of the a. c.
com ponent.
6.9.8.2.1 3
Rated conditional operational short-circuit current ( Icosw )
The rated conditional operational short-circuit current of the switch is the value of prospective
current which the switch, protected by a short-circuit protective device specified, can
withstand without dam age for the operating time of this short-circuit protective device and the
switch rem aining operational under the test conditions specified.
NOTE For a. c. , the rated con dition al operational sh ort-circu it current is expressed by the r. m . s. value of the a. c.
com ponent.
6.9.8.3
Current circuits of direct connected meters without SCS
The requirements for current circuits of direct connected m eters without SCS are summ arized
in Table 21 .
I EC 62052-31 :201 5 © I EC 201 5
– 95 –
Table 21 – Summary of requirements for current circuits
of direct connected meters without SCS
Requirement
UC1
Value
Utilization category a
UC2
UC3
UC4
1
Rated operation al voltage ( Ue )
Equal to th e reference voltag e of the m eter b
2
Rated frequency
Equal to the reference freq uen cy of the m eter
3
Rated operation al current Ie , equal to the m axim um
current Ima x of the m eter, c
4
Duty
5
Rated uni nterrupted current ( Iu ) at 1 , 1 5
6
Endu rance / Num ber of operati ng cycles
7
Surg e voltag e withstand across open contacts
N. A.
8
Rated m aking capacity ( Im ) at 1 , 1 5
N. A.
9
Rated breakin g capacity ( Ic ) at 1 , 1 5
10
≤ 1 25 A
≤ 200 A
N. A.
Maxim um overl oad current
at 1 , 1 5
≤ 1 00 A
Ue ,
Ue ,
Equal to
Ue
d
Ie
N. A.
cos φ = 1
N. A.
cos φ = 1
As agreed between th e m anufacturer an d the
purch aser
Iovl
Rated safe short-tim e withstand current ( Issw )
11
≤ 63 A
e
3 000 A
Ue
4 500 A
6 000 A
1 0 000 A
Fo r de ta ile d re q uire me n ts a n d te st me th o ds s e e 6. 1 0. 6. 6.
12
13
14
Rated operation al short-tim e withstand cu rrent ( Iosw )
at 1 , 1 5
Ue
Rated short-circuit m aking capacity ( Ism )
at 1 , 1 5
d
d
N. A.
Ue
Neutral switchi ng (Opti on al)
For m eters with
purch aser.
Ima x
N. A.
N. A.
above 200 A the valu es of test currents shall be ag reed between th e manufacturer and th e
a)
The utili zation category is subject to th e purch ase agreem en t between th e supplier an d th e purch aser. For
m arking, see 5. 3. 5.
b)
I f the m eter has several reference voltag es, then
Ue
is equ al the hi ghest reference voltag e of the m eter.
c)
Values of rated operating cu rrent have been taken from I EC 60898-1 : 201 5, 5. 3. 2, except the 200 A valu e.
d)
Values for sh ort-tim e withstan d current h ave been taken from I EC 60898-1 : 201 5, 5. 3. 4, except the 2 500 A
val ue. For power factor see Table 27.
NOTE For coherence, th e structure of this tabl e is th e sam e as that of Tabl e 22.
Co m p lia n ce to th e re q uire m e n ts o f Ta b le 21 is ve rifie d b y th e te sts sp e cifie d in 6. 1 0. 5.
– 96 –
6.9.8.4
I EC 62052-31 :201 5 © I EC 201 5
Current circuits of direct connected meters with SCS
The requirements for suppl y control switches are summarized in Table 22.
Table 22 – Summary of requirements for current circuits
of direct connected meters with SCS
Value
Utilization category a
UC2
UC3
Requirement
UC1
UC4
1
Rated operation al voltage ( Ue )
Equal to th e reference voltag e of the m eter b
2
Rated frequency
Equal to the reference freq uen cy of the m eter
3
Rated operation al current Ie , equal to the m axim um
current Ima x of the m eter, c
4
Duty
5
Rated uni nterrupted current ( Iu ) at 1 , 1 5
6
≤ 63 A
≤ 1 00 A
≤ 1 25 A
≤ 200 A
Uninterru pted duty
Equal to
Ue
5 000 at Ue ,
d
Endu rance / Num ber of operati ng cycles
Ie ,
5 000 at Ue ,
Ie
cos φ = 1
Ie ,
an d then
cos φ = 0, 5 ind
perform ed on the sam e switch
Fo r de ta ile d re q uire m e n ts a n d te st m e th o ds s e e 6. 1 0. 6. 4.
7
Surg e voltag e withstand across open contacts
m ax. 1 2 000 V
Fo r de ta ile d re q uire m e n ts a n d te st m e th o ds s e e 6. 1 0. 6. 5.
8
Rated m aking capacity ( Im ) at 1 , 1 5
9
Rated breakin g capacity ( Ic ) at 1 , 1 5
10
Maxim um overl oad current
Ue ,
Ue ,
cos φ = 1
cos φ = 1
at 1 , 1 5
Ie
Equal to
Ie
As agreed between th e m anufacturer an d the
purch aser
Iovl
Rated safe short-tim e withstand current ( Issw )
11
Equal to
e
3 000 A
Ue
4 500 A
6 000 A
1 0 000 A
3 000 A
4 500 A
3 000 A
4 500 A
Fo r de ta ile d re q uire me n ts a n d te st me th o ds s e e 6. 1 0. 6. 6.
Rated operation al short-tim e withstand cu rrent ( Iosw )
12
at 1 , 1 5
Ue
d
1 500 A
2 500 A
.
Fo r de ta ile d re q uire me n ts a n d te s t me th o ds se e 6. 1 0. 6. 7
Rated short-circuit m aking capacity ( Ism )
13
at 1 , 1 5
d
1 500 A
Ue
2 500 A
Fo r de ta ile d re q uire me n ts a n d te st me th o ds s e e 6. 1 0. 6. 8.
14
Neutral switchi ng (Opti on al)
UC equal to U C of ph ase switches.
Fo r de ta ile d re q uire me n ts a n d te st me th o ds s e e 6. 1 0. 6. 3.
For m eters with
purch aser.
Ima x
above 200 A the valu es of test currents shall be ag reed between th e manufacturer and the
a)
The utili zation category is subject to th e purch ase agreem en t between th e supplier an d th e purch aser. For
m arking, see 5. 3. 5.
b)
I f the m eter has several reference voltag es, then
c)
Values of rated operating cu rrent have been taken from I EC 60898-1 : 201 5, 5. 3. 2, except the 200 A valu e.
d)
Ue
is equ al the hi ghest reference voltag e of the m eter.
Valu es for short-tim e withstand current an d short-circuit m aking capacity have been taken from I EC 608981 : 201 5, 5. 3. 4, except the 2 500 A valu e. For power factor see Table 27.
Co m p lia n ce to th e re q uire m e n ts o f Ta b le 22 is ve rifie d b y th e te sts sp e cifie d in 6. 1 0. 6.
I EC 62052-31 :201 5 © I EC 201 5
– 97 –
A direct connected meter may have zero or more suppl y control switches, intended to control
suppl y to the premises. Suppl y control switches shall be able to:
•
•
•
carry, make and break currents up to and including Im ax of the meter;
carry, make and break negligible currents: the starting current of the meter;
carry, m ake and break overload currents;
NOTE
•
This conditi on occu rs occasional ly when the su ppl y side protecti on d oes not trip im m ediately.
carry and make short-circuit currents.
A suppl y control switch may have additional functions like circuit breaker, contactor, isolator,
earth leakage detector, under / over voltage detector and raised neutral detector.
Requirements and tests of such functions are out of the Scope of this standard.
A suppl y control switch shall be designed for uninterrupted duty.
A suppl y control switch is intended for infrequent use: up to 3 operating cycles per day.
The current circuit of the meter, including the suppl y control switch(s) is protected by the
upstream (supply side) protection of the installation.
Suppl y control switches m ay be part not onl y of meters but of other equipm ent constituting the
installation. H owever, this standard applies onl y to suppl y control switches being part of
meters.
6. 9. 8. 5
Load con trol swi tch es
The requirem ents for load control switches are summ arized in Table 23.
Meters, tariff and load control devices may have zero or m ore load control switches. When
built into m eters, load control switches m ay be connected in series with (a) current circuit(s)
or m ay have independent term inals. The rated operational current of a load switch may be
lower than the m aximum current of the m eter. Load control switches shall be able to:
•
•
carry, make and break currents up to their rated operational current Ie ;
carry short circuit currents.
NOTE A load control switch is not intended to provid e isolati on function.
A load control switch shall be designed for uninterrupted duty.
A load control switch is intended for infrequent use: up to 1 operating cycle per hour.
I n all applications, load control switches are protected by the downstream (load side)
protection of the installation.
Short circuits m ay occur on the wires – rated to carry the current of the load control switch(s)
– between the load control switch and the downstream protection, although the probability of
such an event is very low. Such faults are cleared then by the suppl y side protection.
– 98 –
I EC 62052-31 :201 5 © I EC 201 5
Tabl e 23 – Su m m ary of req u i rem en ts for l oad con trol swi tch es
Req u i rem en t
1
Rated operation al voltage ( Ue )
2
Rated frequency
Val u e
Equal to th e reference voltag e of the m eter
or tariff an d load control d evice a
Equal to th e reference frequen cy of the m eter
or tariff an d load control d evice
Rated operation al current Ie , A b at cos φ = 1
3a
3b
Rated operation al current Ie , A
b
at cos φ = 0, 4
4
Duty
5
Rated uni nterrupted current ( Iu )
6
10
16
25
32
40
63
80
1 00
1
5
8
10
10
10
10
10
10
Uninterru pted duty
Equal to
Endu rance / Num ber of operati ng cycles
at Ue ,
2
Ie ,
30 000 on sam ple 1
cos φ = 1
at Ue , red uced
Ie ,
Ie
c
(see above), cos φ = 0, 4
30 000 on sam ple 2
75 000 on sam ple 3
No load
NOTE See also Fi gu re 1 0.
Fo r de ta ile d re q uire m e n ts a n d te st m e th o ds s e e 6. 1 0. 7. 3.
7
8
9
Rated m aking capacity ( Im ) at 1 , 1 5
Ue ,
cos φ = 1
Rated breakin g capacity ( Ic ) at 1 , 1 5
Ue ,
cos φ = 1
Rated conditi on al safe short-ci rcuit current
( Icssw ) c
Equal to
Ie
Equal to
Ie
7 000 A
Fo r de ta ile d re q uire me n ts a n d te s t me th o ds se e 6. 1 0. 7. 4.
10
Rated conditi on al operational short-circuit
current ( Icosw ) c
3 000 A
Fo r de ta ile d re q uire me n ts a n d te s t me th o ds se e 6. 1 0. 7. 5.
a)
For load control switches with i ndepen dent term inals, oth er voltages m ay be specified.
b)
Values of rated operating cu rrent have been taken from I EC 60898-1 : 201 5, 5. 3. 2, except the 2 A value.
Other val ues m ay be ag reed on by th e m anufacturer an d the suppli er.
c)
These valu es are appropri ate for install ations where supply control switch es UC1 to U C3 are appropri ate.
Special considerati on is requi red for sel ection of th e protection device when th e m eter contains a U C4 rated
suppl y control switch. For power factor see Table 27.
Co m p lia n ce to th e re q uire m e n ts o f Ta b le 23 is ve rifie d b y th e te sts sp e cifie d in 6. 1 0. 7.
I EC 62052-31 :201 5 © I EC 201 5
6. 1 0
– 99 –
Safety related el ectrical tests
6. 1 0. 1
Overvi ew
Sa fe ty re la te d e le ctrica l te st p ro ce dure s a re sp e cifie d for:
a)
te stin g o f vo lta ge circuits , se e 6. 1 0. 3;
b)
te s tin g o n die le ctrics on co m p le te e quip m e n t, se e 6. 1 0. 4 . 3;
c)
te s tin g o f die le ctrics o n s ub - a sse m b lie s, se e 6. 1 0. 4. 4;
d)
te s tin g o f curre n t circuits of dire ct co n n e cte d m e te rs with out SCSs, se e 6. 1 0. 5;
e)
te s tin g o f curre n t circuits of dire ct con n e cte d m e te rs with SCSs, s e e 6. 1 0. 6;
f)
te s tin g o f loa d co n tro l s witch e s s e e 6. 1 0. 7.
Un le ss
oth e rwis e
s p e cifie d,
th e
te sts
s p e cifie d
pe rform e d o n n e wly m a n ufa cture d e quip m e n t.
b e low
Sin ce
a p p ly
to
typ e
de te riora tion
te stin g
of th e
and
sh a ll
te st sp e cim e n
be
may
occur, furth e r use o f th e te st sp e cim e n m a y n o t b e a p p ro p ria te .
If for
any
re a so n
th e
im p uls e
vo lta ge
or
pe rform e d o n a n e w sp e cim e n .
Th e te st p roce dure is s h own in Figure 1 0.
surge
te sts
h a ve
to
be
re p e a te d,
th e y
may
be
– 1 00 –
I EC 62052-31 :201 5 © I EC 201 5
IEC
Fi g u re 1 0 – F l owch art of safety rel ated el ectri cal tests
I EC 62052-31 :201 5 © I EC 201 5
6. 1 0. 2
6. 1 0. 2. 1
– 1 01 –
Test m eth od s
At m o s p h e ri c c o n d i t i o n s
Safety related electrical tests shall be made in normal atmospheric conditions of use. See
4. 3. 1. During the test, the quality of the insulation shall not be impaired by dust or abnormal
humidity.
6. 1 0. 2. 2
Test l ead s
The length and the cross-section of the test cable shall be as specified in 4. 3. 2. 11.
6. 1 0. 2. 3
I m pu l s e vol tag e te s t
NOTE 1 This subcl ause is based on I EC 61 1 80-1 : 1 992, 6. 2.
The standard impulse shall be a full impulse having a virtual front time of 1, 2 µ s and a time to
half-value of 50 µ s. It is described as a 1,2 / 50 impulse.
The following differences are accepted between specified values for the standard impulse and
those actually recorded:
•
•
•
peak value ± 3 %;
front time ± 30 %;
time to half-value ± 20 %.
Where high capacitive loading does not allow the impulse waveshape to be obtained within
the specified tolerances, it may be necessary to perform a d.c. voltage test as an alternative
(see 6. 10. 2. 6).
Unless otherwise specified:
•
the conventional output impedance of the generator shall be 500 Ω ± 10 %.
The calibration of the measuring system shall be verified in accordance with the requirements
of IEC 61180-2.
The test voltage shall be as specified in the relevant subclauses.
Unless otherwise specified, the impulse voltage is applied for ten times with one polarity and
then repeated with the other polarity. The minimum time between the impulses shall be 3 s.
The waveshape of each impulse shall be recorded.
It is permissible for an impulse voltage waveform applied across test points connected to
surge suppression devices, inductive devices or potential dividers, to be attenuated or
distorted if this is not due to electrical breakdown.
The waveform applied to test points not connected to such devices, will not be noticeably
distorted or attenuated unless the insulation does not withstand the impulse voltage test.
Pass / fail criteria: Unless otherwise specified, the requirements of the test are satisfied if no
disruptive discharge (sparkover, flashover or puncture) occurs on the test object.
– 1 02 –
6.1 0.2.4
I EC 62052-31 :201 5 © I EC 201 5
Surge test
NOTE 1 This subcl ause is based on I EC 61 000-4-5: 201 4, 6. 1 .
NOTE 2 The surge test specified in this subclause is intended to verify the correct operation of the surge
protective devices (SPDs) inside the product for safety purposes and it is not to be considered as an EMC test.
The generator is intended to generate a surge having:
•
•
•
•
an open-circuit voltage front time of 1, 2 µ s;
an open-circuit voltage duration of 50 µ s;
a short-circuit current front time of 8 µ s; and
a short-circuit current time duration of 20 µ s.
For convenience, the ratio of peak open-circuit output voltage to peak short-circuit current of a
combination wave generator may be considered the effective output impedance. For this
generator, the ratio defines an effective output impedance of 2 Ω .
The waveform of the voltage and current is a function of the EUT input impedance. This
impedance may change during surges to equipment due either to proper operation of the
installed protection devices, or to flash over or component breakdown if the protection devices
are absent or inoperative. Therefore, the 1, 2/50 µs voltage and the 8/20 µ s current waves
have to be available from the same generator output as required by the load.
Characteristics and performance of the generator:
•
•
Open-circuit voltage:
– Front time: 1,2 µ s ± 30 %;
– Time to half value: 50 µ s ± 20 %.
– Peak voltage tolerance: ± 10 %.
Short-circuit current:
– Front time: 8 µ s ± 20 %;
– Time to half value 20 µ s ± 20 %;
– Peak current tolerance: ± 10 %.
The test voltage may be applied with – using suitable coupling/decoupling networks – or
without mains as specified in the relevant clauses (6. 10. 3. 4 and 6. 10. 6. 5).
The test levels, the polarity and the position of the surges relative to the mains voltage, the
number and the repetition rate of the surges shall be as specified in the relevant clauses.
Pass / fail criteria: as specified in the relevant clauses.
6.1 0.2.5
AC power-frequency voltage test
NOTE 1 The followin g is based on I EC 61 1 80-1 : 1 992, 5. 2.
The alternating test voltage, as applied to the test object, shall have a frequency in the range
45 Hz to 65 Hz, normally referred to as power-frequency test voltage.
The voltage shape shall approximate to a sinusoid with both half-cycles closely alike. This
5 %.
requirement is considered met if the ratio of peak to r. m. s. values is equal to √2 ±
The test voltage shall be as specified in the relevant clauses. A tolerance of ± 3 % is
acceptable between the specified and the measured test voltage values when connected to
the EUT.
I EC 62052-31 :201 5 © I EC 201 5
– 1 03 –
The voltage in the test circuit should be stable enough to be practically unaffected by varying
leakage currents.
At the test voltage, the prospective short-circuit current at the test object shall be at least
200 mA r. m.s.
For test voltages exceeding 3 000 V, it is sufficient that the rated power of the test equipment
is equal to or greater than 600 VA.
If capacitors with high capacitance are parallel to the parts between which the test voltage
needs to be applied, it may be difficult, or even impossible, to perform the a.c. voltage test
because the charging current would exceed the capacity of the high voltage tester (200 mA).
In the latter case, those parallel capacitors should be disconnected before testing. If this is
also impossible, d.c. voltage testing can be taken into consideration (see 6. 10. 2. 6).
The characteristics of the generator shall be verified in accordance with the requirements of
IEC 61180-2.
The tripping current of the generator shall be adjusted to a tripping current of 10 mA or for
test voltages above 6 000 V to the highest possible value.
NOTE 2 The tripping current is calculated from the leakage current multiplied by 2 times the ratio between the
test voltage and the nominal voltage. The leakage current is specified in 6. 3. 2.
EXAMPLE For a meter with Un = 230 V, when the test is made at 2 0 00 V, then the tripping current shall be set to
2* 0, 5 mA * 2 000 / 230 = 8, 6 mA — > 10 mA. When the test is made at 4 000 V, then the tripping current shall be
set to 20 mA.
If the generator trips, it is not necessarily due to an insulation failure. The root-cause of the
tripping shall be investigated.
The voltage shall be applied to the test object starting at a value sufficiently low to prevent
any effect of overvoltages due to switching transients. It shall be raised sufficiently slowly as
to permit accurate reading of the measuring instrument but not so slowly as to cause
unnecessary prolongation of the stressing of the test object near to the test voltage.
These requirements are, in general, met if the rate of the rise is about 5 % of the estimated
final test voltage per second, when the applied voltage is above 75 % of this voltage. It shall
be maintained for the specified time and then rapidly decreased, but not suddenly interrupted,
as this may generate switching transients which could cause damage or erratic test results.
The test duration shall be as specified in the relevant clauses and should be independent of
the frequency in the range from 45 Hz to 65 Hz.
Pass / fail criteria: Unless otherwise specified, the requirements of the test are satisfied if no
disruptive discharge (sparkover, flashover or puncture) occurs on the test object.
6.1 0.2.6
DC voltage test
NOTE The fol lowing is based on I EC 61 1 80-1 : 1 992, 4. 2.
The test voltage, as applied to the test object, shall be a direct voltage with not more than 3 %
ripple factor. Note that the ripple factor may be affected by the presence of the test object and
by the test conditions.
The test voltage shall be as specified in the relevant clauses. A tolerance of ± 3 % is
acceptable between the specified and the measured test voltage values when connected to
the EUT.
– 1 04 –
I EC 62052-31 :201 5 © I EC 201 5
The characteristics of the test voltage source and the calibration of the measuring system
shall be verified in accordance with the requirements of IEC 61180-2.
The voltage shall be applied to the test object starting at a value sufficiently low to prevent
any effect of overvoltage due to switching transients. It should be raised sufficiently slowly as
to permit reading of the instruments, but not so slowly as to cause unnecessary prolongation
of stressing of the test object near to the test voltage. These requirements are, in general,
met if the rate of rise is about 5 % of the estimated final voltage per second when the applied
voltage is above 75 % of this voltage. It shall be maintained for the specified time and then
reduced by discharging the smoothing capacitor and the test object through a suitable
resistor.
The test duration shall be as specified in the relevant clauses taking into consideration that
the time to reach the steady state voltage distribution depends on the resistances and
capacitances of the test object components.
Unless otherwise specified, the requirements of the test are satisfied if no disruptive
discharge (sparkover, flashover or puncture) occurs on the test object.
6.1 0.2.7
Altitude correction for testing clearances
NOTE This subcl ause is from I EC 61 01 0-1 : 201 0, 6. 8. 1 .
When verifying clearances, the values for test voltages given in 6. 7 appl y to tests perform ed
at 2 000 m . For other test site altitudes, the corrections of Table 24 are applied for clearances
but not for tests of solid insulation.
Table 24 – Correction factors according to test site altitude
for test voltages for clearances
Correction factors
Test voltage
peak
Test voltage
r. m. s.
≥ 327
V < 600 V
≥ 600
V < 3 500 V
≥ 231
V < 424 V
≥ 424
V < 2 475 V
≥3
≥2
500 V < 25 kV
≥ 25
kV
475 V < 1 7,7 kV
≥ 1 7,7
kV
Test site alti tude
m
0
1 , 08
1 ,1 6
1 , 22
1 , 24
500
1 , 06
1 ,1 2
1 ,1 6
1 ,1 7
1 000
1 , 04
1 , 08
1 ,1 1
1 ,1 2
2 000
1 , 00
1 , 00
1 , 00
1 , 00
3 000
0, 96
0, 92
0, 89
0, 88
4 000
0, 92
0, 85
0, 80
0, 79
5 000
0, 88
0, 78
0, 71
0, 70
Linear i nterpolation is allowed.
6.1 0.3 Testing of voltage circuits
6.1 0.3.1
Overview
Testing of voltage circuits com prises four tests:
a)
b)
c)
d)
testing of long term overvoltage withstand, see 6.1 0. 3. 2;
im pulse voltage test without suppl y voltage – see 6. 1 0. 3. 3 – and depending on the result:
surge test, superimposed on suppl y voltage, see 6.1 0. 3.4; and
im pulse voltage test without suppl y voltage, one step lower, see 6. 1 0. 3. 5.
I EC 62052-31 :201 5 © I EC 201 5
6. 1 0. 3. 2
Lon g
t e rm
– 1 05 –
o v e rv o l t a g e w i t h s t a n d
Meters and tariff and load control equipment shall withstand the maximum withstand voltage,
1, 9 Un applied as follows:
NOTE
•
•
•
•
•
•
Un is the n om inal voltage between a li ne and the n eutral.
for single-phase two-wire meters, the maximum withstand voltage shall be applied
between the line and neutral terminals;
for single-phase two-wire multi-element meters the maximum withstand voltage shall be
applied on all the elements simultaneously, between the line and neutral terminals;
for three-phase four-wire polyphase types, the maximum withstand voltage shall be
applied to any two phases and neutral with a phase angle of 60° between the two phase
voltages. A total of three test runs is required to cover the pairs of phases, with a cooling
period of 1 h between each run;
for three-phase three-wire meters this requirement does not apply.
when the current circuit (of a direct connected meter) contains supply control switches,
then these switches shall be in the open position and the load side terminals shall be
connected so that the maximum test voltage appears across the open supply control
switch;
for tariff-and load control equipment, the maximum withstand voltage shall be applied
between the line and neutral terminals.
The test circuit diagram is shown in Annex D.
In every configuration (test run) described above, the maximum withstand voltage of 1, 9 Un
shall be applied for 4 h, with a cooling period of 1 h between the test runs.
During the test, the EUT may be damaged, but no hazardous live parts shall be exposed, no
fire shall occur, or if it occurs, it shall be contained in the meter. When more than one test run
is required, all of them have to be passed.
6. 1 0. 3. 3
I m p u l s e vo l ta g e t e s t wi th o u t s u p p l y vo l ta g e
This test does not have to be carried out if it can be ascertained from the circuit diagram that
SPDs are present in the voltage circuit. In that case the tests specified in 6. 10. 3. 4 and
6. 10. 3. 5 have to be performed.
The impulse voltage test specified in 6.10. 2.3 shall be applied:
a) to voltage circuit(s):
1) When the voltage and the current circuits of a measuring element are connected
together in normal use (for example direct connected meters) the test shall be made
on the whole measuring element. The impulse voltage shall be applied between this
common point and earth, with the other terminal of the voltage circuit connected to the
earth and the other end of the current circuit left open. If there is a supply control
switch present, then it shall be closed. All other terminals shall be connected to earth.
When the meter has several measuring elements the impulse voltage shall be applied
to each measuring element one by one.
2) When the voltage and the current circuits of a measuring element are separated and
appropriately insulated in normal use (for example transformer operated meters) the
test shall be made on the voltage circuit only. The impulse voltage shall be applied
between one terminal of the voltage circuit and earth, with the other terminal of the
voltage circuit and all other terminals connected to earth. When the meter has several
measuring elements the impulse voltage shall be applied to each voltage circuit one
by one.
b) to auxiliary supply circuit(s) with a reference voltage above 33 V a.c. or 70 V d.c. between
the supply terminals.
– 1 06 –
I EC 62052-31 :201 5 © I EC 201 5
The test voltage shall be as specified in Table 7 for basic insulation. For examples of test
arrangements see Annex F.
If during the test the impulse voltage is not clamped and the other pass / fail criteria of
6. 10. 2. 3 are met, the test is passed.
If the impulse voltage is clamped – that is the test voltage is reduced by more than 15 % –
then the tests specified in 6. 10. 3. 4 and 6. 10. 3. 5 have to be performed as well.
6. 1 0 . 3. 4
S u rg e t e s t w i t h
s u p p l y vo l ta g e
The surge test specified in 6. 10. 2. 4 shall be applied as follows:
•
•
•
•
•
•
this test shall be carried out with a supply side overcurrent protection present in each
phase to protect the coupling network. The characteristics of the protection shall be
agreed between the manufacturer and the purchaser and shall be included in the test
report;
the surges shall be applied to the same points as specified in 6.10. 3.3;
the test voltage shall be as specified in Table 7 for basic insulation;
5 positive and 5 negative surges shall be applied;
the surges shall be superimposed on the peak of the sine wave;
the waveshape shall be recorded.
The requirements of the test are satisfied if no disruptive discharge (sparkover, flashover or
puncture) occurs on the test object and no SPD failure occurs.
If the surge voltage is still clamped, then the manufacturer and the test house shall agree if
further tests are required.
6. 1 0 . 3. 5
I m p u l s e vo l tag e te s t wi th
S P D s n o t p re s e n t
In the case where surge protective devices (SPDs) are used inside a meter to reduce the
overvoltage levels below the rated impulse voltage values specified in Table 7, the impulse
voltage test shall be also performed on a specially prepared sample with SPDs removed.
The test shall be performed as specified in 6. 10. 3. 3, but the value of the impulse test voltage
shall be one step lower, as specified in 6.7. 6.
NOTE The purpose of this test is to verify that clearances meet the requirements for reduced impulse voltages.
The pass / fail criteria of 6. 10. 2. 3 apply.
6. 1 0. 4
6. 1 0 . 4. 1
D i e l e c t ri c t e s t s
T e s ti n g
co m p l e te e q u i p m e n t vs . s u b -a s s e m b l i e s
Dielectric tests on complete equipment is the preferred method.
NOTE 1 The reason for this is that with some designs, metering equipment is sealed for life and all parts of the
meter case eventually have functions in fulfilling the requirements for clearances and creepage distances.
NOTE 2 Verification of clearances and creepage distances by measurement as specified in 6. 7 is performed on
disassembled metering equipment.
In some designs, applying test voltages for double or reinforced insulation between mains
circuits and PELV / SELV circuits may overstress certain insulations or circuits that are not
required to withstand these voltages, or some sensitive components may be damaged. In
such cases insulation tests shall be carried out on sub-assemblies. See explanations to the
figures in Annex B.
I EC 62052-31 :201 5 © I EC 201 5
6. 1 0. 4. 2
– 1 07 –
H u m id ity precon d iti on i n g
NOTE The fol lowing is based on I EC 61 01 0-1 : 201 0, 6. 8. 2.
The equipment is subjected to humidity preconditioning before the dielectric tests. The
equipment is not energized during preconditioning.
When testing sub-assemblies, this treatment need not be applied to parts that are clearly
unlikely to be influenced by humidity and temperature.
Preconditioning is carried out as specified in IEC 60068-2-78, in a humidity chamber
containing air with a humidity of (93 ± 3) % RH. The temperature of the air in the chamber is
maintained at (40 ± 2) °C.
Before applying humidity, the equipment is brought to a temperature of 40 °C ± 2 °C, normally
by keeping it at this temperature for at least 4 h before the humidity preconditioning.
The air in the chamber is stirred and the chamber is designed so that condensation will not
precipitate on the equipment.
The equipment remains in the chamber for 48 h, after which it is removed and allowed a
recovery period of 2 h under the environmental conditions of 4. 3. 1, with the covers of nonventilated equipment removed if this is possible.
The tests are performed and completed within 1 h of the end of the recovery period after
humidity preconditioning.
6. 1 0. 4. 3
6. 1 0. 4. 3. 1
Di el ectri c test on com pl ete equ i pm en t
Test meth od s
This subclause specifies test methods for testing complete equipment using:
a) impulse voltage test specified in 6. 10. 4. 3. 3; and
b) a.c. power-frequency voltage test specified in 6. 10.4.3. 4.
The impulse voltage test shall be performed first, followed by the a.c. voltage test.
The results of the insulation tests are considered to be valid only for the terminal arrangement
of the metering equipment, which has undergone the tests. When the terminal arrangements
differ, all the insulation tests shall be carried out for each arrangement.
6. 1 0. 4. 3. 2
Preparati on of th e m eteri n g equ ipmen t for testi n g
NOTE This subcl ause is based on I EC 62052-1 1 : 2003, 7. 3. 1 .
Unless otherwise specified, the tests shall be carried out on complete metering equipment,
with its cover (except when indicated otherwise) and terminal cover in place, the terminal
screws being screwed down to touch the conductors of the maximum size that can be
accommodated by the terminals.
To create a continuous circuit for the voltage tests, terminals and open contacts of switches
shall be bridged where necessary. Before testing, semiconductor devices and other
vulnerable components within a circuit may be disconnected and/or their terminals bridged to
avoid damage occurring to them during the test. The modifications to be performed shall be
agreed on by the manufacturer and the test laboratory and shall be documented in the test
report.
For the purpose of these tests, the term ”earth” has the following meaning:
– 1 08 –
a)
I EC 62052-31 :201 5 © I EC 201 5
wh e n th e ca se o f th e m e te rin g e quip m e n t is m a de o f m e ta l,
th e “e a rth ” is th e ca s e its e lf,
p la ce d o n a fla t con ductin g s urfa ce ;
b)
wh e n th e
m e te r ca se or on ly a
con ductive
p a rt of it is m a de o f in s ula tin g m a te ria l,
fo il wra p p e d a ro un d th e
m e te r to uch in g
a ll a cce ss ib le
th e “e a rth ” is a
co n ductive
p a rts
and
con n e cte d to th e fla t con ductin g surfa ce o n wh ich th e m e te r b a s e is p la ce d.
A
ga p
of 2 cm
sh a ll b e
le ft b e twe e n
th e
e a rth
a n d th e
te rm in a ls
to
a vo id fla s h o ve r to
th e
co n n e cte d to ge th e r a n d to
th e
te rm in a ls.
Durin g
th e
te s ts,
circuits
wh ich
a re
n ot un de r te st sh a ll b e
e a rth .
For p a ym e n t m e te rs,
th e
fo llowin g s p e cia l con dition s a p p ly: Wh e re
a
p h ysica l toke n
ca rrie r
a cce p tor is fitte d, th e m e te r sh a ll with sta n d th e te sts with a m e ta llic toke n in th e toke n ca rrie r
a cce p tor or,
if th e m e ta llic toke n ca n n o t b e re ta in e d,
th e p h ys ica l to ke n ca rrie r in te rfa ce .
with a suita b le e le ctrica l co n n e ctio n to
Such m e ta llic toke n s or e le ctrica l co n n e ctio n s sh a ll th e n
b e con n e cte d to th e e a rth for th e p urp os e s of th e se te s ts.
6.1 0.4.3.3
The impulse voltage test
Th e im p ulse vo lta ge te st m e th o d sp e cifie d in 6. 1 0. 2. 3 is use d.
Th e a ltitude corre ction fa cto rs sp e cifie d in 6. 1 0. 2. 7 a p p ly.
Th e te s t vo lta ge sh a ll b e a p p lie d:
a)
b e twe e n a ll th e HL V te rm in a ls co n n e cte d toge th e r a n d e a rth . Th e te st vo lta ge s h a ll b e a s
sp e cifie d
in
m e te rin g
e q uip m e n t
Ta b le
7,
ta ke n
of
fro m
th e
p ro te ctive
co lum n
cla ss
I
“B a s ic
and
th e
and
sup p le m e n ta ry
co lum n
“Re in force d
in s ula tio n ” for
in sula tion ”
for
m e te rin g e quip m e n t of p rote ctive cla ss II.
b)
b e twe e n e a ch in de p e n de n t (gro up o f) HL V circuit(s) . Th e te st vo lta ge sh a ll b e a s s p e cifie d
in Ta b le 7, ta ke n fro m th e co lum n “B a sic a n d sup p le m e n ta ry in sula tio n ”. Wh e n te stin g th e
curre n t circuits o f tra n sform e r o p e ra te d m e te rs,
th e te s t vo lta ge sh a ll b e se le cte d b a s e d
on th e n om in a l volta ge o f th e corre s p on din g vo lta ge circuit.
For e xa m p le s o f te s t a rra n ge m e n ts se e A n n e x F.
6.1 0.4.3.4
The AC power-frequency voltage test
NOTE This subclause is based on I EC 60060-1 : 201 0, Clause 5, I EC 62052-21 : 2004, 7. 3. 2. 3, I EC 62053-1 1 : 2003,
7. 4 an d I EC 62053-21 : 2003, 7. 4.
Th e a . c.
p o we r- fre que n cy vo lta ge te st m e th od s p e cifie d in 6. 1 0. 2. 5 is us e d.
Th e te s t vo lta ge
sh a ll b e a p p lie d for 1 m in .
Ca p a citors
in te rfe rin g
te s tin g ca n
be
with
con side re d.
th e
a . c.
vo lta ge
If ca p a citors
a re
te stin g
may
re m ove d,
be
th is
disco n n e cte d,
sh a ll b e
or
d. c.
do cum e n te d in
vo lta ge
th e
te st
re p ort.
Th e te st s h a ll b e p e rfo rm e d a s s p e cifie d in Ta b le 25. Circuits n ot in vo lve d in th e te st sh a ll b e
con n e cte d
toge th e r
and
to
th e
e a rth .
Th e
te st
volta ge
te rm in a ls. For e xa m p le s of te st a rra n ge m e n ts s e e A n n e x F.
s h a ll
be
a p p lie d
dire ctly
to
th e
I EC 62052-31 :201 5 © I EC 201 5
– 1 09 –
T a b l e 2 5 – AC v o l t a g e t e s t
AC
P o i n ts o f a p p l i c a ti o n
t e s t v o l t a g e V r. m . s .
o f t h e t e s t vo l ta g e
a) Between, on th e one hand, all m ains circuits
connected tog ether, an d, on th e other h and, earth
b) Between m ains circuits not intend ed to be
connected tog ether in service
P ro t e c t i v e c l a s s I
P ro t e c t i v e c l a s s I I
The valu es of Tabl e 1 1
for basic insu lation appl y.
The valu es of Tabl e 1 1
for reinforced i nsul ation
appl y.
The val ues of Tabl e 1 1 for basi c insulation apply.
For electromechanical meters, additional tests are specified in Annex G.
For performing AC voltage test as routine test, see Annex I.
6. 1 0 . 4. 4
D i e l e c t ri c t e s t s o n
6. 1 0 . 4. 4. 1
s u b -as s em b l i e s
O v e rv i e w
NOTE 1 The followin g is based on I EC 60664-1 : 2007, 6. 1 . 1 and 6. 1 . 2.
If full verification of insulation through testing on complete equipment is not possible,
additional verification of individual clearances and solid insulations may be necessary; see
6. 10. 4. 1.
Clearances and solid insulation in mains circuits are verified by the impulse voltage test,
simulating the stresses caused by transient overvoltages. The impulse voltage test may be
substituted by an a.c. voltage test or a d.c. voltage test.
Clearances and solid insulation in non-mains-circuits are verified by an a. c. voltage test or a
d.c. voltage test.
While tests with a.c. or d.c. voltages of the same peak value as the impulse test voltage
specified can be used to verify the withstand capability of clearances, they more highly stress
solid insulation because the voltage is applied for longer duration. They can overload and
damage certain solid insulations. Therefore, these test methods shall be used with caution.
When verifying insulation within equipment by a voltage test, it is necessary to ensure that the
specified test voltage appears at the tested insulation. Protective impedance and voltagelimiting devices in parallel with the insulation to be tested shall be disconnected. Such
modifications of the EUT shall be properly documented.
6. 1 0 . 4. 4. 2
6. 1 0 . 4. 4. 2 . 1
V e ri fi c a t i o n
o f c l e a ra n c e s i n
m a i n s c i rc u i t s
I m pu l s e vol tag e te s t
The purpose of this test is to verify that clearances will withstand specified transient
overvoltages. The impulse voltage test is intended to simulate overvoltages of atmospheric
origin and covers overvoltages due to switching of low-voltage equipment.
The impulse voltage test method specified in 6. 10. 2. 3 is used.
The test voltage shall be as specified in Table 7.
The altitude correction factors specified in 6. 10. 2. 7 apply.
The supplier and the purchaser may agree on higher test values.
– 110 –
I EC 62052-31 :201 5 © I EC 201 5
NOTE When testing clearances, associated solid insulation will be subjected to the test voltage. As the impulse
test voltage is increased for higher altitudes, solid insulation will have to be designed accordingly. This results in
an increased impulse withstand capability of the solid insulation.
6. 1 0 . 4. 4. 2 . 2
AC p o w e r- fre q u e n c y v o l t a g e t e s t
Alternatively, clearances may be verified using the a.c. power-frequency voltage test method
specified in 6. 10. 2. 5. The peak value of the a.c. voltage shall be equal to the impulse test
voltage as specified in Table 7 and shall be applied for three cycles of the a.c. test voltage.
The altitude correction factors specified in 6. 10. 2. 7 apply.
6. 1 0 . 4. 4. 2 . 3
D C vo l tag e te s t
Alternatively, clearances may be verified using d.c. voltage test method specified in 6. 10. 2. 6.
The average value of the d.c. voltage shall be equal to the impulse test voltage as specified in
Table 7 and applied three times for 10 ms in each polarity.
The altitude correction factors specified in 6. 10. 2. 7 apply.
6. 1 0 . 4. 4. 3
V e ri fi c a t i o n
o f c l e a ra n c e s i n n o n - m a i n s - c i rc u i t s
Clearances in non-mains-circuits – see 6. 7. 4. 2 – shall be verified using the a.c. powerfrequency voltage test method specified in 6. 10. 2. 5.
The test voltages shall be as specified Table 13. The duration of the test shall be 5 s.
Alternatively, the test may be performed using the d.c. voltage test method specified in
6. 10. 2. 6. The test voltages shall be as specified in Table 13 but multiplied by √2. The duration
of the test shall be 1 min.
The altitude correction factors specified in 6. 10. 2. 7 apply.
6. 1 0 . 4. 4. 4
6. 1 0 . 4. 4. 4. 1
V e ri fi c a t i o n
of sol i d
i n s u l ati on
G e n e ra l
Solid insulation in mains circuits shall be verified by:
a)
b)
c)
d)
the impulse voltage test specified in 6.10. 4.4.4. 2; and / or
the 5 s a.c. voltage test as specified in 6. 10. 4. 4. 4. 3; and / or
the 1 min a.c. voltage test as specified in 6.10.4.4. 4. 4; and / or
the 1 min d.c. voltage test as specified in 6. 10.4.4. 4. 5.
The kind of test used and the test voltages shall be as specified for the relevant situation.
6. 1 0 . 4. 4. 4. 2
I m p u l s e vo l tag e te s t
The impulse voltage test method specified in 6.10. 2. 3 is used to verify the capability of the
solid insulation to withstand the rated impulse voltage.
For verifying solid insulation in mains circuits – see 6.7.3. 4. 1 – the test voltages shall be as
specified in Table 10. Altitude correction factors specified in 6. 10.2. 7 do not apply.
The supplier and the purchaser may agree on higher test values.
I EC 62052-31 :201 5 © I EC 201 5
– 111 –
Th e te st sh a ll b e co n ducte d for te n im p uls e s o f e a ch p ola rity with a n in te rva l o f a t le a st 1
s
b e twe e n im p ulse s .
6. 1 0. 4. 4. 4.3
Th e 5 s a. c. power-freq u en cy vol tag e test
Th e a . c. p o we r-fre que n cy vo lta ge te st m e th o d s p e cifie d in 6. 1 0. 2. 5 is use d with a dura tion o f
5 s.
a)
for ve rifyin g s o lid in s ula tio n in m a in s circuits – s e e 6. 7. 3. 4 . 1 –
th e te s t vo lta ge s sh a ll b e
a s s p e cifie d in Ta b le 1 0;
b)
for ve rifyin g s o lid in sula tion in n o n -m a in s circuits – s e e 6. 7. 4 . 4 . 1
be
as
sp e cifie d
in
Ta b le
re in fo rce d in s ula tion ,
13
fo r
b a s ic
in sula tion
and
th e va lue s a re m ultip lie d b y 1 , 6.
– th e te st volta ge sh a ll
sup p le m e n ta ry
A dditio n a lly,
in sula tio n .
Fo r
if th e wo rkin g vo lta ge
e xce e ds 300 V, th e n th e te s t s p e cifie d in 6. 1 0. 4 . 4 . 4. 4 c) s h a ll b e p e rform e d.
6. 1 0. 4. 4. 4.4
Th e a . c.
Th e 1 m in a.c. vol tage test
p owe r-fre q ue n cy vo lta ge te s t m e th o d s p e cifie d in 6. 1 0. 2. 5 is us e d for a dura tio n o f
1 m in .
a)
for ve rifyin g s olid in sula tion in m a in s circuits – s e e 6. 7. 3. 4. 1 –,
th e te st vo lta ge s s h a ll b e
a s sp e cifie d in Ta b le 1 1 ;
If th e
1
m in
a . c.
vo lta ge
te st is
p e rform e d with
th e
te st vo lta ge s s p e cifie d in
Ta b le
1 0,
th e re is n o n e e d to re p e a t th e te st with th e volta ge s sp e cifie d in Ta b le 1 1 .
b)
for ve rifyin g
re in force d
th in
film
in sula tion
in
m a in s
circuits
–
see
6. 7. 3. 4. 4
–
th e
te st
vo lta ge s s h a ll b e a s sp e cifie d in Ta b le 1 0 for re in force d in s ula tio n a n d a p p lie d to two o f
th e th re e la ye rs;
c)
for ve rifyin g
so lid
in s ula tio n
vo lta ge e xce e ds 300 V,
in sula tion
and
in
n on - m a in s
circuits
–
se e
6. 7. 4 . 4 . 1
–
wh e n
th e
workin g
th e te st vo lta ge s h a ll b e 1 , 5 tim e s th e workin g vo lta ge fo r b a s ic
sup p le m e n ta ry
in sula tio n
and
twice
th e
wo rkin g
volta ge
for
re in fo rce d
in sula tion ;
d)
for ve rifyin g re in force d th in film in sula tio n in n o n -m a in s circuits – se e 6. 7. 4 . 4 . 4 – th e te st
vo lta ge s sh a ll b e a s s p e cifie d in Ta b le 1 3 m ultip lie d b y 1 , 6 for re in fo rce d in sula tion a n d
a p p lie d to two o f th e th re e la ye rs .
6. 1 0. 4. 4. 4. 5
Th e 1 m in d. c. voltag e test
NOTE The fol lowing is based on I EC 60664-1 : 2007, 6. 1 . 3. 6.
In so m e ca s e s th e 1 m in a . c. vo lta ge te s t n e e ds to b e sub s titute d b y a 1 m in d. c. vo lta ge te st
of a va lue e qua l to th e p e a k va lue o f th e a . c. vo lta ge , h o we ve r th is te st will b e le ss strin ge n t
th a n th e a . c. vo lta ge te st.
Th e d. c. vo lta ge te s t with a te s t vo lta ge e qua l to th e p e a k va lue of th e a . c. vo lta ge is n o t fully
e quiva le n t
to
th e
a . c.
vo lta ge
te st
due
in sula tio n for th e s e typ e s of vo lta ge s.
to
th e
diffe re n t
with sta n d
ch a ra cte ristics
Ho we ve r in th e ca se o f a p ure d. c.
o f solid
vo lta ge stre ss,
th e
d. c. vo lta ge te st is a p p ro p ria te .
Th e d. c. vo lta ge te st m e th o d sp e cifie d in 6. 1 0. 2. 6 is us e d.
For ve rifyin g re in fo rce d th in
on ly b y d. c.
vo lta ge ,
film
in s ula tio n
in
n o n - m a in s circuits – se e
6. 7. 4 . 4. 4 – stre sse d
th e te s t vo lta ge s sh a ll b e a s sp e cifie d in Ta b le 1 3 m ultip lie d b y 1 , 6 for
re in fo rce d in s ula tio n a n d a p p lie d to two o f th e th re e la ye rs .
6. 1 0. 4. 4. 4.6
Pass / fail cri teri a
NOTE 1 This subclause is based on I EC 60664-1 : 2007, 6. 1 . 3. 3. 2.
No
p un cture
disch a rge s
or p a rtia l b re a kdo wn
a re
a llowe d.
Pa rtia l
of s o lid in s ula tio n
b re a kdo wn
will
be
sh a ll occur durin g th e
in dica te d
by
a
ste p
te st,
in
b ut p a rtia l
th e
re sultin g
– 112 –
I EC 62052-31 :201 5 © I EC 201 5
waveshape which will occur earlier in successive impulses. Breakdown on the first impulse
may either indicate a complete failure of the insulation system or the operation of overvoltage
limiting devices in the equipment.
If overvoltage limiting devices are included in the equipment, care should be taken to examine
the waveshape to ensure that their operation is not taken to indicate insulation failure.
Distortions of the impulse voltage which do not change from impulse to impulse may be
caused by operation of such overvoltage limiting device and do not indicate a (partial)
breakdown of solid insulation.
NOTE 2 Partial discharges in voids can lead to partial notches of extremely short durations which may be
repeated in the course of an impulse.
6.1 0.4.4.5
Dielectric tests in circuits specified in 6.7.5 – Verification of clearances in
circuits with special overvoltage valu es
For verification of clearances in circuits described in 6. 7. 5.1 a) to c) the impulse voltage test
method specified in 6.10. 2. 3 or the a.c. voltage test method specified in 6. 10. 2. 5 with a
duration of at least 5 s shall be used using the applicable voltage from Table 17 for the
required clearance. The altitude correction specified in 6. 10. 2. 7 applies.
6.1 0.5
Electrical tests on cu rrent circuits of direct connected meters without supply
control switches (SCSs)
Current circuits of direct connected m eters shall withstand sim ulated short-circuit currents –
as m ay be experienced under short-circuit conditions in m etering installations – and stay safe.
Conformity is checked by the following test.
Test conditions:
•
•
•
•
test circuit as shown in Annex E, comprising the following elements in series:
– a voltage source with a voltage of 1, 15 Ue and with reference frequency;
– the metering equipment under test and;
– load to produce the required test current;
prospective test current as specified in Table 22, line 11. The power factor shall be as
specified in Table 27;
test voltage tolerance +5 % …–5 %;
test current tolerance +5 % …–0 %.
Test method:
•
•
•
the test switch shall be closed at the zero voltage crossover and opened at the first
subsequent zero voltage crossover, thus remaining in the closed position for one half
cycle of the supply voltage;
repeat the test 3 times on the same specimen with an interval of at least 1 min between
each test;
for polyphase meters, the test may be performed phase by phase.
Pass / fail criteria:
•
it is permissible that the current circuit may be damaged but no hazardous live parts shall
be exposed, no fire shall occur, or if it occurs, it shall be contained in the meter.
I EC 62052-31 :201 5 © I EC 201 5
6.1 0.6
6.1 0.6.1
– 113 –
Electrical tests on cu rrent circuits of direct connected meters with SCSs
Test sequence and sample plan
This subclause 6. 10.6 further details the requirements specified in 6. 9. 8. 4 and specifies test
methods to verify conformity. Table 26 summarizes the test sequence and sample plan.
For the purposes of the tests given in this subclause 6. 10. 6, the supply control switch(es)
shall be considered as an integral part of the meter equipment and each test shall be
performed on the metering equipment as a complete unit. Polyphase supply control switches
constructed as a single unit shall be tested as a single unit. The supply side input terminals
and the load side output terminals of the meter shall be taken to be the effective terminals of
the supply control switches. Example diagrams of meters with switches are given in Annex C.
In the case of a polyphase meter, the tests and test values given shall apply to each phase.
Table 26 – Test sequence and sample plan for supply control switches
Test
number
Test clause
SCS Sample
1
2
3
4
*
*
*
1
0
Pre-conditi oni ng
*
2
6. 1 0. 6. 3
Switch ing th e neutral by the su ppl y control switch
*
3
6. 1 0. 6. 4
Endurance / Num ber of operati ng cycles
*
4
6. 1 0. 6. 5
Surg e voltag e withstand across open contacts
5
6. 1 0. 6. 6
Verification of the abil ity to carry th e rated safe sh ort-tim e
withstan d current ( Issw )
6
6. 1 0. 6. 7
Verification of the abil ity to carry th e rated operati on al short-ti m e
withstan d current ( Io sw )
7
6. 1 0. 6. 8
Verification of the abil ity to m ake the rated short-ci rcuit current
( Ism )
8
6. 1 0. 6. 9
Min im um switched current (pass / fail criterion)
*
*
*
*
9
6. 1 0. 6. 1 0
Power consum ption (pass / fail criteri on )
*
*
*
*
10
6. 1 0. 6. 1 1
Diel ectric test (pass / fail criterion )
*
*
*
*
*
*
*
*
The * in th e tabl e ind icates that the particul ar test should be perform ed on the particu lar sam ple, but th e
sequence of th e tests shall al ways follow the sam e order as the test num ber sequ ence. For exam ple: SCS
sam ple 1 shall be subjected to test num bers 1 , 2, 3, 8, 9 and 1 0, in th at specific order.
SCS sam ple 3 m ight n ot be requi red, depen din g on th e resul t of test 5 on SCS sam ple 2. Test 8, 9 an d 1 0 on
SCS sam ple 2 has to be carri ed out only if th e switch rem ains operational after test 5.
6.1 0.6.2
Pre-conditioning
NOTE This subcl ause is based on I EC 62055-31 : 2005.
This test shall be carried out as pre-conditioning before the short-circuit current tests to
“settle” the switch contacts. I t shall also be carried out after the endurance test to establish if
the EUT passed the test or not.
The test shall be performed as follows:
•
•
•
configure the EUT so that the contact tested is in the closed position;
set voltage and current in the supply control circuit to Un , Im ax and PF = 1 , 0;
apply conditions that lead to the contact to be opened. The conditions for opening – and
closing – depend on the function of the switch and should be specified by the
manufacturer;
– 114 –
I EC 62052-31 :201 5 © I EC 201 5
•
ve rify th a t th e switch o p e n s a t th e first a tte m p t;
•
a p p ly co n ditio n s th a t le a d to th e co n ta ct clos e d;
•
ve rify th a t th e switch clo se s a t th e first a tte m p t;
•
th e re s h a ll b e n o e vide n ce of stickin g of th e con ta cts;
•
re p e a t th e te st 3 tim e s .
Wh e re a switch h a s a m e ch a n ica l a ctua tin g le ve r th e n te st fo r trip - fre e o p e ra tio n b y re p e a tin g
th e te st a s fo llo ws:
•
p ush th e le ve r in th e dire ctio n for clo sin g of th e con ta cts, th e n h old it a t th e n e a re st p o in t
wh e re
th e
s up p ly con tro l switch
co n ta cts
h a ve
just m a de
co n ta ct.
Ca us e
th e
s witch
to
op e n . Re p e a t th e te s t th re e tim e s.
Th e te s t is p a ss e d if th e switch trip s for th e firs t a tte m p t e a ch tim e .
6.1 0.6.3
Switching the neutral by the supply control switch
Switching the neutral of a three-phase-four wire direct connected meter by the suppl y control
switch is an optional requirement. When the neutral is switched:
•
•
•
when the switch is opening, the contacts switching the live circuits shall break first and the
contacts switching the neutral shall break last;
when the switch is closing, the contacts switching the neutral shall m ake first and the
contacts switching the live circuits shall m ake after;
all other requirements are the same as for the poles switching the phases.
Co n form ity is ch e cke d b y in s p e ctio n .
6.1 0.6.4
Endurance / number of operating cycles
NOTE 1 This test strictly speaking is not a safety test, as th e supply control switch is expected to rem ain operable
at the en d of the test. However, the ability to switch m inimum current an d keeping specified power consum ption
lim its after perform ing the end urance test have safety im plications. For this reason this test is specified here.
Each suppl y control switch shall be capable of carrying out the number of operations specified
in Table 22.
I n the case of a polyphase m eter, each phase has to be tested. This can be perform ed on the
sam e sam ple phase-by-phase one after the other or on different sam ples separatel y.
Co n fo rm ity is ch e cke d b y th e fo llo win g te st ca rrie d o ut o n a n e w te st s p e cim e n (SCS sa m p le
1 , s e e Ta b le 26) . Th e m e th od for a ctua tin g th e switch sh a ll b e sp e cifie d b y th e m a n ufa cture r.
For th is te s t, o th e r trigge rs co n tro llin g th e switch un de r te s t s h a ll b e dis a b le d.
•
th e te s t circuit e sse n tia lly co m p rise s th e sup p ly s ource , a n ove rcurre n t
p rote ctive de vice ,
th e m e te rin g e q uip m e n t un de r te s t a n d a loa din g im p e da n ce ;
•
th e vo lta ge s h a ll b e s e t to
Ue ;
NOTE 2 This is a reduced req uirem ent com pared to what is specified i n I EC 62055-31 : 2005, Clause C. 3.
•
•
th e curre n t sh a ll b e s e t to
Ie ,
a n d th e p owe r fa cto r sh a ll b e s e t to 1 , 0;
n um b e r o f o p e ra tin g cycle s sh a ll b e a s s p e cifie d in Ta b le 22,
lin e 6,
with 1 0 s m a ke a n d
20 s b re a k tim e ;
•
th e te s t s h a ll b e re p e a te d usin g th e sa m e sa m p le ,
e xce p t th a t th e p owe r fa ctor s h a ll b e
se t to 0, 5.
Th is te s t im p licitly te s ts th e ra ted m a kin g a n d b re a kin g ca p a city.
I EC 62052-31 :201 5 © I EC 201 5
– 115 –
The test is passed if during the test the switch shows no signs of malfunction, sticking of
contacts or reluctance to latch and after the test:
•
•
•
•
•
the switch is not damaged and no live parts are exposed;
the switch operates normally as specified in 0;
the switch is capable to switch the minimum switched current as specified in 6. 10. 6. 9;
the power consumption does not exceed the limits specified in 6. 10. 6. 10;
the switch passes the dielectric test specified in 6. 10. 6. 11.
In the case of multi-pole (e. g. three-phase) switches, the conditions shall be met by each
pole.
6. 1 0. 6. 5
Su rg e vol tage with stan d across open con tacts
Meters equipped with (a) suppl y control switch(es) shall withstand simulated lightning-induced
comm on m ode and differential mode voltage surges as might be expected in residential
installations, while the suppl y control switch contacts are in the open position.
NOTE 1 This test is specifically d esign ed for the case where th ere is internal electri cal coupli ng of circuits
between th e input and output term inals of the m eter wh en the suppl y control switch contacts are in the open
condition. The test stresses these coupl ing elem ents.
Conformity is checked by the surge test specified in 6. 10. 2.4, carried out on a new test
specimen (SCS sample 4, see Table 26) as follows:
For this test, all triggers controlling the switch under test shall be disabled.
•
•
•
•
•
•
•
meter in non-operating mode, with the contacts of the supply control switch in open
position;
the test voltage shall be applied across the terminals of the current circuit which contains
the supply control switch. All other terminals shall be connected to earth;
if there is more than one supply control switch, the test shall be applied to each in
sequence;
repetition rate not faster than 1 impulse per minute;
test level increased from zero in 1 000 V steps until contact tips flash over, but not more
than 12 000 V;
number of surges at each test level: five positive and five negative pulses each;
the voltage at which the contact tips flash over shall be recorded.
NOTE 2 Flash -over can be detected by observation an d by a collapse of th e waveform .
I n the case when the neutral is switched, additional comm on mode voltage tests in addition to
the surge voltage test across the open contacts m ay be agreed between the supplier and the
purchaser.
Pass / fail criteria: there shall be no permanent damage to any part of the meter including the
components connected across the poles of the switch and if after the test:
•
•
•
the switch is capable to switch the minimum switched current as specified in 6. 10. 6. 9;
the power consumption does not exceed the limits specified in 6. 10. 6. 10;
the switch passes the dielectric test specified in 6. 10. 6. 11.
NOTE 3 Integrity of the components connected across the poles of the switch can be established by
inspection or by a functional test as specified by the manufacturer.
– 116 –
6.1 0.6.6
I EC 62052-31 :201 5 © I EC 201 5
Verification of the ability to carry the rated safe short-time withstand current
Meters equipped with (a) suppl y control switch(es) shall withstand simulated short-circuit
currents – as m ay be experienced under short-circuit conditions in m etering installations –
and stay safe.
Conformity is checked by the following test carried out on a new test specimen (SCS sample
2, see Table 26).
Test conditions:
•
•
•
•
test circuit as shown in Annex E, comprising the following elements in series:
– a voltage source with a voltage of 1, 15 Ue and with reference frequency;
– the metering equipment under test with the supply control switch in closed position;
– load to produce the required test current; and
– a test switch;
prospective test current as specified in Table 22, line 11. The power factor shall be as
specified in Table 27;
test voltage tolerance +5 % …–5 %;
test current tolerance +5 % …–0 %.
Table 27 – Power factor ranges of the test circuit
Test current
A
I≤
1 500
0, 93 to 0, 98
1 500
< I≤
3 000
0, 85 to 0, 90
3 000
< I≤
4 500
0, 75 to 0, 80
4 500
< I≤
6 000
0, 65 to 0, 70
1 0 000
0, 45 to 0, 50
6 000
NOTE 1
Corresponding power factor range
< I≤
These values are from I EC 60898-1 : 201 5, Table 1 7.
NOTE 2 The phase shift is caused by a com binati on of resistors an d reactors.
The test shall be performed as follows:
•
•
•
the test switch shall be closing at zero voltage crossover and opening at the first
subsequent zero voltage crossover, thus remaining in the closed position for one half
cycle of the supply voltage;
repeat the test 3 times on the same specimen with an interval of at least 1 min between
each test;
plot a graph of the voltage and the test current waveform during each test and verify that
the test was executed as is required. The graphs shall be attached to the test report.
Acceptance conditions: it is permissible that the contacts may weld or burn away but no
hazardous live parts shall be exposed, no fire shall occur, or if it occurs, it shall be contained
in the meter.
If the switch remained operational, and if after the test:
•
•
it meets the acceptance conditions of 6. 10.6. 9, Minimum switched current;
it meets the acceptance conditions of 6. 10.6. 10, Power consumption;
I EC 62052-31 :201 5 © I EC 201 5
•
– 117 –
it meets the acceptance conditions of 6. 10.6. 11, Dielectric test
the tests specified in 6. 10. 6. 7 do not need to be performed.
6. 1 0. 6. 7
Veri fi cati on of th e abi l ity to carry th e rated operati on al sh ort-ti m e with stan d
cu rren t
Meters equipped with (a) suppl y control switch(es) shall withstand simulated short-circuit
currents – as m ay be experienced under short-circuit conditions in m etering installations –
and stay operational.
I f the test “stay safe” test is passed and the requirem ents for “stay operational” are also met,
then the “stay operational” test need not be perform ed.
Conformity is checked by the same test as specified in 6. 10. 6. 6, but the prospective test
current test shall be as specified in Table 22, line 12, and the test shall be carried out only
once, on a new test specimen (SCS sample 3, see Table 26).
Acceptance conditions:
•
•
•
•
•
during the test the supply control switch shall not open;
after the test the supply control switch shall show no signs of malfunction, sticking or
welding of contacts or reluctance to latch;
after the test it shall meet the requirements of 6. 10. 6. 9, Minimum switched current;
after the test it shall meet the requirements of 6. 10. 6. 10, Power consumption;
it shall pass the dielectric test specified in 6. 10. 6. 11.
NOTE For additi onal function al an d accuracy req uirem ents, see the relevant stand ards.
6. 1 0. 6. 8
Verifi cati on of th e abi lity to m ake th e rated sh ort-ci rcu it cu rren t
Meters equipped with (a) suppl y control switch(es) shall withstand making into sim ulated
short-circuit currents – as may be experienced under short-circuit conditions in metering
installations – and stay safe and operational.
Conformity is checked with the following test, carried out on a new test specimen (SCS
sample 4, see Table 26).
Test conditions:
•
•
•
•
test circuit as shown in Annex E, comprising the following elements in series:
– a voltage source voltage with a voltage of 1,15 Ue and with reference frequency;
– the metering equipment under test with the supply control switch in open position;
– load to produce the required test current;
– and a test switch;
prospective test current as specified in Table 22, line 13, power factor as specified in
Table 27;
test voltage tolerance +5 % …–5 %;
test current tolerance +5 % …–0 %.
The test shall be performed as follows:
•
close the switch under test to close into the prospective test current. The switch should
remain in the closed position.
– 118 –
I EC 62052-31 :201 5 © I EC 201 5
It is not permitted to allow the supply control switch to be activated under the control of the
external test equipment, because it could possibly negate special techniques that the
meter application process may employ, such as zero point switching. The load switch
contacts thus have to be caused to close under the direct control of the EUT itself.
•
•
•
•
the test current shall be maintained to flow up to the first zero point crossing of the
current, at which point the test equipment shall disconnect the voltage source;
after the test, the switch shall be opened;
repeat the test 3 times on the same sample with a min. delay of 1 min between each test;
plot a graph of the voltage and the test current waveform during each test and verify that
the test was executed as is required.
During and after the test the following requirements shall be met:
•
•
•
•
•
contacts shall open on the first attempt after each make operation;
the supply control switch shall show no signs of malfunction, sticking or welding of
contacts or reluctance to latch;
after the test the switch shall meet the requirements of 6. 10. 6. 9, Minimum switched
current;
after the test the switch shall meet the requirements of 6.10.6. 10, Power consumption;
after the test the switch shall pass the dielectric test specified in 6.10. 6.11.
It is recognised that there may be significant statistical variance in the result of this test. A
more exact method is under consideration.
6. 1 0. 6. 9
M in imu m swi tch ed cu rren t (pass / fail cri terion )
As part of the pass / fail criteria of the tests specified above (see Table 26), it shall be verified
that the suppl y control switch that have been tested is capable to switch the m inim um current.
Compliance is verified with the following test:
•
•
•
•
metering equipment in normal operating condition;
test voltage at Ue ;
test current equal to the starting current of the meter, and cos φ= 1 ;
10 operating cycles at approximately 10 s closed and 20 s open.
NOTE One operating cycle of the supply control switch is one make followed by one break action.
For the purpose of this test, the manufacturer may provide an external means, which allows
for the opening and closing of the supply control switch to be under the control of the test
equipment.
Acceptance conditions:
•
•
the supply control switch shall successfully conduct the test current each time the contacts
are in the closed position;
the supply control switch shall successfully break the test current each time the contacts
are in the open position.
6. 1 0. 6. 1 0 Power con su mpti on (pass / fai l criterion )
As part of the pass / fail criteria of the tests specified above (see Table 26), it shall be verified
that the power consumption of the current circuit that com prises the suppl y control switch that
have been tested does not exceed the values specified here.
I EC 62052-31 :201 5 © I EC 201 5
– 119 –
I f the neutral is also switched, the test also applies to the neutral circuit.
NOTE This subcl ause is based on I EC 62055-31 : 2005, 7. 3. 2.
Co m p lia n ce is ve rifie d with th e fo llowin g te st:
Th e curre n t circuit sh a ll b e loa de d with th e ra te d op e ra tio n a l volta ge a n d m a xim um curre n t of
, cos φ= 1
th e m e te r
a t re fe re n ce fre q ue n cy a n d te m p e ra ture , for a dura tio n o f 1 0 m in .
A cce p ta n ce co n ditio n s: Th e a p p a re n t p o we r ta ke n s h a ll n ot e xce e d a va lue in VA e quiva le n t
to 0, 08 % o f
Un
in vo lts m ultip lie d b y 1 00 % o f
Im a x
in a m p e re s .
EXAMPLE 230 V and 60 A gi ves 1 1 , 0 VA; 230 V an d 1 00 A gives 1 8, 4 VA.
6.1 0.6.1 1 Dielectric test (pass / fail criterion)
As part of the pass / fail criteria of the tests specified above (see Table 26), it shall be verified
that the open contacts of the load switch can withstand an im pulse voltage test of 2 kV and an
a. c. test voltage of 1 kV r.m. s. for 1 min.
Th e te st s h a ll b e p e rform e d a s fo llows :
•
in th e ca se wh e re th e n e utra l lin e is n o t switch e d, th e sup p ly side curre n t circuit te rm in a ls
on th e o n e h a n d a s we ll a s th e loa d side curre n t circuit te rm in a ls o n th e oth e r h a n d a re
co n n e cte d to ge th e r. A ll o th e r te rm in a ls a re con n e cte d to e a rth ;
•
in th e ca s e wh e re th e n e utra l lin e is switch e d,
th e sup p ly s ide curre n t circuit a n d n e utra l
te rm in a ls o n th e o n e h a n d a s we ll a s th e lo a d s ide curre n t circuit a n d th e n e utra l te rm in a ls
a re con n e cte d to ge th e r. A ll oth e r te rm in a ls a re co n n e cte d to e a rth ;
•
th e m e te r sh a ll b e in n o n -op e ra tin g con ditio n ;
•
th e s up p ly co n tro l switch sh a ll b e in th e o p e n p os ition ;
•
th e im p uls e vo lta ge te s t a s s p e cifie d in 6. 1 0. 2. 3 s h a ll b e
p e rform e d with a vo lta ge o f 2 kV
a p p lie d b e twe e n th e two gro up s of te rm in a ls;
•
th e
a . c.
vo lta ge
te s t a s
sp e cifie d in
6. 1 0. 2. 5 sh a ll b e
p e rform e d with
a
vo lta ge
of 1
kV
a p p lie d b e twe e n th e two gro up s of te rm in a ls for 1 m in ;
•
th e le a ka ge curre n t s h a ll b e re corde d.
6.1 0.7
6.1 0.7.1
Electrical tests on load control switches (LCSs)
Test sequ ence and sample plan
Th is sub cla use 6. 1 0. 7 furth e r de ta ils th e re quire m e n ts s p e cifie d in 6. 9. 8. 5 a n d s p e cifie s te s t
me th o ds to ve rify co n form ity. Ta b le 28 sum m a rize s th e te st se que n ce a n d sa m p le p la n .
– 1 20 –
I EC 62052-31 :201 5 © I EC 201 5
Table 28 – Test sequence and sample plan for load control switches
Test
number
Test clause
LCS Sample
1
2
3
4
5
*
*
*
*
1
6. 1 0. 7. 2
Pre-conditi oni ng
*
2/1
6. 1 0. 7. 3
Endu rance / Num ber of operati ng cycles Test 2/1
*
2/2
6. 1 0. 7. 3
Endu rance / Num ber of operati ng cycles Test 2/2
2/3
6. 1 0. 7. 3
Endu rance / Num ber of operati ng cycles Test 2/3
3
6. 1 0. 7. 4
Verification of the abil ity to carry th e rated conditi onal
safe short-circuit cu rrent ( Icssw )
4
6. 1 0. 7. 5
Verification of the abil ity to carry the rated conditi onal
operati onal short-circuit cu rrent ( Ico sw )
5
6. 1 0. 7. 6
Power consum ption (pass / fail criteri on )
*
*
*
*
*
6
6. 1 0. 7. 7
Diel ectric test (pass / fail criterion )
*
*
*
*
*
*
*
*
*
The * in the table in dicates th at the particular test shoul d be perform ed on th e particul ar LCS sam ple.
LCS sam ple 5 m ight not be req uired, dependi ng on the result of test 3 on LCS sam ple 4. Test 5 and 6 on LCS
sam ple 4 has to be carried out onl y if the switch rem ains operation al after test 3.
For the purposes of the tests given in this subclause 6. 10. 7, the load control switch(es) shall
be considered as an integral part of the metering equipment and each test shall be performed
on the metering equipment as a complete unit. Polyphase load control switches constructed
as a single unit shall be tested as a single unit. The terminals of the metering equipment shall
be taken to be the effective terminals of the load control switches. Example diagrams of
meters with load control switches are given in Annex C.
6.1 0.7.2
Pre-conditioning
Subclause 0 applies.
6.1 0.7.3
Endurance / number of operating cycles
NOTE This test strictly speaking is not a safety test, as the load control switch is expected to rem ain operable at
the end of the test. However, the ability to keep specifi ed power consum ption lim its after perform ing th e end urance
test has safety im plications. For this reason this test is specifi ed h ere.
Load control switches shall be capable of carryin g out the number of operations specified in
Table 23.
Conformity is checked by the following tests carried out on a new test specimen. For this test
three load switches and therefore, possibly more than one metering equipment are required.
The method for actuating the switch shall be specified by the manufacturer. For this test,
other triggers controlling the switch under test shall be disabled.
•
•
•
•
•
the test circuit essentially comprises the supply source, an overcurrent protective device,
the metering equipment under test and a loading impedance;
the voltage shall be set to Ue ;
number of operating cycles shall be as specified in Table 23 line 6. Number of switching
operation per minute shall not exceed 6 per minute;
test 2/1 shall be performed on LCS sample 1, with a test current set to Ie , as shown in
Table 23 line 3a, and power factor shall be set to 1, 0. This test implicitly tests the rated
making and breaking capacity;
test 2/2 shall be performed on LCS sample 2 with a reduced current as shown in Table 23
line 3b and the power factor set to 0,4. The loading impedance consists of a resistance
and inductance in series (if an air-core inductor is used a resistor passing at least 0, 6 % of
the coil current shall be connected in parallel with it);
I EC 62052-31 :201 5 © I EC 201 5
•
– 1 21 –
test 2/3 shall be performed on LCS sample 3 without current.
The test is passed if during the test the switch shows no signs of malfunction, sticking of
contacts or reluctance to latch and after the test:
•
•
•
•
the switch is not damaged and no live parts are exposed;
the switch operates normally as specified in 6.10. 7.2;
the power consumption does not exceed the limits specified in 6. 10. 7. 6;
the switch passes the dielectric test specified in 6. 10. 7. 7.
6. 1 0. 7. 4
Veri fi cati on of th e abi l ity to carry th e rated con di ti on al safe sh ort-ci rcu it
cu rren t ( Icssw )
Load control switches shall withstand sim ulated short-circuit currents – as may be
experienced under short-circuit conditions in m etering installations – and stay safe.
Conformity is checked by the following test carried out on a new test specimen (LCS sample
4, see Table 28).
Test conditions:
•
•
•
•
test circuit comprising the following elements connected in series:
– a voltage source voltage Ue , with reference frequency;
– a fuse, conforming to IEC 60269-3, with a rated current equal to, or immediately above,
the rated operational current (at power factor = 1 ) of the switch. The characteristics of
the fuse shall be agreed between the manufacturer and the purchaser and shall be
included in the test report;
– the metering equipment under test, with the load switch in closed position;
– load to produce the required test current; and
– a test switch.
prospective test current as specified in Table 23 line 9. The power factor shall be as
specified in Table 27;
test voltage tolerance +5 % …–5 %;
test current tolerance +5 % …–0 %.
The test shall be performed as follows:
•
•
•
the test switch shall be closing at zero voltage crossover and opening at the first
subsequent zero voltage crossover, thus remaining in the closed position for one half
cycle of the supply voltage;
repeat the test 3 times on the same specimen with an interval of at least 1 min between
each test;
plot a graph of the voltage and the test current waveform during each test and verify that
the test was executed as is required. The graphs shall be attached to the test report.
Acceptance conditions: it is permissible that the contacts may weld or burn away but no
hazardous live parts shall be exposed, no fire shall occur, or if it occurs, it shall be contained
in the meter.
If the switch remained operational, and after the test:
•
•
it meets the requirements of 6. 10. 7. 6, Power consumption;
it passes the dielectric test specified in 6.10. 7.7
the tests specified in 6. 10. 6. 6 do not need to be performed.
– 1 22 –
6. 1 0. 7. 5
I EC 62052-31 :201 5 © I EC 201 5
Veri fi cati on of th e abi l ity to carry th e rated con di ti on al operati on al sh ortci rcu i t cu rren t ( Icosw )
Load control switches shall withstand sim ulated short-circuit currents – as may be
experienced under short-circuit conditions in m etering installations – and stay operational.
If th e te st “s ta y s a fe ” te s t is p a sse d a n d th e re quire m e n ts for “s ta y o p e ra tion a l” a re a lso m e t,
th e n th e “sta y op e ra tio n a l” te st n e e d n o t b e p e rform e d.
Co n form ity is
ch e cke d b y th e
same
te st a s
sp e cifie d in
6. 1 0. 6. 5,
b ut with
p ros p e ctive
te s t
curre n t a s sp e cifie d in Ta b le 23, lin e 1 0, a n d th e te st sh a ll b e ca rrie d o ut a n e w te s t sp e cim e n
(L CS sa m p le 5, se e Ta b le 28) .
A cce p ta n ce co n ditio n s:
•
durin g th e
te s t th e
sup p ly con trol switch
sh a ll sh ow n o s ign s o f m a lfun ctio n ,
stickin g or
we ldin g o f con ta cts o r re lucta n ce to la tch ;
•
it s h a ll m e e t th e re quire m e n ts o f 6. 1 0. 7. 6, Po we r con s um p tion ;
•
it sh a ll p a ss th e die le ctric te st sp e cifie d in 6. 1 0. 7. 7.
6. 1 0. 7. 6
Power con su mption (pass / fai l criterion )
As part of the pass / fail criteria of the tests specified above (see Table 28), it shall be verified
that the power loss of the output elem ents under rated operational current does not exceed 3
W or the voltage drop across the input and output terminals does not exceed 1 V.
6. 1 0. 7. 7
Di el ectri c test (pass / fail criteri on )
As part of the pass / fail criteria of the tests specified above (see Table 28), it shall be verified
that the open contacts of the load switch can with stand an a.c. test voltage of 1 000 V r. m. s.
for 1 m in.
Th e te s t sh a ll b e p e rform e d a s fo llo ws :
•
th e m e te rin g e q uip m e n t
•
th e lo a d co n tro l switch sh a ll b e in th e o p e n p o sitio n ;
•
th e
a . c.
vo lta ge
te st a s
sh a ll b e in n on -o p e ra tin g con ditio n ;
sp e cifie d in
6. 1 0. 2. 5 sh a ll b e
p e rfo rm e d with
a
vo lta ge
of 1 kV
a p p lie d b e twe e n th e in p ut a n d o utp ut te rm in a ls of th e lo a d switch for 1 m in ;
•
7
7. 1
th e le a ka ge curre n t s h a ll b e recorde d.
Protecti on agai nst mechani cal hazards
G en eral
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 7. 1 .
The equipm ent shall not cause a m echanical hazard in normal use, or cause a hazard in a
single fault condition that m ight not be easil y noticed. Mechanical hazards include, but are not
limited to, the following:
a) sharp edges which could cause cuts (see 7. 2);
b) falling equipm ent, resulting from breakag e of the carrying device (see 7. 3).
Co n form ity is ch e cke d a s sp e cifie d in 7. 2 a n d 7. 3.
7. 2
Sh arp edg es
NOTE 1 This subcl ause reproduces I EC 61 01 0-1 : 201 0, 7. 2.
I EC 62052-31 :201 5 © I EC 201 5
– 1 23 –
All easil y touched parts of the equipm ent shall be smooth and rounded so as not to cause
injury during normal use of the equipment.
Unless the fault presents an obvious h azard, easil y-touched parts of the equipment shall not
cause an injury in single fault condition.
Conformity is checked by inspection and, if necessary, by application of an object that
represents a finger in size, shape and hardness, to check for abrasions or cuts.
NOTE 2 An acceptable procedure is outli ned in U L 1 439.
7. 3
Provi si on s for l i fti n g an d carryi n g
NOTE This subclause is based on I EC 61 01 0-1 : 201 0, 7. 5. I t is relevant only to carryi n g handles used before
installati on of m eteri ng equi pm ent.
I f a carrying handle is fitted with the m etering equipment or supplied with it, it shall be capable
of withstanding a force of four times the weight of the equipment in normal use and in single
fault condition.
Conformity is checked by inspection and by the following test.
The carrying handle is subjected to a force corresponding to four times the weight of the
equipment. Unless the handle mounting screws (if any) are secured against loosening, one
screw is removed before performing these tests. The force is applied uniformly over a 70 mm
width at the centre of the handle or grip, without clamping. The force is steadily increased so
that the test value is attained after 10 s and maintained for a period of 1 min.
The carrying handle shall not have broken loose from the equipment and there shall not be
an y permanent distortion, cracking or other evidence of failure which could cause a hazard.
8
8. 1
Resi stance to mechani cal stresses
G en eral
Equipment shall not cause a hazard when subj ected to mechanical stresses likel y to occur in
normal use.
Conformity is checked by performing the following tests on the enclosure.
8. 2
Spri n g h am m er test
NOTE This subcl ause is based on I EC 62052-1 1 : 2003, 5. 2. 2. 1 .
The mechanical strength of the meter case shall be tested with a spring hammer (test Ehb,
see IEC 60068-2-75:2014, Clause 6).
The meter shall be mounted in its normal working position and the spring hammer shall act on
the outer surfaces of the meter cover (including windows) and on the terminal cover with a
kinetic energy of 0, 2 J. The number of impacts shall be three per location.
The result of the test is satisfactory if the meter case and terminal cover(s) do not sustain
damage which would make hazardous live parts accessible. Slight damage which does not
impair the protection against indirect contact or the penetration of solid objects, dust and
water is acceptable.
– 1 24 –
9
9. 1
I EC 62052-31 :201 5 © I EC 201 5
Protecti on ag ai n st s pread of fi re
G en e ral
NOTE 1 Cl ause 9 is based on I EC 61 01 0-1 : 201 0 Clause 9 and I EC 62052-1 1 : 2003, 5. 8.
There shall be no spread of fire outside the equipm ent in normal condition or in single fault
condition. Figure 1 1 is a flow chart showing m ethods of conform ity verification.
See also 0, Overcurrent protection.
Conformity is checked by at least one of the following methods.
a) Testing in the single fault conditions (see 4. 4) that could cause the spread of fire outside
the equipment. The conformity criteria of 4. 4.4.3 shall be met.
b) Verifying elimination or reduction of the sources of ignition within the equipment as
specified in 9.2.
c) Verifying as specified in 9. 3 that if a fire occurs it will be contained within the equipment.
These alternative methods can be applied throughout the equipment or individually for
different sources of hazards or for different areas of the equipment.
NOTE 2 Methods b) and c) are based on fulfilling specified design criteria, in contrast to method a) which relies
entirely on testing in specified single fault conditions.
NOTE 3 See 12 concerning protection against fire caused by batteries.
I EC 62052-31 :201 5 © I EC 201 5
– 1 25 –
IEC
Figure 1 1 – Flow chart to explain the requirements
for protection against the spread of fire
9.2
Eliminating or reducing the sources of ignition within the equipment
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 9. 2.
The possibility of ignition and occurrence of fire is considered to be reduced to a tolerable
level if the following requirem ents are m et:
a) the voltage, current and power available to the circuit or part of equipm ent are lim ited as
specified in 9.4.
Conformity is checked by measurement of limited-energy values as specified in 9. 4.
b) insulation between parts at different potentials meets the requirem ents for basic
insulation, or it can be demonstrated that bridging the insulation will not cause ignition.
Conformity is checked by inspection and in the case of doubt by test.
9.3
9.3.1
Containment of fire within the equ ipment, should it occur
General
The possibility of the spread of fire outside the equipm ent is considered to be reduced to a
tolerable level if the equipment and the equipm ent enclosure conform to the constructional
requirem ents of 9.3. 2.
Conformity is checked by inspection and as specified in 9. 3. 2.
– 1 26 –
9.3.2
I EC 62052-31 :201 5 © I EC 201 5
Constructional requirements
9.3.2.1
Terminal block, terminal cover, case
NOTE This subcl ause is based on I EC 62052-1 1 : 2003, 5. 8 and I EC 62055-31 : 2005, 5. 8.
The term inal block(s), insulating material retaining the m ain contacts of suppl y and load
control switches, the term inal cover(s) and the m eter case shall ensure reasonable safety
against spread of fire. I n particular, they should not be ignited by therm al overload of live
parts in contact with them .
Conformity is checked by inspection of data on materials, and in case of doubt by performing
the glow-wire test specified in IEC 60695-2-11, with the following temperatures:
•
•
•
terminal block and insulating material retaining the main contacts of supply and load
control switches in position: 960 °C ± 15 °C ;
terminal cover and meter case: 650 °C ± 10 °C ;
duration of application: 30 s ± 1 s.
The contact with the glow-wire may occur at any random location. If the terminal block is
integral with the meter base, it is sufficient to carry out the test only on the terminal block.
9.3.2.2
Connectors and insulation materials on which components are mounted
NOTE 1 This subclause reproduces I EC 61 01 0-1 : 201 0, 9. 3. 2.
NOTE 2 This subcl ause d oes not appl y to the term inal bl ock accomm odating th e term inals of the m ains circuits.
The following constructional requirem ents shall be m et:
a) Connectors and insulating material on which com ponents are m ounted shall have a
flam mability classification V-2, or better, of I EC 60695-1 1 -1 0. See also 1 3. 3 for
requirem ents for printed wiring boards.
NOTE 3 V-0 is better th an V-1 , which is better th an V-2.
Conformity is checked by inspection of data on materials, and in case of doubt by
performing the vertical burning test of IEC 60695-11-10 on samples used in the relevant
parts.
b) I nsulated wires shall retard flam e propagation.
NOTE 4 Wire with a flam mability ratin g of UL 2556 VW-1 or eq uivalent is considered to m eet this
req uirem ent.
Conformity is checked by inspection of data on materials, and in case of doubt by
performing whichever of the following tests is applicable:
1) for wires with overall cross-sectional area of the conductors exceeding 0, 5 mm 2, the
test of IEC 60332-1-2:2004;
2) for wires with overall cross-sectional area of the conductors of 0, 5 mm 2 or less, the
test of IEC 60332-2-2:2004.
9.4
Limited-energy circuit
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 9. 4.
A limited-energy circuit is a circuit that meets all the following criteria.
a) The voltage appearing in the circuit is not m ore than 30 V r. m. s., 42, 4 V peak, or 60 V d. c.
b) The current that can appear in the circuit is limited by one of the following m eans:
I EC 62052-31 :201 5 © I EC 201 5
1)
– 1 27 –
th e m a xim um a va ila b le curre n t is lim ite d in h e re n tly or b y im p e da n ce s o th a t it ca n n o t
e xce e d th e a p p lica b le va lue of Ta b le 29 ;
2)
curre n t
is
lim ite d
by a n
ove rcurre n t
p rote ction
de vice
so
th a t
it
ca n n ot
e xce e d
th e
a p p lica b le va lue s o f Ta b le 30;
3)
a re gula tin g n e two rk lim its th e m a xim um a va ila b le curre n t s o th a t it ca n n o t e xce e d th e
re le va n t va lue of Ta b le 29 in n o rm a l co n ditio n o r a s a re sult o f a fa ult in th e re gula tin g
n e twork.
c) I t is separated by at least basic insulation from other circuits having energy values
exceeding criteria a) and b) above.
I f an overcurrent protection device is used, it shall be a fuse or a non-adjustable non-selfresetting electromechanical device.
Co n form ity is ch e cke d b y in s p e ctio n a n d b y m e a surin g th e p o te n tia ls a p p e a rin g in th e circuit
a n d th e m a xim um a va ila b le curre n t, un de r th e fo llowin g co n dition s:
i)
th e p o te n tia ls a p p e a rin g in th e circuit a re m e a sure d in th e loa d co n ditio n th a t m a xim ize s
th e vo lta ge ;
ii)
outp ut curre n t is m e a s ure d a fte r 60 s o f o p e ra tio n ,
with th e re s istive lo a d (in cludin g sh ort
circuit) wh ich p ro duce s th e h igh e st va lue o f curre n t.
Table 29 – Limits of maximum available current
Open-circui t output vol tage ( U or Û)
Maximum available current
V
a
A
a
a. c. r. m .s. or d. c.
a. c. r. m .s.
d. c.
Peak
U≤ 2
2 < U ≤ 1 2, 5
1 2, 5 < U ≤ 1 8, 7
1 8, 7 < U ≤ 30
U≤ 2
2 < U ≤ 1 2, 5
1 2, 5 < U ≤ 1 8, 7
1 8, 7 < U ≤ 60
Û ≤ 2, 8
2, 8 < Û ≤ 1 7, 6
1 7, 6 < Û ≤ 26, 4
26, 4 < Û ≤ 42, 4
50
1 00 /
U
8
1 50 /
U
The peak value ( Û) appli es to non -sinusoidal a. c. and to d. c. with ri ppl e exceedin g 1 0 %, and is provid ed for
conveni ence. The r. m . s. value of the m axim um available current shall be determ ined as that val ue is rel ated
to heati ng.
Table 30 – Values for overcurrent protection devices
Current that the device
breaks after not more
than 1 20 s b, c
Potential appearing in the circuit ( U or Û)
V
a. c. r. m .s.
a
A
d. c.
U≤ 2
U≤ 2
2 < U ≤ 1 2, 5
2 < U ≤ 1 2, 5
1 2, 5 < U ≤ 1 8, 7
1 2, 5 < U ≤ 1 8, 7
1 8, 7 < U ≤ 30
1 8, 7 < U ≤ 60
The peak value ( Û) appli es to non -sinusoidal a. c. and to d. c.
Peak
a
Û ≤ 2, 8
2, 8 < Û ≤ 1 7, 6
1 7, 6 < Û ≤ 26, 4
26, 4 < Û ≤ 42, 4
a. c. r. m .s. or d. c.
62, 5
1 25 /
U
10
200 /
U
with ri ppl e exceedin g 1 0 %, and is provid ed for
conveni ence. The r. m . s. value of the m axim um available current shall be determ ined as that val ue is related
to heati ng.
b
The evalu ation is based on the specified tim e-current breaki n g characteristic of th e d evice, which is different
from the rated breaking cu rrent. (For exam ple, an ANSI /UL 248-1 4 5 A fuse is specified to break 1 0 A at
1 20 s or less and an I EC 601 27 T-type 4 A fuse is specifi ed to break at 8, 4 A at 1 20 s or less. )
c
The breaking current of fuses is depen dent on tem perature, and this has to be taken into accou nt if the
tem peratu re im m ediately aroun d the fuse is significantl y hig her than the room tem peratu re.
– 1 28 –
9.5
I EC 62052-31 :201 5 © I EC 201 5
Overcurrent protection
NOTE 1 This subclause is based on I EC 61 01 0-1 : 201 0, 9. 6. 2.
As this standard applies onl y to permanentl y connected metering equipm ent, the use of
internal overcurrent protection elem ents such as fuses is optional.
NOTE 2 For functional reasons, they are gen erall y not used.
Overcurrent protection of metering equipment is provided by the overcurrent protection of the
installation. See also 5. 4. 5. 2.
1 0 Equipment temperature limits and resistance to heat
1 0.1 Surface temperature limits for protection against bu rns
NOTE This subcl ause is based on I EC 61 01 0-1 : 201 0, 1 0. 1 .
At an am bient temperature of 40 °C, the temperature of easil y touched surfaces shall not
exceed:
a) the values of Table 31 in normal condition; and
b) 1 05 °C in single fault condition, or when the EU T is exposed to the maxim um overload
current Iovl as agreed by the manufacturer and the purchaser.
At am bient temperatures exceeding 40 °C, easil y touched surfaces of equipm ent rated for a
maximum am bient temperature above 40 °C are perm itted to exceed:
c) the values of Table 31 in normal condition; and
d) 1 05 °C in single fault condition, or when the EU T is exposed to the m axim um overload
current Iovl as agreed by the manufacturer and the purchaser,
by not m ore than the am ount by which the m axim um rated ambient tem perature exceeds
40 °C.
Exam ple: I f the m axim um rated tem peratu re of equi pm ent is 55 °C, then th e surface tem perature lim it of easily
touched plastic parts in n orm al condition is:
a) 85 °C at an am bient tem peratu re of 40 °C, from Table 31 ;
b) 85 °C + (55 ° C – 40 °C) = 1 00 °C at an am bient tem perature of 55 °C.
Surfaces of the terminal blocks covered by terminal covers or, in the case of panel mounted
meters, protected by a barrier are not considered to be easily touched surfaces.
I EC 62052-31 :201 5 © I EC 201 5
– 1 29 –
Table 31 – Surface temperature limits in normal condition
Part
1)
Limit
°C
Outer su rface of enclosu re (u ni ntenti onal contact)
a) m etal, uncoated or anodi zed
65
b) m etal, coated (paint, n on -m etallic)
80
c)
85
plastics
d) glass and ceram ics
e) sm all areas ( < 2
cm 2 )
80
that are n ot likely to be touched in n orm al use
1 00
2) Knobs and handl es (n ormal use contact)
a) m etal
55
b) plastics
70
c)
65
glass and ceram ics
d) non -m etallic parts that in n orm al use are h eld onl y for short peri ods (1 s – 4 s)
NOTE 1
70
EN 563 and CENELEC Guide 29 provide i nform ation about the effect of the du rati on of contact.
NOTE 2 For an exam ple of evaluati ng test results, see 1 0. 4.
Conformity is checked by measurement as specified in 1 0. 4.
1 0.2 Temperature limits for terminals
At an am bient temperature of 40 °C the temperature of terminals shall not exceed:
a) the values of Table 32 in normal condition; and
b) 1 35 °C in single fault condition, or when the EU T is exposed to the maximum overload
current Iovl as agreed by the manufacturer and the purchaser.
At am bient tem peratures exceeding 40 °C, the temperature of terminals is permitted to
exceed:
c) the values of Table 32 in normal condition; and
d) 1 35 °C in single fault condition, or when the EU T is exposed to the m axim um overload
current Iovl as agreed by the manufacturer and the purchaser,
by not m ore than the amount by which the m axim um rated am bient temperature exceeds
40 °C.
Exam ple: I f the m axim um rated tem peratu re is 55 ° C, then the tem peratu re lim it of bare copper term inals is:
a) 1 00 ° C at an am bient tem perature of 40 °C from Table 32;
b) 1 00 ° C + (55 °C – 40 ° C) = 1 1 5 °C at an am bient tem perature of 55 °C.
– 1 30 –
I EC 62052-31 :201 5 © I EC 201 5
Table 32 – Temperature limits for terminals
Terminal material
Temperature limits
°C a
Bare copper
1 00
Bare brass
1 05
Tin plated copper or brass
1 05
Sil ver pl ated or nickel plated copper or brass
110
Other m etals
b
a
The use in service of conn ected cond uctors significantly smaller than th ose l isted in Tabl e 1 could result i n
high er term inals an d i nternal part tem peratu res and such cond uctors sh oul d not be u sed without th e
m anufacturer’s consent since h igher tem peratures could l ead to eq uipm ent failu re.
b
Tem peratu re lim its to be based on service experi ence or life tests but not to exceed 1 05 °C.
NOTE This table is based on I EC 60947-1 : 2007, Table 2, by addi ng 40 °C to the temperatu re rise lim its
specified i n that table.
Co n form ity is ch e cke d b y m e a sure m e n t a s s p e cifie d in 1 0. 4 .
1 0.3 Temperatures of internal parts
NOTE This subcl ause is based on I EC 62477-1 : 201 2, 4. 6. 4. 1 .
The components, parts and m aterials of the equipm ent shall not attain tem peratures in excess
of those in Table 33 when the equipment is operated in accordance with its ratings.
The equipment shall be is tested in worst case conditions, appl ying the m axim um current Im ax
or, when agreed by the manufacturer and the purchaser the m axim um overload current Iovl
and the maxim um rated voltage, with all optional accessories attached.
The m aximum m easured tem peratures shall be corrected by adding the difference between
the am bient temperature during the test and th e rated m aximum ambient temperature of the
equipment.
Co m p lia n ce is ch e cke d b y th e te st of sub cla us e 1 0. 4.
I EC 62052-31 :201 5 © I EC 201 5
– 1 31 –
Table 33 – M axi m u m m easu red total tem peratu res
for i n tern al m ateri al s an d com pon en ts
M ateri al s an d com pon en ts
Th erm ocou pl e
m eth od
Ri se of resi stan ce
m eth od
°C
°C
a
1
Rubber- or therm oplastic-i nsul ated con ductors
2
Copper bus bars and con nectin g straps
3
I nsulation system s on m agnetic com ponents (win din gs)
75
b
Cl ass of insul ation (See I EC 60085)
d
c
d
Single
fault
Norm al
Single
faul t
Norm al
condition
condition
Cl ass A (1 05)
90
1 35
1 00
1 45
Cl ass E (1 20)
1 05
1 50
115
1 60
Cl ass B (1 30)
110
1 55
1 20
1 65
Cl ass F (1 55)
1 30
1 65
1 40
1 75
1 55
1 85
1 65
1 95
Cl ass H (1 80)
a
1 65
4
Phenolic com position
5
On bare resistor m aterial
6
Capacitor
e
7
Power electron ic devices
f
8
PWBs
g
9
Com ponents bri dgi ng at l east basic protection
e
41 5
e
1 0 Batteries
a
The lim itation on rubber and th erm oplastic insul ation an d ph enolic com position does n ot apply to com pounds
which h ave been i nvestigated and foun d to m eet the requi rem ents for a high er tem peratu re.
b
The m axim um perm itted tem peratu re is d eterm ined by th e tem perature lim it of support m ateri als or i nsulati on
of connecti ng wi res or oth er com ponents. A m axim um tem perature of 1 40 °C is recomm ended.
c
The m axim um tem peratu res on insulati on of m agnetic com pon ents assum e therm ocouples are applied on th e
surface of coils, an d are th erefore not located on hot-spots. Rise of resistance m ethod results in a
m easurem ent of the average tem perature of th e win din g.
d
These l im its are extracted from the group safety standards I EC 61 558-1 an d I EC 61 558-2-1 6 (Safety of
power transform ers, power su pplies, reactors and sim ilar prod ucts).
e
For a com pon ent, the m axim u m tem perature specified by the m anufacturer shou ld n ot be exceeded.
f
The m axim um tem peratu re on the case should be the m axi m um case tem perature for th e appl ied power
dissipation specified by the m anufactu rer of power el ectronic devices.
g
The m axim um operatin g tem perature of th e PWB shall not be exceeded.
To determ ine the tem perature rise of a winding by the change of resistance method the
following form ula shall be used.
∆푡
where:
∆ 푡 is the
푅 2 is the
푅1 is the
푡1 is the
푡2 is the
= 푅2푅−푅1 1 (푘 + 푡1 ) − (푡2 − 푡1 )
tem perature rise above 푡2 so that the maximum temperature equals to
resistance at the end of the test, in Ω ;
resistance at the beginning of the test, in Ω ;
am bient temperature at the beginning of the test, in ºC;
ambient temperature at the end of the test, in ºC;
∆푡 +
푡2
;
– 1 32 –
푘
I EC 62052-31 :201 5 © I EC 201 5
is 234, 5 for copper, 225, 0 for electrical conductor grade (EC) alum inium. Values of the
constant for other conductors shall be determined.
1 0. 4
Tem peratu re test
NOTE This subclause is based on I EC 62477-1 : 201 2, 5. 2. 3. 1 0 as well as on I EC 62052-1 1 : 2003, 7. 2 an d
I EC 62052-21 : 2004, 7. 2.
The test is intended to ensure that accessible surfaces and parts of the metering equipment
do not exceed the temperature limits specified in subclauses 10. 1, 10. 2 and 10.3 and that the
manufacturer’s temperature limits of safety-relevant parts are not exceeded.
It is allowed to use a new metering equipment for the test.
Equipment shall be tested built in as specified in the installation instructions, using walls of
plywood painted matt black, approximately 10 mm thick when representing the walls of a
cabinet, approximately 20 mm thick when representing the walls of a building. The connecting
cables shall be as specified in 4. 3. 2. 11.
The test shall be performed under reference conditions specified in 4.3.1, with ambient
temperature 23 °C ± 2 °C at the start of the test with each voltage circuit (and with those
auxiliary voltage circuits which are energized for periods of longer duration than their thermal
time constants) carrying 1, 15 times the reference voltage and:
a) in the case of single phase two-wire meters, both the phase and the neutral conductor
carrying rated maximum current;
b) in the case of single-phase three-wire meters:
1) each current circuit carrying rated maximum current with the neutral conductor not
carrying current;
2) one phase and the neutral conductor carrying rated maximum current;
c) in the case of three-phase three-wire meters each current circuit carrying rated maximum
current;
d) in the case of three-phase four-wire meters:
1) each current circuit carrying rated maximum current with the neutral conductor not
carrying current;
2) the current circuit closest to the neutral terminal and the neutral terminal carrying rated
maximum current;
e) in the case of tariff and load control equipment, energized with 1,15 times the reference
voltage and carrying maximum total current.
For test with polyphase currents, current shall be balanced in each phase within ± 5 % and the
average of these currents shall be not less than the appropriate test current.
The test shall be maintained until thermal stabilization has been reached. That is, when three
successive readings, taken at intervals of 10 % of the previously elapsed duration of the test
and not less than 10 min intervals, indicate no change in temperature, defined as ± 1 °C
between any of the three successive readings, with respect to the ambient temperature.
If a heat source could cause the failure of insulation at a certain point leading to a hazard, the
temperature of the electrical insulation (other than that of windings) is measured on the
surface of the insulation at the closest point to the heat source.
If temperatures of windings are measured by the thermocouple method, the thermocouple
shall be located on the surface of the winding located at the hottest part due to surrounding
heat emitting components. See also notes in Table 33.
I EC 62052-31 :201 5 © I EC 201 5
Th e
m a xim um
te m p e ra ture
te m p e ra ture
of
th e
– 1 33 –
a tta in e d
m e te rin g
s h a ll
e quip m e n t
be
by
corre cte d
a ddin g
th e
to
th e
ra te d
diffe re n ce
m a xim um
b e twe e n
th e
a m b ie n t
a m b ie n t
te m p e ra ture a tta in e d durin g th e te s t a n d th e ra te d m a xim um a m b ie n t te m p e ra ture .
No corre cte d te m p e ra ture s h a ll e xce e d th e
ra te d te m p e ra ture o f th e
m a te ria l or co m p o n e n t
me a sure d.
EXAMPLE 1
The rated m axim um am bient tem peratu re is 40 °C. Th e m eter case is m ade of pl astic. The am bient tem perature
attain ed d uring the test is 32 ° C. The m axim um tem peratu re m easured on th e m eter case i s 64 °C. Th e corrected
tem peratu re is 64 + (40-32) = 72 °C. This is below 85 ° C, the lim it specified in Tabl e 31 . The m eter passed.
EXAMPLE 2
The rated m axim um am bient tem peratu re is 55 ° C. Th e m eter case is m ade of pl astic. Th e am bient tem perature
attained d uring the test is 32 ° C. The m axim um tem perature m easured on th e m eter case i s 64 °C. The corrected
tem peratu re is 64 + (55-32) = 87 °C.
The tem perature lim it based on Tabl e 31 scaled to the m axi m um rated tem perature is 85+(55-40) = 1 00 ° C. The
m eter passed.
EXAMPLE 3
The rated m axim um am bient tem peratu re is 55 ° C. Th e m eter case is m ade of pl astic. Th e am bient tem perature
attained d uring the test is 32 ° C. The m axim um tem perature m easured on th e m eter case i s 79 °C. The corrected
tem peratu re is 79 + (55-32) = 1 02 ° C.
The tem perature lim it based on Tabl e 31 scaled to the m axi m um rated tem perature is 85+(55-40) = 1 00 ° C. The
m eter failed.
Wh e n
th e
m a n ufa cture r a n d
th e
p urch a se r a gre e d
m a xim um ove rlo a d curre n t
Iovl ,
sp e cim e n ,
ca rryin g
with
th e
m a xim um curre n t.
m e te r
Th e
se e
3. 3. 1 1 ,
th e
th a t
th e
m e te r m a y
be
e xp os e d
th e te st sh a ll a ls o b e ca rrie d out on
m a xim um
te st dura tio n sh a ll b e 2 h .
ove rlo a d
curre n t
a gre e d
to
th e
a n e w te st
in s te a d
of
th e
A ll oth e r co n ditio n s sh a ll b e th e s a m e a s
durin g th e te st with th e m a xim um curre n t.
Th e
m a xim um
te m p e ra ture
te m p e ra ture
of
th e
a tta in e d
m e te rin g
sh a ll
e q uip m e n t
be
by
corre cte d
a ddin g
th e
to
th e
ra te d
diffe re n ce
m a xim um
b e twe e n
th e
a m b ie n t
a m b ie n t
te m p e ra ture a tta in e d durin g th e te s t a n d th e ra te d m a xim um a m b ie n t te m p e ra ture .
Th e corre cte d te m p e ra ture o f e a sily to uch e d surfa ce sh a ll n ot e xce e d 1 05 °C, th e te m p e ra ture
of
te rm in a ls
s h a ll
not
e xce e d
1 35
°C
and
th e
te m p e ra ture
of
in te rn a l
m a te ria ls
and
com p on e n ts s h a ll n ot e xce e d th e va lue s sp e cifie d in Ta b le 33.
1 0. 5
1 0. 5. 1
Resi stan ce to h eat
N on -m etal l i c en cl osu res
NOTE This subcl ause is based in I EC 61 01 0-1 : 201 0, 1 0. 5. 2.
Enclosures of non-metallic m aterial shall be resistant to elevated tem peratures.
Co n fo rm ity is ch e cke d b y te st, a fte r on e o f th e fo llowin g tre a tm e n ts .
a)
A
n o n -op e ra tive
70 °C
±
tre a tm e n t,
2 °C, or a t 1 0 °C
±
in
wh ich
th e
e q uip m e n t,
n ot e n e rgize d,
is
s tore d for 7 h
at
2 °C a b ove th e te m p e ra ture m e a s ure d durin g th e te s t of 1 0. 4 ,
wh ich e ve r is h igh e r. If th e e q uip m e n t con ta in s co m p o n e n ts th a t m igh t b e da m a ge d b y th is
tre a tm e n t, a n e m p ty e n closure m a y b e tre a te d, fo llo we d b y a sse m b ly o f th e e q uip m e n t a t
th e e n d o f th e tre a tm e n t.
b)
An
o p e ra tive
tre a tm e n t,
con ditio n s o f 4. 3,
a b ove
th e
m a xim um
sp e cifie d in 1 0. 4.
in
wh ich
e xce p t th a t th e
ra te d
th e
e quip m e n t
is
o p e ra te d
a m b ie n t te m p e ra ture
a m b ie n t
te m p e ra ture
if
is
un de r
20 °C
h igh e r
th a n
±
th e
re fe re n ce
2 °C a b ove
4 0 °C,
and
te s t
4 0 °C,
or
lo a de d
as
– 1 34 –
I EC 62052-31 :201 5 © I EC 201 5
Within 1 0 min of the end of treatment the equipm ent shall be su bj ected to the stress specified
in 8. 2, and meet the pass criteria of 8. 1 .
1 0 . 5. 2
I n s u l ati n g
m a t e ri a l s
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, 1 0. 5. 3 an d I EC 62052-1 1 : 2003, 5. 4, with alternati ve test
m ethods add ed.
I nsulating materials supporting the mains terminals and the contacts of suppl y and/or load
control switches shall have adequate resistance to heat.
Conformity is checked by inspection of data on materials, and in case of doubt by performing
one of the following tests.
a) The deflection temperature test (ISO 75-2)
The insulating material shall be capable of passing the test given in ISO 75-2 for a
temperature of 124 °C and a pressure of 1,8 MPa (method A).
b) The ball pressure test (IEC 60695-10-2)
A sample of the insulating material, at least 2, 5 mm thick, is subjected to a ball-pressure
test using the test apparatus shown in Figure 12. The test is made at 125 °C ± 2 °C. The
part to be tested is supported so that its upper surface is horizontal, and the spherical part
of the apparatus is pressed against this surface with a force of 20 N. After 1 h the
apparatus is removed and the sample is cooled within 10 s to approximately room
temperature by immersion in cold water. The diameter of the impression caused by the
ball shall not exceed 2 mm.
NOTE 2 I f necessary, the req uired thickness m ay be obtai ned by using two or m ore section s of the part.
NOTE 3 For suppl y and l oad control switch es, onl y those parts that support or retain the contacts in position are
subjected to the test.
1
2
3
IEC
Ke y
1
2
3
Part to be tested
Spherical part of the apparatus (diam eter 5 mm )
Support
F i g u re 1 2 – B a l l - p re s s u re t e s t a p p a ra t u s
c) The Vicat softening test (I SO 306 )
Method A120 using a force of 10 N and a heating rate of 120 °C/h. The Vicat softening
temperature shall be at least 130 °C.
1 1
P ro t e c t i o n a g a i n s t p e n e t ra t i o n o f d u s t a n d w a t e r
NOTE 1 This subclause is based on I EC 62052-1 1 : 2003, 5. 9.
Metering equipment shall conform to the following degree of protection given in
I EC 60529: 1 989:
•
indoor meters I P51 ;
I EC 62052-31 :201 5 © I EC 201 5
– 1 35 –
NOTE 2 Meters eq uipped with physical paym ent token carri ers acceptors are for i n door use onl y, unl ess
otherwise specified by th e m anufacturer.
•
outdoor meter: I P54.
For panel m ounted meters, where the panel provides I P protection, the I P ratings appl y to the
meter parts exposed in front of (outside of) the electrical panel.
NOTE 3 M eter parts beh ind the panel m ay have lower I P rating, e. g. I P30.
The enclosure shall be treated as:
•
category 2 in the case of indoor meters;
NOTE 4 Categ ory 2 enclosu res are enclosu res where no pressure difference relati ve to the surround ing air is
present.
•
category 2 or category 1 in the case of outdoor m eters according to the documentation
provided by the m anufacturer.
NOTE 5 Category 1 enclosures are enclosu res wh ere the norm al working cycle of the equi pm ent causes
red uctions in air pressu re within the enclosu re bel ow th at of the surround ing air, for exam ple, due to th erm al
cycling effects.
Conformity is checked with the following tests:
a) Dust test for first characteristic numeral 5, according to IEC 60529:1989, 13. 4:
•
meter in non-operating condition and installed according to the manufacturer’s
instructions, including all terminal covers provided;
•
with sample lengths of cable (exposed ends sealed) of the type specified by the
manufacturer and with the terminal cover(s) in place;
•
meters equipped with physical payment token acceptors shall be tested without any
token carrier in place in the token carrier acceptor;
•
metering equipment with category 2 enclosures shall not be connected to a vacuum
pump.
The protection is satisfactory if, on inspection, talcum powder has not accumulated in a
quantity or location such that, as with any other kind of dust, it could interfere with the correct
operation of the equipment or impair safety. No dust shall deposit where it could lead to
tracking along the creepage distances.
Care should be taken during the inspection to avoid accidental transfer of the talcum powder
to locations where its accumulation could be interpreted as a test failure.
b) Protection against penetration of water
•
meter in the same conditions as for test a)
•
test for second characteristic numeral 1 (IPX1) for indoor meters as specified in
IEC 60529:1989, 14. 2. 1 with drip box;
•
test for second characteristic numeral 4 (IPX4) for outdoor meters as specified in
IEC 60529:1989, 14. 2. 4, with oscillating tube.
After testing the enclosure shall be inspected for ingress of water. If any water has entered, it
shall not:
•
•
•
•
be sufficient to interfere with the correct operation of the equipment or impair safety;
deposit on insulation parts where it could lead to tracking along the creepage distances;
reach live parts or windings not designed to operate when wet;
accumulate near the cable ends or enter the cables.
In addition, the AC power-frequency voltage test as specified in 6. 10. 4. 3. 4 shall be passed.
– 1 36 –
I EC 62052-31 :201 5 © I EC 201 5
1 2 Protection against liberated gases and substances explosion and implosion
– Batteries and battery charging
NOTE This clause is based on I EC 61 01 0-1 : 201 0, 1 1 . 5 an d 1 3. 2. 2 as well as on I EC 60255-27: 201 3, 8. 7. 2. 2.
Batteries shall be so m ounted that safety cannot be impaired by leakage of their electrolyte.
Co n fo rm ity is ch e cke d b y in s p e ctio n .
Batteries shall not cause explosion or produce a fire hazard as a result of excessive charge or
discharge, or if a battery is installed with incorrect polarity. I f necessary, protection shall be
incorporated in the equipment, unless the m anufacturer's instructions specify that it is for use
onl y with batteries which have built-in protection. See Annex J for examples of battery
protection.
I f an explosion or fire hazard could occur through fitting a battery of the wrong type (for
example, if a battery with built-in protection is specified) there shall be a warning m arking
(see 5.2. 1 ) on or near the battery com partment or m ounting, and a warning in the
m anufacturer's instructions. An acceptable m arkin g is symbol 1 4 of Table 3. See also 5. 4.8.
I f equipm ent has means for charging rechargeable batteries, and if non -rechargeable cells
could be fitted and connected in the battery compartment, there shall be a warning marking
(see 5. 2. 1 ) in or near the com partment. The m arking shall warn against the charging of nonrechargeable batteries and indicate the type of rechargeable battery that can be used with the
recharging circuit. An acceptable m arking is symbol 1 4 of Table 3.
Non-rechargeable batteries used in the equipment should be protected against accidental
charging in norm al and single fault conditions.
The battery com partment shall be designed so that there is no possibility of explosion or fire
caused by build-up of flamm able gases.
For batteries intended to be replaced by the user, if an attem pt is made to install a battery
with its polarity reversed, no hazard shall arise.
Co n form ity is
ch e cke d b y in s p e ction ,
in cludin g
in sp e ctio n
o f b a tte ry da ta ,
to
e sta b lis h
th a t
fa ilure of a s in gle co m p o n e n t ca n n ot le a d to a n e xp los io n or fire h a za rd. If n e ce ssa ry, a sh ort
circuit a n d a n op e n circuit is m a de o n a n y sin gle co m p on e n t (e xce p t th e b a tte ry its e lf) wh os e
fa ilure co uld le a d to such a h a za rd.
For b a tte rie s in te n de d to b e re p la ce d b y a n o p e ra tor,
a n a tte m p t is m a de to in s ta ll a b a tte ry
with its p o la rity re ve rse d. No h a za rd sh a ll a rise .
1 3 Components and sub-assemblies
1 3.1 General
NOTE 1 This subcl ause reproduces – m utatis m utandis – I EC 61 01 0-1 : 201 0, 1 4. 1 .
Connection of an y accessories or modules, such as communication modules, input/output
modules, external measuring transform ers, etc. , shall not reduce the safety of the equipm ent.
Com ponents, sub-assemblies, accessories or modules which are essential to the safety of the
equipm ent, shall conform to one of the following:
a) applicable safety requirements of a relevant I EC standard. Conformity with other
requirements of the com ponent standard is not required. I f necessary for the application,
com ponents shall be subj ected to the tests of this standard, except that it is not necessary
I EC 62052-31 :201 5 © I EC 201 5
– 1 37 –
to carry out identical or equivalent tests alread y perform ed to check conformity with the
com ponent standard;
NOTE 2 For exam ple if com ponents m eet the safety requi rem ents of I EC 60950-1 : 2005 but are rated for a
less severe en vi ronm ent than the applicable envi ronm ent of 1 . 4, they also n eed to m eet rel evant ad ditional
requirem ents of this standard.
b) the requirements of this standard and, where necessary for the application, an y additional
applicable safety requirem ents of the relevant I EC com ponent standard;
c) if there is no relevant I EC standard, the requirem ents of this standard;
d) applicable safety requirements of a non-I EC standard which are at least as high as those
of the relevant I EC standard, provided that the component has been approved to the non I EC standard by a recognized testing authority.
NOTE 3 Tests perform ed by a recog ni zed testin g authority which confi rm conform ity with applicable safety
req uirem ents need not be repeated even if the tests were perform ed usin g a n on-I EC stand ard.
Figure 1 3 is a flow chart showing m ethods of conform ity verification.
Conformity is checked by inspection and, if necessary, by test.
IEC
Fig u re 1 3 – Fl ow ch art for con form ity option s 1 3. 1 a) , b), c) an d d )
– 1 38 –
I EC 62052-31 :201 5 © I EC 201 5
1 3.2 Mains transformers tested outside equipment
NOTE This subcl ause reprod uces – m utatis m utandis – I EC 61 01 0-1 : 201 0, 1 4. 6.
I f environmental conditions could affect the test results, transformers tested outside the
equipm ent (see 4. 4. 2. 4) shall be tested in the same conditions as exist inside the equipm ent.
Conformity is checked by the relevant tests specified in 4. 4. 2. 4.2, 4. 4.2. 4. 3, 4. 4. 2. 4. 4, and
followed by the test of 4.4.4. 1 b) and c). If there is any doubt whether a transformer would
pass the other tests specified in 4.4. 4 and 10. 2 when installed in the equipment, the tests are
repeated with the transformer installed in the equipment.
1 3.3 Printed wiring boards
NOTE This subcl ause reprod uces I EC 61 01 0-1 : 201 0, 1 4. 7.
Printed wiring boards shall be m ade of material with a flammability classification of V-1 of
I EC 60695-1 1 -1 0 or better.
This requirem ent does not appl y to printed wiring boards which contain onl y limited-energ y
circuits meeting the requirements of 9. 4.
Conformity of the flammability rating is checked by inspection of data on the materials.
Alternatively, conformity is checked by performing the vertical burn tests of IEC 60695-11-10
on three samples of the relevant parts. The samples may be complete boards, sections of the
boards or specimens as specified in IEC 60695-11-10.
1 3.4 Components bridging insulation
NOTE This subcl ause has been taken from I EC 62477-1 : 201 2, 4. 4. 7. 1 . 7.
Com ponents bridging insulation shall com pl y with the requirements of the level of insulation
(e. g. basic, reinforced or double) they are bridging.
1 3.5 Circuits or components used as transient overvoltage limiting devices
NOTE 1 This subcl ause is based on I EC 61 01 0-1 : 201 0, Clause K. 4.
Transient overvoltages in a circuit m ay be lim ited by com binations of circuits or com ponents.
Com ponents suitable for this purpose include varistors and gas-filled surge arrestors.
NOTE 2 I EC 61 643-1 2 provi des inform ation on the sel ection and application princi ples of surg e protecti ve
devices.
I f the overvoltage limiting device or circuit is intended to reduce transient overvoltages so that
the circuit following it may have reduced clearances, a risk assessm ent (see Clause 1 5) shall
be perform ed, taking into account both of the following aspects:
a) No hazard shall arise in the event that the com ponent ruptures or overheats during the
test. I f a rupture occurs, no part of the com ponent shall bridge safety-relevant insulation. I f
the com ponent overheats, it shall not heat other m aterials to their self-ignition points.
Tripping of the protection during the test specified in 6. 1 0. 3. 4 is an indication of failure.
b) the circuit shall operate as intended even after withstanding repeated transient
overvoltages.
Conformity is checked by evaluation of the risk assessment documentation to ensure that the
risks have been eliminated or that only tolerable risks remain.
1 4 Hazards resulting from application – Reasonably foreseeable misuse
NOTE This clause reproduces I EC 61 01 0-1 : 201 0, 1 6. 1 .
I EC 62052-31 :201 5 © I EC 201 5
– 1 39 –
No hazards shall arise if adj ustments, knobs, or other controls are set in a way not intended,
and not described in the instructions. Other possible cases of reasonably foreseeable misuse
that are not addressed by specific requirem ents in this standard shall be addressed by risk
assessm ent (see Clause 1 5).
Co n fo rm ity
is
ch e cke d
by
in s p e ctio n
and
by
e va lua tion
of
th e
RISK
a ss e ss m e n t
docum e n ta tio n .
1 5 Risk assessment
NOTE 1 This clause reproduces I EC 61 01 0-1 : 201 0 Clause 1 7.
I f examination of the equipm ent shows that hazards not full y addressed in Clauses 6 to 1 4
(see 1 .2.1 ) might arise, then risk assessm ent is required. I t shall be carried out and
documented to achieve at least a tolerable risk by an iterative process covering the following.
a) Risk analysis
Risk anal ysis is the process to identify hazards and to estimate the risk based on the use
of available inform ation.
b) Risk evaluation
Each risk analysis requires a plan to evaluate the estimated severity and likelihood of a
risk, and to j udge the acceptability of the resulting risk level.
c) Risk reduction
I f the initial risk level is not acceptable, steps shal l be taken to reduce the risk. The
process of risk anal ysis and risk evaluation shall then be repeated, including checking that
no new risks have been introduced.
Risks remaining after a risk assessm ent shall be identified in the instructions for the installer,
operator, user and service personnel. Adequate inform ation about how to mitigate these risks
shall be given.
In selecting the m ost appropriate methods of risk reduction, the m anufacturer shall appl y the
following principles, in the order given:
1 ) eliminate or reduce risks as far as possible (an inherentl y safe design and construction);
2) take the necessary protective m easures in relation to risks that cannot be elim inated;
3) inform users of the residual risks due to an y shortcomings of the protective measures
adopted, indicate whether an y particular training is required, and specify an y need to
provide personal protective equipm ent.
NOTE 2 One risk assessm ent proced ure is outli ned in Annex J of I EC 61 01 0-1 : 201 0. Other risk assessm ent
procedu res are contain ed i n I SO 1 4971 , SEMI S1 0-1 296, I EC 61 508, I SO 1 41 21 -1 , and ANSI B1 1 . TR3. Oth er
establish ed procedu res wh ich i m plem ent sim ilar steps can also be used.
Co n form ity is ch e cke d b y e va lua tio n o f th e risk a s se ssm e n t do cum e n ta tio n to e n s ure th a t th e
risks h a ve b e e n e lim in a te d or th a t o n ly to le ra b le risks re m a in .
– 1 40 –
I EC 62052-31 :201 5 © I EC 201 5
An n ex A
(normative)
M eas u ri n g ci rcu i ts for tou ch cu rren t
A. 1
M easu ri n g ci rcu i t for a. c. wi th freq u en ci es u p to 1 M H z an d for d . c.
NOTE 1 This Ann ex A reprod uces I EC 61 01 0-1 : 201 0, Annex A.
NOTE 2 I t is based on I EC 60990, which specifies procedu res for m easuri ng touch -current, and also specifi es the
characteristics for test voltm eters.
NOTE 3 Frequency d epend ence of electric shocks is being investigated by TC 64 an d depend ing on the result
changes in this area m ay be requi red.
The current is m easured using the circuit of Figure A. 1 . The current is calculated from :
퐼
푈
= 500
where
I
is the current, in A;
U is the voltage, in V, indicated by the voltm eter.
This circuit represents the impedance of the bod y and com pensates for the change of
ph ysiological response of the bod y with frequency.
R1
C1
R3
R2
C2
V
IEC
Ke y
R1 = 1 500 Ω with a relati ve tol erance of ± 5 %
R2 = 500 Ω with a rel ati ve tol erance of ± 5 %
R3 = 1 0 k Ω with a relati ve tolerance of ± 5 %
C1 = 0, 22 µ F with a relati ve tol erance of ± 1 0 %
C2 = 0, 022 µ F with a relati ve tolerance of ± 1 0 %
F i g u re A. 1 – M e as u ri n g ci rcu i t fo r a. c. wi th fre q u en ci e s u p to 1 M H z an d fo r d . c.
I EC 62052-31 :201 5 © I EC 201 5
A.2
– 1 41 –
Measuring circuits for sinusoidal a.c. with frequencies up to 1 00 Hz and
for d.c.
I f the frequency does not exceed 1 00 H z, the current m ay be measured using either of the
circuits of Figure A. 2. When using the voltm eter, the current is calculated from :
푈
= 2000
퐼
where
I
is the current, in A;
U is the voltage, in V, indicated by the voltm eter.
The circuit represents the impedance of the bod y for frequencies not exceeding 1 00 H z.
NOTE The val ue 2 000 Ω incl udes the im pedance of the m easuri ng instrum ent.
R
R
V
A
IEC
Key
R = 2 000 Ω with a relative tolerance of ± 5 %
Figure A.2 – Measuring circuits for sinusoidal a.c.
with frequencies up to 1 00 Hz and for d.c.
A.3
Current measuring circuit for electrical burns at high frequencies
The current is m easured using the circuit of Figure A. 3 . The current is calculated from:
퐼
푈
= 500
where
I
is the current, in A;
U is the voltage, in V, indicated by the voltm eter.
This circuit compensates for the effects of high frequency on the ph ysiological response of the
bod y.
– 1 42 –
I EC 62052-31 :201 5 © I EC 201 5
R1
C1
V
R2
IEC
Key
R1 = 1 500 Ω with a relati ve tol erance of ± 5 %
R2 = 500 Ω with a rel ati ve tol erance of ± 5 %
C1 = 0, 22 µ F with a relati ve tol erance of ± 1 0 %
Figure A.3 – Current measuring circuit for electrical burns
A.4
Current measuring circuit for wet location
For wet location the current is measured using the circuit of Figure A.4. The current is
calculated from:
퐼
푈
= 500
where
I
is the current, in A;
U is the voltage, in V, indicated by the voltm eter.
R1
C1
R2
V
IEC
Key
R1 = 375 Ω with a rel ati ve tol erance of ± 5 %
R2 = 500 Ω with a rel ati ve tol erance of ± 5 %
C1 = 0, 22 µ F with a relati ve tol erance of ± 1 0 %
Figure A.4 – Current measuring circuit for wet contact
I EC 62052-31 :201 5 © I EC 201 5
– 1 43 –
An n e x B
(informative)
E x a m p l e s fo r i n s u l a ti o n b e tw e e n p a rts
B. 1
I n s u l a t i o n b e tw e e n p a rt s – E x a m p l e 1
Figure B. 1 shows a meter with the HLV m ains terminals – the voltage and current terminals –
connected directly to the HLV mains circuit.
Double or reinforced insulation is applied between the HLV m ains circuit and the SELV circuit
as well as between the H LV mains circuit and the PELV circuit.
Basic insulation is applied between the H LV mains circuit and the ELV circuit as well as
between the H LV mains circuit and the PEB circuit with one pole of the PEB terminals
connected to protective earth.
IEC
1)
2)
3)
I f the case / accessibl e parts are conducti ve an d they are con nected to the protecti ve condu ctor term inal, onl y
basic insul ation is requi red between th ese and the m ains term inals / m ains circuit. Oth erwise, doubl e or
rei nforced insul ation is requi red.
I f the case is conductive, basic insulati on is requ ired between it an d th e n on -m ains circuit, S ELV, PELV, ELV
and PEB circuits. Otherwise, functional i nsul ation m ay be used.
The con nection path of the PEB circuit to the protecti ve cond uctor term inal, inclu din g i m pedance Z, shal l
com ply with 6. 5. 2. 4. Th en, if u nder a singl e fault con dition, an HLV cond uctor was sh orted to the PEB circu it,
the PEB circuit wou ld n ot becom e hazardous live.
F i g u re B . 1
– I n su l ati on
b e t w e e n p a rt s – E x a m p l e 1
To verify this design a test voltage for double / reinforced insulation has to be applied
between the HLV mains term inals and the SELV and PELV terminals.
I f a reinforced insulation is used this design can be verified in both normal and single fault
conditions using the black box test m ethod, provided that the ful l test voltage appears across
the insulation under test.
– 1 44 –
I EC 62052-31 :201 5 © I EC 201 5
I f a double insulation is used, this design can be verified onl y in norm al condition using the
black box test method provided that the full test voltage appears across the insulation under
test. H owever, design verification in single fault condition is not possible with the black box
test method. The double insulation consists of a layer of basic insulation and a layer of
supplementary insulation. I n single fault conditions each of these layers should be subjected
to fault (shorted), one at a tim e, and it should be verified that the rem aining intact insulation
layer still provides at least basic protection.
B. 2
I n s u l a t i o n b e tw e e n p a rt s – E x a m p l e 2
Figure B. 2 shows a meter with the HLV m ains term inals – the voltage and current terminals –
connected directl y to the HLV mains circuit.
Basic insulation is applied between the H LV mains circuit and the ELV circuit.
Supplem entary insulation is applied between the ELV circuit and the SELV circuit as well as
between the ELV circuit and the PELV circuit. With this, double insulation between the H LV
mains circuits and the SELV / PELV circuits is assured.
IEC
1)
2)
3)
4)
I f the case / accessibl e parts are conducti ve an d they are con nected to the protecti ve condu ctor term inal, onl y
basic insul ation is requi red between th ese and th e H LV m ain s term inals / m ains circuit. Oth erwise, doubl e or
rei nforced insul ation is requi red.
I f the case is con ducti ve, basi c insulation is req uired between it and th e SELV, PELV, ELV and PEB circuits.
Otherwise, fu nctional insul ation m ay be used.
The con nection path of the PEB circuit to the protecti ve cond uctor term inal, inclu din g i m pedance Z, shal l
com ply with 6. 5. 2. 4. Th en, if u nder a singl e fault con dition, an HLV cond uctor was shorted to the PEB circu it,
the PEB circuit wou ld n ot becom e hazardous live.
Function al insul ation is req ui red between the ELV circu it an d the PEB circuit, unless the circuits have to be
independent in which case basic or supplem entary i nsulati on shall be used.
F i g u re B . 2 – I n s u l a t i o n
b e t w e e n p a rt s – E x a m p l e 2
To verify this design, a test voltage for double or rei nforced insulation has to be applied
between the HLV mains term inals and the SELV and PELV term inals.
Verification of the basic insulation between the H LV m ains circuit and the ELV circuit on the
one hand, and verification of the supplem entary insulation between the ELV circuit and the
I EC 62052-31 :201 5 © I EC 201 5
– 1 45 –
PELV/SELV circuits on the other hand is not possible using a black box test m ethod as it is
not possible to ensure that the correct test voltage will be applied to each insulation layer.
Design verification in single fault condition is not possible either with the black box test
method. The double insulation consists of a layer of basic insulation and a layer of
supplementary insulation (in this exam ple equivalent to basic insulation). I n single fault
conditions each of these layers should be subjected to fault (shorted), one at a time, and it
should be verified that the rem aining, intact insulation layer still provides at least basic
protection.
B. 3
I n s u l a t i o n b e tw e e n p a rt s – E x a m p l e 3
Figure B. 3 shows a meter with HLV mains terminals – the voltage and current terminals –
insulated from the H LV non-m ains circuit by basic insulation.
Double or reinforced insulation is applied between the H LV non-m ains circuit and the SELV
circuit as well as between the HLV non-m ains circuit and the PELV circuit. With this, double
insulation between the H LV mains terminals and the SELV / PELV circuits is assured.
Basic insulation is applied between the H LV non-mains circuit and the ELV circuit as well as
between the H LV non-m ains circuit and the PEB circuit with one pole of the PEB term inals
connected to protective earth.
IEC
1)
2)
3)
I f the case / accessibl e parts are conducti ve an d they are con nected to the protecti ve condu ctor term inal, onl y
basic insul ation is requi red between th ese and th e H LV m ain s term inals / m ains circuit. Oth erwise, doubl e or
rei nforced insul ation is requi red.
I f the case is cond uctive, basi c insulation is req ui red between it and the non-m ains circui t, the SELV, and
PELV circuits. Otherwise, functional insul ation m ay be used.
The con nection path of the PEB circuit to the protecti ve cond uctor term inal, inclu din g i m pedance Z, shal l
com ply with 6. 5. 2. 4. Th en, if u nder a singl e fault con dition, an HLV cond uctor was shorted to the PEB circu it,
the PEB circuit wou ld n ot becom e hazardous live.
F i g u re B . 3 – I n s u l a t i o n
b e t w e e n p a rt s – E x a m p l e 3
To verify this design, a test voltage for double or reinforced insulation has to be applied
between the HLV mains term inals and the SELV and PELV terminals.
– 1 46 –
I EC 62052-31 :201 5 © I EC 201 5
I f a reinforced insulation is used this design can be verified in both norm al and single fault
conditions using the black box test method, provided that the full test voltage appears across
the insulation under test.
I f a double insulation is used, this design can be verified onl y in norm al condition using the
black box test method provided that the full test voltage appears across the insulation under
test. H owever, design verification in single fault condition is not possible with the black box
test method. The double insulation consists of a layer of basic insulation and a layer of
supplementary insulation. I n single fault conditions each of these layers should be subj ected
to fault (shorted), one at a tim e, and it should be verified that the rem aining intact insulation
layer still provides at least basic protection.
B. 4
I n s u l a t i o n b e tw e e n p a rt s – E x a m p l e 4
Figure B. 4 shows a meter with HLV mains terminals – the voltage and current terminals –
insulated from the ELV circuit by basic insulation.
Supplem entary insulation is applied between the ELV circuit and the SELV circuit as well as
between the ELV circuit and the PELV circuit. With this, double insulation between the H LV
mains terminals and the SELV / PELV circuits is assured.
The PEB circuit is connected directly to the m ains circuit with one pole of the PEB terminals
connected to protective earth.
IEC
1)
2)
3)
4)
I f the case / accessibl e parts are conducti ve an d they are con nected to the protecti ve condu ctor term inal, onl y
basic insulati on is requi red between these and th e HLV m ains term inals. Otherwise, d ouble or reinforced
insulati on is requi red.
I f the case is conductive, basic insulati on is requ ired between it an d th e n on -m ains circuit, SELV, PELV, ELV
and PEB term inal s. Otherwise, functional insul ation m ay be u sed.
The con nection path of th e PEB term inals to the protective cond uctor term inal, incl udi ng im ped ance Z, sh all
com ply with 6. 5. 2. 4. Th en, if un der a sin gle fau lt con dition, an HLV cond uctor was sh orted to th e PEB
term inals, the PEB term inals would not becom e hazardous live.
Function al insul ation is req ui red between the ELV circu it an d the PEB circuit, unless the circuits have to be
independent in which case basic or supplem entary i nsulati on shall be used.
F i g u re B . 4 – I n s u l a t i o n
b e t w e e n p a rt s – E x a m p l e 4
I EC 62052-31 :201 5 © I EC 201 5
– 1 47 –
To verify this design a test voltage for double / reinforced insulation test has to be applied
between the HLV m ains terminals and the SELV and PELV term inals.
Verification of the basic insulation between the H LV m ains term inals and the ELV circuit on
the one hand, and verification of the supplem entary insulation between the ELV circuit and
the PELV/SELV circuits on the other hand is not possible using a black box test method as it
is not possible to ensure that the correct test voltage will be applied to each insulation layer.
Design verification in single fault condition is not possible either with the black box test
method. The double insulation consists of a layer of basic insulation and a layer of
supplementary insulation (in this exam ple equivalent to basic insulation). I n single fault
conditions each of these layers should be subjected to fault (shorted), one at a tim e, and it
should be verified that the remaining, intact insulation layer still provides at least basic
protection.
B. 5
I n s u l a t i o n b e tw e e n p a rt s – E x a m p l e 5
Figure B. 5 shows a meter with three independent mains circuits:
The HLV mains terminals 1 are the voltage and current terminals connected directl y to
m ains circuit 1 .
•
The H LV m ains terminals 2 are auxiliary suppl y terminals connected directl y to mains
circuit 2.
•
The H LV m ains terminals 3 are the term inals of a load switch with independent terminals,
connected directl y to m ains circuit 3.
Basic insulation is applied between each mains circuit and the ELV circu it.
•
Supplem entary insulation is applied between the ELV circuit and the SELV circuit as well as
between the ELV circuit and the PELV circuit. With this, double insulation between the H LV
mains circuits and the SELV / PELV circuits is assured.
IEC
1)
2)
I f the case / accessibl e parts are conducti ve an d they are con nected to the protecti ve condu ctor term inal, onl y
basic insulati on is requi red between these and th e HLV m ains term inals. Otherwise, d ouble or reinforced
insulati on is requi red.
I f the case is cond uctive, basic insulati on is requ ired between it an d th e n on -m ains circuit, SELV, PELV, ELV
and PEB term inals. Otherwise, functional insul ation m ay be u sed.
F i g u re B . 5 – I n s u l a t i o n
b e t w e e n p a rt s – E x a m p l e 5
– 1 48 –
I EC 62052-31 :201 5 © I EC 201 5
To verify this design, a test voltage for double or reinforced insulation has to be applied
between the HLV m ains terminals and the SELV and PELV terminals.
Verification of the basic insulation between the H LV m ains circuits and the ELV circuit on the
one hand, and verification of the supplem entary insulation between the ELV circuit and the
PELV/SELV circuits on the other hand is not possible using a black box test m ethod as it is
not possible to ensure that the correct test voltage will be applied to each insulation layer.
Design verification in single fault condition is not possible either with the black box test
method. The double insulation consists of a layer of basic insulation and a layer of
supplementary insulation (in this exam ple equivalent to basic insulation). I n single fault
conditions each of these layers should be subjected to fault (shorted), one at a time, and it
should be verified that the remaining, intact insulation layer still provides at least basic /
supplementary protection.
I EC 62052-31 :201 5 © I EC 201 5
– 1 49 –
Annex C
(informative)
Examples for direct connected meters equipped with
supply control and load control switches
Figure C. 1 shows a single phase two wire meter with an UC2 suppl y control switch (SCS) and
a 25A load control switch (LCS).
For m arking of switches, see 5. 3. 5.
The SCS m ay be controlled by a paym ent m etering function, a lim iter function and/or
rem otel y. The m eter and the SCS are protected by the upstream – suppl y side – protection.
The LCS controls part of the load, and m ay be controlled by a time switch function and/or
rem otely. I t is protected by the downstream – load side – protection.
The protection network P is a component or network of com ponents on the suppl y side of the
meter power suppl y, suppl y voltage input and/or PLC coupling circuit, for the purpose of
protecting such circuits from severe differential mode surges. Typical devices are voltage
operated surge arrestors with unspecified operating voltage and surge capacity.
The coupling network C is a component or network of components connected in parall el with
the terminals of a supply control switch, for the purpose of providing functionality when the
switch is in the open position. Typical functionality is load side voltage sensing and PLC
signal coupling. I n its sim plest form, the coupling network C is the dielectric of the load switch
housing which must withstand severe com mon and differential mode surges.
IEC
Key
C
M
P
coupli ng n etwork
m easuring elem ent
protection network
Figure C.1 – Single phase two wire meter with UC2 SCS and 25A LCS
Figure C. 2 shows a three phase four wire meter with an U C2 suppl y control switch (SCS),
also switching the neutral, and a 2A auxiliary control switch (ACS) with independent term inals.
The SCS m ay be controlled by a paym ent m etering function, a limiter function and/or
remotel y. The m eter and the SCS are protected by the upstream – suppl y side – protection.
– 1 50 –
I EC 62052-31 :201 5 © I EC 201 5
The ACS controls part of the load, eventuall y through a contactor – and may be controlled by
a time switch function and/or remotel y. The contactor and the downstream protection of the
ACS are not shown.
IEC
Key
C
M
P
coupli ng n etwork
m easuring elem ent
protection n etwork
Figure C.2 – Three phase four wire meter with UC2 SCS
and 2A auxiliary control switch
I EC 62052-31 :201 5 © I EC 201 5
– 1 51 –
Annex D
(normative)
Test circuit diagram for the test of long term overvoltage withstand
Figure D. 1 shows the test circuit diagram, for the long term overvoltage withstand test
specified in 6. 1 0. 3.2 in the case of testing a three-phase four wire m eter.
Figure D. 2 shows the voltages that appear at the terminals of the EUT during the test.
IEC
Key
C
M
P
coupli ng n etwork
m easuring elem ent
protection network
Figure D.1 – Circuit for three-phase four-wire meters to simulate
long term overvoltage, voltage moved to L3
L1
L3
L1
L2
L3 = 0
L2
IEC
Figure D.2 – Voltages at the meter under test
– 1 52 –
I EC 62052-31 :201 5 © I EC 201 5
Annex E
(normative)
Test circuit diagram for short current test on
the current circuit of direct connected meters
Figure E. 1 shows the principal test circuit diagram for short current tests on the current circuit
of direct connected meters equipped or not with a suppl y control switch, specified in 6.1 0. 5,
6. 1 0. 6. 6 6. 1 0. 6.7 and 6. 1 0. 6. 8.
NOTE 1 Fig ure E. 1 is based on Fig ure 9 of I EC 60947-1 : 2007.
For the verification of the ability to carry the rated safe short-time withstand current – see
6. 1 0. 6. 6 – and for the verification of the ability to carry the rated operational short-time
withstand current – see 6.1 0. 6. 7 – the switch under test shall be closed.
For the verification of the ability to make the rated short-circuit current – see 6. 1 0.6. 8 – the
switch under test is open before the test and it closes during the test.
Key
S Supply
E Earthing point
U Unit under test (SCS)
R Adjustable resistor
X Adjustable reactor
T Test switch
V Voltage sensors
I Current sensor
B Temporary connection
for calibration
F Fusible element
L Limiting resistor
R
X
M Measuring element
P Protection network
C Coupling network
U
P
M
C
I
T
B
S
V1
V2
L
V3
D*
F
E
Diode D* is optional. It is used to improve the timing accuracy of the test switch T turn off.
IEC
Figure E.1 – Test circuit for verification of short-time withstand current
test on current circuits with and without supply control switches
Figure E. 2 shows the voltage and current waveforms during calibration and test operation.
NOTE 2 Fig ure E. 2 is based on Fig ure 1 3 of I EC 60947-1 : 2007.
I EC 62052-31 :201 5 © I EC 201 5
– 1 53 –
A1
Current
A2
a)
=
Calibration of
circuit
A1
=
Prospecti ve peak
m aking current
A2
2 2
=
Prospecti ve
symm etrical
carryin g current
(r. m . s. value)
=
Applied voltage
(r. m . s. value)
=
Test operation
=
Suppl y voltage,
(r. m . s. value)
B1
2 2
Voltage
B1
Test switch opened on supply voltage zero,
supply voltage removed
b)
Test current
Test voltage
B2
2 2
Test switch
closed on supply
voltage zero
B2
Supply
voltage
IEC
NOTE 1 Th e am plitude of th e voltage trace, after i nitiati on of th e test cu rrent, vari es accordi ng to th e rel ative
positions of the closi ng device, the ad justable im ped ances, the voltage sensors and according to the test circuit
diag ram .
NOTE 2 Th e supply vol tage i s rem oved wh en the test switch is opened, which sim ulates the operati on of a suppl y
side protection device after on e half cycl e.
Figu re E.2 – Example of short-circu it carrying test record
in the case of a single-pole equipment on single-phase a.c.
– 1 54 –
I EC 62052-31 :201 5 © I EC 201 5
Annex F
(informative)
Examples for voltage tests
Figure F. 1 shows the test arrangement for voltage tests in the case of a 3 phase 4 wire direct
connected m eter with supply control and load control switches.
IEC
Figure F.1 – Test arrangement for voltage tests: 3 phase 4 wire direct
connected meter with supply control and load control switches
I EC 62052-31 :201 5 © I EC 201 5
– 1 55 –
The tests are the following:
1 ) Testing of voltage circuits with im pulse voltage / surge, see 6. 1 0. 3. 3 and 6. 1 0. 3. 4:
•
1 a – on phase L1 (suppl y control switch closed);
•
1 b – on phase L2 (supply control switch closed);
•
1 c – on phase L3 (supply control switch closed);
•
1 d, 1 e – on auxiliary suppl y.
2) I m pulse voltage test:
•
2a – between all H LV term inals and earth, see 6. 1 0. 4. 3.3 a);
•
2b – between the term inals of all voltage and current circuits and all other H LV
term inals, see 6. 1 0. 4. 3. 3 b);
•
2c – between HLV I /O terminals and all other H LV term inals, see 6. 1 0. 4. 3. 3 b);
•
2d – between H LV auxiliary suppl y terminals and all other H LV term inals, see
6. 1 0. 4. 3. 3 b);
3) AC voltage test:
•
3a – between all H LV term inals and earth, see 6. 1 0. 4. 3.4, Table 25 a);
•
3b – between the term inals of all voltage and current circu its and all other H LV
term inals, see 6. 1 0. 4. 3. 4, Table 25 b);
•
3c – between H LV I /O terminals and all other HLV terminals, see 6.1 0.4. 3. 4, Table 25
b);
•
3d – between H LV auxiliary suppl y term inals and all other H LV term inals, see
6. 1 0. 4. 3. 4, Table 25 b);
4) Surge voltage test across open contacts of supply control switches, see 6. 1 0. 6. 5.
Figure F.2 shows the test arrangem ent for voltage tests in the case of a 3 phase 4 wire
transformer connected meter.
– 1 56 –
I EC 62052-31 :201 5 © I EC 201 5
IEC
Fi g u re F . 2 – Test arran g em en t for vol tag e tests:
3 ph ase 4 wi re tran sform er con n ected m eter
I EC 62052-31 :201 5 © I EC 201 5
– 1 57 –
The tests are the following:
1 ) Testing of voltage circuits with im pulse voltage / surge, see 6. 1 0. 3. 3 and 6. 1 0. 3. 4:
•
1 a – on phase L1 voltage measurement circuit;
•
1 b – on phase L2 voltage m easurement circuit;
•
1 c – on phase L3 voltage m easurem ent circuit;
•
1 d, 1 e – on auxiliary suppl y.
2) I m pulse voltage test:
•
2a – between all H LV terminals and earth, see 6. 1 0. 4. 3. 3 a);
•
2b – between the terminals of all voltage circuits and all other HLV terminals, see
6. 1 0. 4. 3. 3 b);
•
2c – between the term inals of phase L1 current circuits and all oth er H LV terminals,
see 6. 1 0. 4. 3. 3 b);
•
2d – between the term inals of phase L2 current circuits and all other HLV term inals,
see 6. 1 0. 4. 3. 3 b);
•
2e – between the term inals of phase L3 current circuits and all other HLV term inals,
see 6. 1 0. 4. 3. 3 b);
•
2f – between H LV I /O terminals and all other H LV terminals, see 6. 1 0. 4. 3. 3 b);
•
2g – between H LV auxiliary suppl y term inals and all other H LV terminals, see
6. 1 0. 4. 3. 3 b);
3) AC voltage test, see 6. 1 0. 4.3. 4:
•
3a – between all H LV terminals and earth, see 6. 1 0. 4. 3.4, Table 25 a);
•
3b – between the terminals of all voltage circuits and all other HLV terminals, see
6. 1 0. 4. 3. 4, Table 25 b);
•
3c – between the term inals of phase L1 current circu its and all other H LV term inals see
6. 1 0. 4. 3. 4, Table 25 b);
•
3d – between the terminals of phase L2 current circuits and all other HLV term inals,
see 6. 1 0. 4. 3. 4, Table 25 b);
•
3e – between the terminals of phase L3 current circuits and all other HLV term inals,
see 6. 1 0. 4. 3. 4, Table 25 b);
•
3f – between HLV I /O term inals and all other H LV term inals, see 6. 1 0. 4.3.4, Table 25
b);
•
3g – between H LV auxiliary suppl y term inals and all other H LV term inals, see
6. 1 0. 4. 3. 4, Table 25 b).
– 1 58 –
I EC 62052-31 :201 5 © I EC 201 5
An n e x G
(normative)
Ad d i ti o n a l a . c .
vo l ta g e te s ts fo r e l e c tro m e c h a n i c a l m e te rs
The purpose of this test is to verify that the fram e holding the driving elem ents is suitabl y
insulated from the H LV circuits and – in the case of meters of protective class I I – from the
accessible surfaces.
The test shall be carried out in accordance with Table G. 1 . Where these levels exceed the
levels in Table 25, the levels in Table G. 1 shall appl y.
Tabl e G . 1
– AC v o l t a g e t e s t s o f e l e c t ro m e c h a n i c a l
AC
P o i n ts o f a p p l i c a ti o n
A)
m e t e rs
t e s t v o l t a g e V r. m . s .
o f th e t e s t vo l ta g e
P ro t e c t i v e c l a s s I
P ro t e c t i v e c l a s s I I
2 000
2 000
500
500
Te sts to be ca rrie d o ut with th e co ve r a n d te rm in a l co ve r
re mo ve d, b e twe e n , o n th e o n e h a n d, th e
fram e
a n d, o n th e
o th e r h a n d:
a) each current circuit which, in n orm al service, is separated
and suitabl y insul ated from the other ci rcuits 1 ;
b) each voltage circu it, or set of voltag e circuits havi ng a
comm on point wh ich, in n orm al service, is separated and
suitabl y insul ated from the oth er circuits 1 ;
c) each H LV au xili ary circuit or a set of au xiliary ci rcuits
having a comm on point;
d) each assem bly of cu rrent-voltage wi ndi ngs of one and the
sam e drivi ng el em ent which, i n norm al service, are
connected together but separated and suitably i nsul ated
from the other circuits 2 ;
e) each au xi liary ci rcuit with a vol tage l evel eq ual or below
the valu e specified in 6. 3. 2.
B)
Te s ts wh ich ma y b e ca rrie d o ut with th e te rm in a l co ve r
re m o ve d, b ut with th e co ve r in p la ce wh e n it is m a de o f m e ta l:
a) between the current circuit and the voltag e circuit of each
dri vin g el em ent, norm ally conn ected tog ether, this
connection being tem poraril y broken for th e pu rpose of the
test 3 .
C)
600
4
2
3
4
4
A dditio n a l te st fo r in s ula tin g e n clo se d m e te rs o f p ro te ctive
–
2 000
a) between the fra m e and earth;
b) between, on the on e hand, all conducti ve parts insid e the
m eter case connected tog ether and, on the other hand, al l
–
40
conducti ve parts, outsid e the m eter case that are
accessible with th e test fing er, connected tog ether.
The sim pl e breaking of the connection, which is norm ally incl uded between current and vol tage wi ndi ngs, is
not generall y sufficient to ensu re suitable i nsulati on, which can withstand a test voltage of 2 000 V.
Tests in part A) I tem s a) and b) g en erall y appl y to m eters operated from instrum ent transform ers and also to
certain special m eters havi ng separate cu rrent and voltage wi ndings.
Circuits, which have been subj ected to tests in part A) I tem s a) and b) are not subjected to the test i n I tem
d). When the voltag e circuits of a pol yphase m eter have a comm on point i n n orm al servi ce, this comm on
point sh all be m aintain ed for the test an d, in this case, al l th e circuits of the dri vin g el em ents are su bjected
to a singl e test.
I t is not, strictly speaking, a di electric strength test, but a m eans of verifyin g that the i nsulation distances are
sufficient wh en th e conn ecting device is open.
or twice th e voltag e applied to the voltag e win din gs und er reference cond itions, when th is voltage is g reater
than 300 V (the hi gh er val ue).
cla ss II
1
600
Durin g th is te st n o fla sh o ve r, disrup tive disch a rge o r p un cture sh a ll occur.
I EC 62052-31 :201 5 © I EC 201 5
– 1 59 –
An nex H
(normative)
Test equipmen t for cable flexi on and pull test
Figure H . 1 shows the test equipm ent for the cable flexion and pull test. The distance of the
platen from the clamping unit, the diam eter of the bushing, the m ass to be applied during the
flexion test and the pull force to be applied after the flexion test is shown in Table H . 1 .
Dimensions in millimetres
H
Terminal
under test
37,5
Platen
Bushing
hole
Mass
IEC
Fi gu re H . 1 – Test eq u i pmen t for cable fl exion an d pu ll test (see 6.9. 7. 3)
– 1 60 –
I EC 62052-31 :201 5 © I EC 201 5
Table H.1 – Test values for flexion and pull-out tests for round copper conductors
Conductor cross-section
Diameter of bu shing hole
a, b
Height H a
Mass
Pulling force
mm 2
mm
mm
kg
N
1 ,0
6, 5
260
0, 4
35
1 ,5
6, 5
260
0, 4
40
2, 5
9, 5
280
0, 7
50
4, 0
9, 5
280
0, 9
60
6, 0
9, 5
280
1 ,4
80
1 0, 0
9, 4
280
2, 0
90
1 6, 0
1 3, 0
300
2, 9
1 00
25, 0
1 3, 0
300
4, 5
1 35
35, 0
1 4, 5
320
6, 8
1 90
50, 0
1 5, 9
343
9, 5
236
a
Tolerances: for hei ght H ± 1 5 mm , for diam eter of th e bushin g hol e ± 2 mm .
b
I f the bushin g hol e diam eter is not l arg e en ou gh to accomm odate the conductor with out bi n ding, a bushin g
having the n ext l arger hol e size m ay be used.
NOTE The val ues have been taken from I EC 60947-1 : 2007, Table 5.
I EC 62052-31 :201 5 © I EC 201 5
– 1 61 –
An n e x I
(informative)
Ro u ti n e te s ts
I.1
G e n e ra l
NOTE This Annex is based on I EC 61 01 0-1 : 201 0, Ann ex F.
The manufacturer should perform the tests of I . 2 to I . 4 on equipment produced, which has
both hazardous live parts and accessible conductive parts.
As specified in I EC 62058-1 1 : 2008, 1 00 % inspection may be performed or lot-by-lot
inspection by attributes, with acceptance number 0.
Unless it can be clearl y shown that the result of the tests cannot be invalidated by subsequent
m anufacturing stages, tests should be made with equipm ent full y assembled. Com ponents
should not be unwired, modified or disassem bled for the test. The equipment does not need to
be energized during the tests.
Wrapping the equipment in foil is not required. H umidity preconditioning is not required.
Test site altitude correction of the test voltage is not required.
The voltage test equipment should be able to maintain the required voltage for the specified
period of tim e. N o other requirem ents appl y.
Co n form ity is ch e cke d b y in s p e ctio n .
I.2
P ro t e c t i v e e a rt h
A con tin uity te st is m a de b e twe e n th e p ro te ctive con ductor te rm in a l o n th e on e s ide ,
a cce ssib le
co n ductive
p a rts
wh ich
a re
re quire d b y 6. 5. 2
to
be
con n e cte d to
th e
a n d a ll
p rote ctive
con ductor te rm in a l on th e oth e r s ide .
NOTE No val ue is specified for the test current.
I.3
AC p o w e r-fre q u e n c y h i g h - vo l t a g e t e s t fo r m a i n s - c i rc u i t s
The test method specified in 6. 1 0. 2. 5 shall be used:
•
•
•
I.4
the test voltage shall be selected from Table 1 0 for basic insulation;
the test duration shall be reduced to 2 s;
the rise time and the fall tim e of the test voltage shall be > 2 s.
M a i n s - c i rc u i t s w i t h v o l t a g e l i m i t i n g d e vi c e s
For m ains-circuits with voltage lim iting devices the test specified can be carried out using a
test voltage of 0, 9 tim es the working voltage of the voltage lim iting device but not less than
twice the working voltage of the mains-circuit.
– 1 62 –
I EC 62052-31 :201 5 © I EC 201 5
Annex J
(informative)
Examples of battery protection
NOTE This Annex is based on I EC 60255-27: 201 3, An nex F.
This annex gives typical examples of battery protection to reduce overheating or explosion
risk under a single-fault condition (see Figures J. 1 and J. 2).
Reverse-current protection devices
+5 V from power supply
Non-rechargeable battery
Battery-powered RAM module
IEC
Figure J.1 – Non-rechargeable battery protection
+5 V power supply
Rechargeable battery. Charge
and discharge currents shall
be limited to safe value
Battery-powered
RAM module
Limiting
fuse
IEC
Figure J.2 – Rechargeable battery protection
I EC 62052-31 :201 5 © I EC 201 5
– 1 63 –
An n e x K
(informative)
Ra ti o n a l e fo r s p e c i fyi n g o ve rvo l ta g e c a te g o ry I I I
K. 1
Tra n s i e n t o ve rv o l t a g e re q u i re m e n t s i n TC 1 3 s t a n d a rd s
Standards established by I EC TC 1 3 related to m etering equipm ent have evolved over tim e
and although their prim e focus is on m easurement accuracy, they have adopted and
augm ented requirem ents, test meth ods and test conditions related to safety through their
various editions.
I EC 62052-31 is the latest stage in this process and it aligns the safety requirem ents, test
methods and test conditions of electrical energy meters with that of other electrical an d
electronic products used in dom estic, commercial and industrial environments.
The standards published by I EC TC 1 3 so far did not m ention overvoltage categories; this
evolution is introduced wi th I EC 62052-31 .
The specified values of clearances, creepage distances and impulse withstand voltages used
in the previousl y published standards correspond to overvoltage category I I I , and have been
used to design and test electrical energ y meters for the past 20 years. The specified values
have been proven through practical experience and extensive use in the field.
Electricity meters are som etimes used in environm ents norm all y classified as overvoltage
category I V, e.g. substations and transform er stations, but onl y with appropriate additional
protection such as fuses or external overvoltage protection elem ents. Also for these
applications of electricity m eters, the design requirem ents for clearances, creepage distances
and im pulse test voltages given in this standard, according to the overvoltage category I I I , are
considered to be appropriate by TC 1 3. See also 1 .4.1 .
Subclause 1 . 4. 2 allows the supplier and the m anufacturer to agree on specifying impulse
withstand voltages higher than what is required for overvoltage category I I I , or even
overvoltage category I V where it would be appropriate, but recognises that in the m ajority of
applications, overvoltage category I I I is sufficient.
K. 2
E l e c t ri c i t y m e t e rs m e n t i o n e d i n b a s i c s a fe t y p u b l i c a t i o n s a n d g ro u p s a fe t y
pu b l i cati o n s
K. 2 . 1
I E C 6 0 6 6 4-1
Electricity m eters are common and recognisable devices and as such they are m entioned in
the horizontal safety standard I EC 60664-1 : 2007, Insulation coordination for equipment within
low-voltage systems – Part 1: Principles, requirements and tests.
The following subclause of I EC 60664-1 : 2007 defines the use of overvoltage categories I I I
and I V as follows:
Subclause 4. 3. 3. 2. 2: Equipment energized directly from the supply mains specifies this:
Technical committees shall specify the overvoltage category as based on the following
general explanation of overvoltage categories (see also 443 of I EC 60364-4-44: 2007):
– Equipment of overvoltage category I V is for use at the origin of the installation.
NOTE 1 Exam ples of such equi pm ent are electricity m eters and prim ary overcu rrent protection
equi pm ent.
– 1 64 –
I EC 62052-31 :201 5 © I EC 201 5
– Equipm ent of overvoltage category I I I is equipm ent in fixed installations and for cases
where the reliability and the availability of the equipment are subj ect to special
requirem ents.
NOTE 2 Exam ples of such equipm ent are switches in the fi xed installati on and equi pm ent for industrial
use with perm an ent con nection to the fi xed installation.
A note is onl y a general inform ation. Electricity meters are mentioned as an example;
I EC 60664-1 , being ahorizontal safety standard, neither asks for applying category I V to
electricity meters nor gives an y special requirem ents covering electricity m eters.
K. 2 . 2
I E C 6 0 3 6 4- 4-4 4
IEC 60664-1 : 2007, 4. 3. 3. 2. 2 also refers to 443 of I EC 60364-4-44:2007,
L o w-vo lta ge e le ctrica l
in sta lla tio n s – Pa rt 4-4 4: Pro te ction for s a fe ty – Pro te ctio n a ga in st vo lta ge disturb a n ce s a n d
e le ctro m a gn e tic dis turb a n ce s .
Subclause 443.2. 2:
Re la tion s h ip
ove rvo lta ge ca te go rie s
states this:
b e twe e n
im p uls e
with s ta n d
vo lta ge s
of
e quip m e n t
and
Equipm ent with an im pulse withstand voltage corresponding to overvoltage category I V
is suitable for use at, or in the proximity of, the origin of the installation, for example
upstream of the main distribution board. Equipm ent of category I V has a very high
im pulse withstand capability providing the required high degree of reliability.
NOTE Exam ples of such eq uipm ent are electricity m eters, prim ary overcurrent protecti on d evices an d
ripple control units.
Equipm ent with an impulse withstand voltage corresponding to overvoltage category I I I
is for use in the fixed installation downstream of, and including the main distribution
board, providing a high degree of availability.
Again, electricity meters are m entioned in the N ote as an
I V.
e xa m p le
under overvoltage category
As electricity m eters are typicall y installed on distributions boards, overvoltage category I I I is
therefore considered to be appropriate.
The definitions above both relate to fixed installations, and since an electricity meter form s
part of a fixed installation, both categories may be applicable.
K. 2 . 3
I E C 6 1 0 1 0-1
I EC 61 01 0-1 : 201 0,
and
la b ora tory
use
Sa fe ty
–
re q uire m e n ts
Pa rt
1:
G e n e ra l
meters as an example: “may include”.
fo r e le ctrica l
re quire m e n ts.
e q uip m e n t
fo r m e a sure m e n t,
co n tro l,
Annex K. 1 also mentions electricity
OVERVOLTAGE CATEGORY lll is for equipm ent intended to form part of a building
wiring installation. Such equipment includes socket outlets, fuse panels, and som e
MAI N S installation control equipment. Manufacturers m ay also design equipm ent for
OVERVOLTAGE CATEGORY I V when a higher degree of reliability and avail ability is
desired.
OVERVOLTAGE CATEGORY lV is for equipment installed at or near the origin of the
electrical suppl y to a building, between the building entrance and the main distribution
board. Such equipm ent m ay include electricity tariff meters and primary overcurrent
protection devices.
The description of the OVC I V m entions electricity meters as an exam ple, but this cannot be
interpreted as a requirement.
I EC 62052-31 :201 5 © I EC 201 5
K.3
– 1 65 –
Conclusion
From the above it is clear that the choice of TC 1 3 to use clearances, creepage distances and
im pulse withstand voltages corresponding to Overvoltage Category I I I , while allowing the use
of higher impulse withstand voltages as agreed by the m anufacturer and the purchaser, is
technicall y and procedurall y correct.
– 1 66 –
I EC 62052-31 :201 5 © I EC 201 5
An n e x L
(informative)
O ve rvi e w o f s a fe t y a s p e c ts c o ve re d
The following Table L. 1 provides an overview of the safety aspects covered in this standard .
The first two columns contain the Contents of this docum ent.
The third column references clauses/subclauses in horizontal / group / other product safety
standards on which the given clause is based:
I EC
I EC
I EC
I EC
I EC
I EC
I EC
I EC
•
•
•
•
•
•
•
•
60255-27:201 3;
60364-1 : 2005;
60664-1 : 2007;
60947-1 : 2007;
61 000-4-5: 201 4;
61 01 0-1 : 201 0;
61 1 80-1 : 1 992;
62477-1 : 201 2.
The fourth colum n references safety clauses/subclauses of current TC 1 3 type test standards,
which are replaced by this standard.
Tabl e L. 1
Cl au s e
– O v e rv i e w o f s a fe t y a s p e c t s
Ti tl e
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
I ntrod uction
1
Scope and object
I EC Guide 1 04
I SO / I EC
Guid e 51
–
–
–
–
–
1 .1
Scope
–
1 .2
Object
I EC 61 01 0-1 : 201 0,
1 .2
1 . 2. 1
Aspects included i n scope
I EC 61 01 0-1 : 201 0,
1 . 2. 1
1 . 2. 2
Aspects excl uded from scope
I EC 61 01 0-1 : 201 0,
1 . 2. 1
1 .3
Verification
I EC 61 01 0-1 : 201 0,
1 .3
1 .4
Envi ronm ental conditi ons
I EC 61 01 0-1 : 201 0,
1 .4
1 . 4. 1
Norm al envi ronm ental
conditions
1 . 4. 2
Exten ded en vironm ental
conditions
I EC 62052-1 1 : 2003,
Clause 1
I EC 62052-21 : 2004,
Clause 1
–
Modified
I EC 62052-1 1 : 2003,
6. 1 , 6. 2
I EC 62052-21 : 2004,
6. 1 , 6. 2
Modified
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 67 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
1 . 4. 3
2
Extrem e en vi ronm ental
conditions
Norm ative references
3
Term s and defi nitions
3. 1
Equipm ent an d states of
equi pm ent
I EC 60721 -30: 1 984,
5. 2
I EC 61 01 0-1 : 201 0,
Clause 2
I EC 60050
–
I EC 62052-1 1 : 2003,
Clause 2
I EC 62052-21 : 2004,
Clause 2
I EC 62052-1 1 : 2003
Clause 3
I EC 62052-21 : 2004,
Clause 3
I EC 61 01 0-1 : 201 0,
3. 1
Modified
Modified
I EC 62052-1 1 : 2003
Clause 3
3. 2
Parts and accessories
I EC 61 01 0-1 : 201 0,
3. 2
I EC 62052-21 : 2004,
Clause 3
Modified
I EC 62055-31 : 2005,
Clause 3
3. 3
Quantiti es
I EC 61 01 0-1 : 201 0,
3. 3
Modified
3. 4
Tests
I EC 61 01 0-1 : 201 0,
3. 4
Modified
3. 5
Safety term s
I EC 61 01 0-1 : 201 0,
3. 5
I EC 62052-1 1 : 2003,
3. 3
I EC 61 01 0-1 : 201 0,
3. 6
I EC 62052-1 1 : 2003,
3. 4
IEC 60255-27: 201 3,
3
I EC 62052-21 : 2004,
3. 4
3. 6
I nsulation
3. 7
Term s related to switches of
m etering equi pm ent
4
Tests
I EC 61 01 0-1 : 201 0,
Clause 4
4. 1
General
I EC 61 01 0-1 : 201 0,
4. 1
Type test – sequ ence of tests
I EC 61 01 0-1 : 201 0,
4. 2
Reference test conditi ons
I EC 61 01 0-1 : 201 0,
4. 2
4. 2
4. 3
I EC 60050441 : 1 984
I EC 60947-1 : 2007
4. 3. 1
Atm ospheric conditi ons
I EC 60068-1 : 201 3
4. 3. 2
State of the equi pm ent
I EC 61 01 0-1 : 201 0,
4. 3. 2
Modified
Modified
I EC 62052-21 : 2004,
3. 5
Modified
I EC 62052-1 1 : 2003,
Annex F
I EC 62052-21 : 2004,
Annex E
I EC 62052-1 1 : 2003,
Clause 6
I EC 62052-21 : 2004,
Clause 6
Modified
Modified
I EC 62052-1 1 : 2003
7. 3. 1
I EC 62052-21 : 2004,
7. 3. 2. 1
Modified
– 1 68 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
Modified to
cover
m odification /
openin g of the
DUT
4. 3. 2. 1
General
I EC 61 01 0-1 : 201 0,
4. 3. 2. 1
4. 3. 2. 2
Position of equi pm ent
I EC 61 01 0-1 : 201 0,
4. 3. 2. 2
Modified to
includ e m atching
socket
4. 3. 2. 3
Plug-i n m odules
I EC 61 01 0-1 : 201 0,
4. 3. 2. 3
Com m unication
m odules etc.
4. 3. 2. 4
Covers and rem ovable parts
I EC 61 01 0-1 : 201 0,
4. 3. 2. 4
4. 3. 2. 5
Con nection of the voltage an d
current circuits
I EC 61 01 0-1 : 201 0,
4. 3. 2. 5
Modified for
m etering
4. 3. 2. 6
Suppl y and load control
switch es
–
Specific for
m etering
4. 3. 2. 7
Con nection of the auxiliary
circuits
–
Specific for
m etering
4. 3. 2. 8
Con nection of batteri es
–
4. 3. 2. 9
Protective con ductor term inals
4. 3. 2. 1 0
Physical token carriers
4. 3. 2. 1 1
Test cables
4. 3. 2. 1 2
I nform ation on tests
I EC 61 01 0-1 : 201 0,
4. 3. 2. 7
Specific for
m etering
–
I EC 60947-1 : 2007,
8. 3. 3. 3. 4
I EC 6025527: 201 3, 1 0. 4
–
–
4. 4
Testing in single fault con dition
I EC 61 01 0-1 : 201 0,
4. 4
4. 4. 1
General
I EC 61 01 0-1 : 201 0,
4. 4. 1
–
4. 4. 2
Application of fau lt conditi ons
I EC 61 01 0-1 : 201 0,
4. 4. 2
–
4. 4. 2. 1
General
I EC 61 01 0-1 : 201 0,
4. 4. 2. 1
–
4. 4. 2. 2
Protective im pedance
I EC 61 01 0-1 : 201 0,
4. 4. 2. 2
–
4. 4. 2. 3
Equipm ent or parts for shortterm or interm ittent operati on
I EC 61 01 0-1 : 201 0,
4. 4. 2. 4
–
4. 4. 2. 4
Transform ers
I EC 61 01 0-1 : 201 0,
4. 4. 2. 7
–
4. 4. 2. 4. 1
General
I EC 61 01 0-1 : 201 0,
4. 4. 2. 7. 1
–
4. 4. 2. 4. 2
Short circuit test for voltag e
transform ers
I EC 61 01 0-1 : 201 0,
4. 4. 2. 7. 2
–
4. 4. 2. 4. 3
Overload
I EC 61 01 0-1 : 201 0,
4. 4. 2. 7. 3
–
4. 4. 2. 4. 4
Open ci rcuit of current
transform ers
–
–
–
Modified for
m etering. Parts
not relevant for
m etering
om itted.
Specific for
m etering
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 69 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
4. 4. 2. 5
Equipm ent with au xili ary
suppl y
I EC 61 01 0-1 : 201 0,
4. 4. 2. 9
–
4. 4. 2. 6
Mai ns-circuits and hazardous
voltage non -m ains-circu its
IEC 60255-27: 201 3,
5. 2. 2. 6
–
4. 4. 2. 7
Overloads
IEC 60255-27: 201 3,
5. 2. 2. 7
–
4. 4. 2. 8
I nterm ittently rated resistors
IEC 60255-27: 201 3,
5. 2. 2. 8
–
4. 4. 2. 9
Dou ble i nsulati on
4. 4. 3
Duration of tests
I EC 61 01 0-1 : 201 0,
4. 4. 3. 1 .
–
4. 4. 4
Conform ity after application of
fault cond itions
I EC 61 01 0-1 : 201 0,
4. 4. 4
–
4. 4. 4. 1
General
I EC 61 01 0-1 : 201 0,
4. 4. 4. 1
–
4. 4. 4. 2
Tem peratu re
I EC 61 01 0-1 : 201 0,
4. 4. 4. 2
–
4. 4. 4. 3
Spread of fi re
I EC 61 01 0-1 : 201 0,
4. 4. 4. 3
–
4. 4. 4. 4
Other hazards
I EC 61 01 0-1 : 201 0,
4. 4. 4. 4
–
5
5. 1
0
I nform ation and m arkin g
req uirem ents
General
I EC 61 01 0-1 : 201 0,
Clause 5
I EC 62477-1 : 201 2,
Clause 6
I EC 62052-1 1 : 2003,
5. 1 2
I EC 62052-21 : 2004,
5. 1 2
I EC 62055-31 : 2005,
5. 1 3
Marked item s
specific for
m etering
I EC 62477-1 : 201 2,
6. 1
Labels, signs an d signals
5. 2. 1
General
I EC 62477-1 : 201 2,
6. 4. 3. 1
5. 2. 2
Durabi lity of m arkin gs
I EC 61 01 0-1 : 201 0,
5. 3
Modified
5. 3
I nform ation for selection
I EC 62477-1 : 201 2,
6. 2
Modified for
m etering
5. 3. 1
General
5. 3. 2
General inform ation
5. 3. 3
I nform ation rel ated to m eters /
m etering el em ents
5. 3. 4
I nform ation rel ated to stand alon e tariff-and load control
equi pm ent
5. 3. 5
I nform ation rel ated to su ppl y
control an d load control
switch es
5. 4
I nform ation for install ation an d
comm issioning
I EC 62052-21 : 2004,
5. 1 2
I EC 62055-31 : 2005,
Annex C
I EC 62477-1 : 201 2,
6. 3
Modified for
m etering
– 1 70 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
5. 4. 1
General
5. 4. 2
Handlin g and m ountin g
I EC 62477-1 : 201 2,
6. 3. 4
5. 4. 3
Enclosure
I EC 62477-1 : 201 2,
6. 3. 5
Modified for
m etering
5. 4. 4
Connection
I EC 62477-1 : 201 2,
6. 3. 6
Modified for
m etering
5. 4. 4. 1
General
I EC 62477-1 : 201 2,
6. 3. 6. 1
Modified for
m etering
5. 4. 4. 2
Con nection diagram s
I EC 62477-1 : 201 2,
6. 3. 6. 2
Modified for
m etering
5. 4. 4. 3
Mai ns term inals
5. 4. 4. 4
Au xili ary term inals
5. 4. 4. 5
Con nectin g cabl es
I EC 62477-1 : 201 2,
6. 3. 6. 3
Modified for
m etering
5. 4. 4. 6
I solation from the suppl y
I EC 62477-1 : 201 2,
6. 5. 5
Modified for
m etering
5. 4. 5
Protection
I EC 62477-1 : 201 2,
6. 3. 7
Modified for
m etering
5. 4. 5. 1
Protective class and earthin g
–
5. 4. 5. 2
External protection d evices
–
5. 4. 6
Au xili ary power suppl y
–
5. 4. 7
Suppl y for external d evices
–
5. 4. 8
Batteries
5. 4. 9
Self-consum ption
5. 4. 1 0
Com m issioning
5. 5
I nform ation for use
5. 5. 1
General
5. 5. 2
Display, push buttons an d
other controls
5. 5. 3
Switch es
5. 5. 4
Connection to user’s
equi pm ent
5. 5. 5
External protection d evices
5. 5. 6
Cleanin g
5. 6
I nform ation for m ainten ance
6
Protection ag ainst el ectrical
shock
Specific for
m etering
Specific for
m etering
IEC 60255-27: 201 3,
9. 1 . 8. 1 .
–
I EC 61 01 0-1 : 201 0,
5. 4. 6
IEC 60364-1 :2005,
1 31 . 7
Modified for
m etering
I EC 62477-1 : 201 2,
6. 4
Modified for
m etering
I EC 62477-1 : 201 2,
6. 5. 1
Modified for
m etering
I EC 61 01 0-1 : 201 0,
6. 1 . 1
IEC 60255-27: 201 3,
5. 1
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 71 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
6. 1
General requi rem ents
6. 2
Determ ination of accessible
parts
I EC 61 01 0-1 : 201 0,
6. 1 . 1
I EC 62052-1 1 : 2003,
5. 1
IEC 60255-27: 201 3,
5. 1
I EC 62052-21 : 2004,
5. 1
I EC 61 01 0-1 : 201 0,
6. 2
I EC 61 01 0-1 : 201 0,
6. 2. 1
6. 2. 1
General
6. 2. 2
Exam ination
I EC 61 01 0-1 : 201 0,
6. 2. 2
6. 2. 3
Open ings above parts th at are
hazardous live
I EC 61 01 0-1 : 201 0,
6. 2. 3
6. 2. 4
Open ings for pre-set controls
I EC 61 01 0-1 : 201 0,
6. 2. 4
6. 2. 5
Wiring term inals
IEC 60255-27: 201 3,
5. 1 . 5. 2. 6
6. 3
Lim it values for accessible
parts
I EC 61 01 0-1 : 201 0,
6. 3
6. 3. 1
General
6. 3. 2
Levels in n orm al con dition
I EC 61 01 0-1 : 201 0,
6. 3. 1
6. 3. 3
Levels in sin gle fault conditi on
I EC 61 01 0-1 : 201 0,
6. 3. 2, .
6. 4
Prim ary m eans of protection
(protection ag ainst di rect
contact)
6. 4. 1
General
I EC 61 01 0-1 : 201 0,
6. 4. 1
6. 4. 2
Equipm ent case
I EC 61 01 0-1 : 201 0,
6. 4. 2
6. 4. 3
Basic insulation
I EC 61 01 0-1 : 201 0,
6. 4. 3
6. 4. 4
I m pedance
I EC 61 01 0-1 : 201 0,
6. 4. 4
6. 5
Additional m eans of protection
in case of singl e fault
conditions (protection agai nst
indi rect contact)
I EC 61 01 0-1 : 201 0,
6. 5
6. 5. 1
General
I EC 61 01 0-1 : 201 0,
6. 5. 1
Protective bondi ng
I EC 61 01 0-1 : 201 0,
6. 5. 2
6. 5. 2
Modified for
m etering
Modified for
m etering
IEC 60255-27: 201 3,
5. 1 . 5. 1
References
m ade to
I EC 61 032: 1 997
Modified for
m etering
I EC 61 01 0-1 : 201 0,
6. 4
IEC 60255-27: 201 3,
5. 1 . 2
Modified for
m etering
I EC 62052-1 1 : 2003,
5. 2. 1
I EC 62052-21 : 2004,
5. 2. 1
I EC 62052-1 1 : 2003,
5. 4
I EC 62052-21 : 2004,
5. 4
– 1 72 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
I EC 61 01 0-1 ,
6. 5. 2. 1
6. 5. 2. 1
General
6. 5. 2. 2
I ntegrity of protective bondi ng
I EC 61 01 0-1 : 201 0,
6. 5. 2. 2
Modified for
m etering
6. 5. 2. 3
Protective con ductor term inal
I EC 61 01 0-1 : 201 0,
6. 5. 2. 3
Modified for
m etering
6. 5. 2. 4
I m pedance of protecti ve
bon din g of perm anentl y
connected eq uipm ent
I EC 61 01 0-1 : 201 0,
6. 5. 2. 5
Modified for
m etering
6. 5. 2. 5
Transform er protecti ve bond in g
screen
I EC 61 01 0-1 : 201 0,
6. 5. 2. 6
6. 5. 3
Suppl em entary insulati on and
rei nforced i nsulati on
I EC 61 01 0-1 : 201 0,
6. 5. 3
6. 5. 4
Protective im pedance
I EC 61 01 0-1 : 201 0,
6. 5. 4
6. 5. 5
Autom atic disconnection of the
suppl y
I EC 61 01 0-1 : 201 0,
6. 5. 5
6. 5. 6
Current- or voltage-lim iting
device
I EC 61 01 0-1 : 201 0,
6. 5. 6
6. 6
Con nection to external ci rcuits
6. 6. 1
General
I EC 61 01 0-1 : 201 0,
6. 6. 1
Modified for
m etering
6. 6. 2
Term inals for extern al circuits
I EC 61 01 0-1 : 201 0,
6. 6. 2
Modified for
m etering
6. 6. 3
Term inals for strand ed
conductors
6. 7
I nsulation requ irem ents
6. 7. 1
General – Electrical stresses,
overvol tages and overvoltage
categories
6. 7. 1 . 1
Electric stresses origi nati ng
from m ains
6. 7. 1 . 2
Protection ag ainst
overvoltages of atm ospheric
ori gin or due to switchi ng
6. 7. 1 . 3
Classification of im pulse
withstan d voltag es
(overvoltag e categories)
6. 7. 2
The n ature of insu lation
6. 7. 2. 1
General
I EC 61 01 0-1 : 201 0,
6. 7. 1 . 1
6. 7. 2. 2
Clearances
I EC 61 01 0-1 : 201 0,
6. 7. 1 . 2
6. 7. 2. 3
Creepage distances
I EC 61 01 0-1 : 201 0,
6. 7. 1 . 3
6. 7. 2. 4
Solid insu lation
I EC 61 01 0-1 : 201 0,
6. 7. 1 . 4
IEC 60255-27: 201 3,
5. 1 . 6. 2
Modified for
m etering
See 6. 9. 7
I EC 61 01 0-1 : 201 0,
6. 7. 1 . 1
I EC 60364-444: 2007
I EC 60364-444: 2007 443. 1 .
I EC 60364-444: 2007, 443. 2. 2
Modified for
m etering: broken
neutral
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 73 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
6. 7. 2. 5
Req uirem ents for insul ation
accordi ng to type of circuit
0
I nsulation requ irem ents for
m ains-circuits
6. 7. 3. 1
Nom inal voltages an d rated
im pulse voltages
I EC 61 01 0-1 : 201 0,
6. 7. 1 . 5 and An nex
K
With Table 6
add ed provi ding
an overview
Specific for
m etering
Clearances for m ains-circuits
IEC 60664-1 :2007,
Table F. 2
I EC 62052-1 1 : 2003,
5. 6
Table dri ven by
rated im pulse
voltage
6. 7. 3. 3
Creepage distances for m ainscircuits
IEC 60664-1 :2007,
Table F. 4
I EC 62052-21 : 2004,
5. 6
Table dri ven by
rationali zed
voltage
6. 7. 3. 4
Solid insu lation for m ainscircuits
6. 7. 3. 4. 1
General
I EC 61 01 0-1 : 201 0,
K. 1 . 3
6. 7. 3. 4. 2
Mould ed and potted parts
I EC 61 01 0-1 : 201 0,
K. 1 . 3. 2
6. 7. 3. 4. 3
I nner insul atin g layers of
pri nted wiri ng boards (PWBs)
I EC 61 01 0-1 : 201 0,
K. 1 . 3. 3.
6. 7. 3. 4. 4
Thin -film insulation
I EC 61 01 0-1 : 201 0,
K. 1 . 3. 4.
6. 7. 4
I nsulation requ irem ents for
non-m ains-circuits
6. 7. 4. 1
General
6. 7. 4. 2
Clearances for non -mainscircuits
I EC 61 01 0-1 : 201 0,
K. 2. 2
6. 7. 4. 3
Creepage distances for non m ains-circuits
I EC 61 01 0-1 : 201 0,
K. 2. 3
6. 7. 4. 4
Solid insu lation for non-m ainscircuits
I EC 61 01 0-1 : 201 0,
K. 2. 4
6. 7. 4. 4. 1
General
I EC 61 01 0-1 : 201 0,
K. 2. 4. 1
6. 7. 4. 4. 2
Mould ed and potted parts
I EC 61 01 0-1 : 201 0,
K. 2. 4. 2
0
I nner insul atin g layers of
pri nted wiri ng boards
6. 7. 4. 4. 4
Thin -film insulation
I EC 61 01 0-1 : 201 0,
K. 2. 4. 4
6. 7. 5
I nsulation in circu its not
addressed i n 0 or 6. 7. 4
I EC 61 01 0-1 : 201 0,
Clause K. 3
6. 7. 5. 1
General
I EC 61 01 0-1 : 201 0,
K. 3. 1
6. 7. 5. 2
Clearance calcul ation
I EC 61 01 0-1 : 201 0,
K. 3. 2
6. 7. 5. 3
Clearances in circuits h avi ng
recu rri ng peak voltages, or
having working voltages with
freq uenci es above 30 kH z
I EC 61 01 0-1 : 201 0,
K. 3. 3
0
I EC 61 01 0-1 : 201 0,
K. 2. 4. 3
– 1 74 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
Creepage distances
I EC 61 01 0-1 : 201 0,
K. 3. 4
6. 7. 5. 5
Solid insu lation
I EC 61 01 0-1 : 201 0,
K. 3. 5
6. 7. 6
Reduction of transi ent
overvoltages by the use of
overvoltage lim iting devices
I EC 61 01 0-1 : 201 0,
Clause K. 4
6. 8
I nsulation requ irem ents
between ci rcuits and parts
IEC 60255-27: 201 3,
Annex A
6. 9
Construction al requ irem ents
for protection ag ainst el ectric
shock
I EC 61 01 0-1 : 201 0,
6. 9
6. 9. 1
General
I EC 61 01 0-1 : 201 0,
6. 9. 1
6. 9. 2
I nsulatin g m aterials
I EC 61 01 0-1 : 201 0,
6. 9. 2
6. 9. 3
Colour codin g
I EC 61 01 0-1 : 201 0,
6. 9. 3
0
6. 9. 4
Equipm ent case
6. 9. 5
Term inal bl ocks
6. 9. 6
I nsulatin g m aterials of su ppl y
control an d load switches
Modified for
m etering
Annex B
provi des m eter
specific
exam ples
I EC 62052-1 1 : 2003,
5. 7
I EC 62052-21 : 2004,
5. 7
I EC 62052-1 1 : 2003,
5. 2. 1
I EC 62052-21 : 2004,
5. 2. 1
Modified for
m etering
Modified for
m etering
I EC 62052-1 1 : 2003,
5. 4
I EC 61 01 0-1 : 201 0,
6. 6. 4
I EC 62052-21 : 2004,
5. 4.
6. 9. 7
Term inals
6. 9. 7. 1
General requi rem ents
6. 9. 7. 2
Connectin g capacity
I EC 62477-1 : 201 2,
4. 1 1 . 8. 2
6. 9. 7. 3
Reli ability of screw-type
connections
I EC 60947-1 : 2007,
8. 2. 4. 3
6. 9. 8
Req uirem ents for current
circuits
6. 9. 8. 1
Overview
6. 9. 8. 2
General
6. 9. 8. 2. 2
Rated operational voltage ( Ue )
I EC 60947-1 : 2007,
4. 3. 1 . 1
Modified for
m etering
6. 9. 8. 2. 3
Rated operation al current ( Ie )
I EC 60947-1 : 2007,
4. 3. 2. 3
Modified for
m etering
6. 9. 8. 2. 4
Rated frequency
I EC 60947-1 : 2007,
4. 3. 3
6. 9. 8. 2. 5
Rated uni nterrupted current
( Iu )
I EC 60947-1 : 2007,
4. 3. 2. 4
6. 9. 8. 2. 6
Uninterru pted duty
I EC 60947-1 : 2007,
4. 3. 4. 2
I EC 62477-1 : 201 2,
4. 1 1 . 8.
Specific for
m etering
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 75 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
6. 9. 8. 2. 7
Rated m aking capacity ( Im )
I EC 60947-1 : 2007,
4. 3. 5. 2
Modified for
m etering
6. 9. 8. 2. 8
Rated breakin g capacity ( Ic )
I EC 60947-1 : 2007,
4. 3. 5. 3
Modified for
m etering
6. 9. 8. 2. 9
Rated safe short-tim e
withstan d current ( Issw )
I EC 60947-1 : 2007,
4. 3. 6. 1
Modified for
m etering
6. 9. 8. 2. 1 0
Rated operation al short-tim e
withstan d current ( Io sw )
6. 9. 8. 2. 1 1
Rated short-circuit m aking
capacity ( Is m )
I EC 60947-1 : 2007,
4. 3. 6. 2
6. 9. 8. 2. 1 2
Rated conditi on al safe shortcircuit current ( Icssw )
I EC 60947-1 : 2007,
4. 3. 6. 4
6. 9. 8. 2. 1 3
Rated conditi on al operational
short-ci rcuit current ( Ico sw )
–
6. 9. 8. 3
Current circuits of di rect
connected m eters
6. 9. 8. 4
Current circuits of di rect
connected m eters with SCS
I EC 62055-31 : 2005,
Annex C
6. 9. 8. 5
Load control switches
I EC 62052-21 : 2004,
7. 4
6. 1 0
Safety related el ectrical tests
6. 1 0. 1
Overview
6. 1 0. 2
Test m ethods
6. 1 0. 2. 1
Atm ospheric conditi ons
6. 1 0. 2. 2
Test leads
6. 1 0. 2. 3
I m pulse voltage test
6. 1 0. 2. 4
Surg e test
6. 1 0. 2. 5
AC power-freq uency voltag e
test
I EC 61 1 80-1 : 1 992,
5. 2
6. 1 0. 2. 6
DC voltage test
I EC 61 1 80-1 : 1 992,
4. 2
6. 1 0. 2. 7
Altitude correcti on for testing
clearances
I EC 61 01 0-1 : 201 0,
6. 8. 1
6. 1 0. 3
Testing of voltage circuits
–
Modified for
m etering
–
Figu re 1 0
provi des a test
flowchart
I EC 60068-1 : 201 3,
4. 2
See 4. 3. 1 .
See 4. 3. 2. 1 1 .
I EC 61 1 80-1 : 1 992,
6. 2
I EC 61 000-45: 201 4, Cl ause 8
–
6. 1 0. 3. 1
Overview
–
6. 1 0. 3. 2
Lon g term overvol tage
withstan d
–
6. 1 0. 3. 3
I m pulse voltage test with out
suppl y voltag e
–
6. 1 0. 3. 4
Surg e test with suppl y voltag e
–
I EC 62052-1 1 : 2003,
7. 3. 2. 1
I EC 62052-21 : 2004,
7. 3. 2. 1
I EC 62055-31 : 2005,
7. 2. 3
I EC 62052-1 1 : 2003,
7. 3. 2. 1
I EC 62052-21 : 2004,
7. 3. 2. 1
–
Specific for
m etering
– 1 76 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
6. 1 0. 3. 5
I m pulse voltage test with SPDs
not present
6. 1 0. 4
Diel ectric tests
6. 1 0. 4. 1
Testing com plete equi pm ent
vs. sub-assem blies
6. 1 0. 4. 2
Hum idity preconditi oni ng
6. 1 0. 4. 3
Diel ectric test on com plete
equi pm ent
6. 1 0. 4. 3. 1
Test m ethods
6. 1 0. 4. 3. 2
Preparation of the m eteri ng
equi pm ent for testin g
6. 1 0. 4. 3. 3
The im pulse voltage test
–
–
–
–
I EC 61 01 0-1 : 201 0,
6. 8. 2
–
I EC 61 01 0-1 : 201 0,
6. 8. 1
–
I EC 62052-1 1 : 2003,
7. 3
I EC 62052-21 : 2004,
7. 3
I EC 62052-1 1 : 2003,
7. 3. 1
I EC 62052-21 : 2004,
7. 3. 1
I EC 62052-1 1 : 2003,
7. 3. 2. 1 , 7. 3. 2. 2
I EC 62052-21 : 2004,
7. 3. 2. 1 , 7. 3. 2. 2
6. 1 0. 4. 3. 4
The AC power-frequ ency
voltage test
6. 1 0. 4. 4
Diel ectric tests on subassem blies
6. 1 0. 4. 4. 1
Overview
6. 1 0. 4. 4. 2
Verification of clearances in
m ains circuits
6. 1 0. 4. 4. 2. 1
I m pulse voltage test
IEC 60664-1 :2007,
6. 1 . 2. 2. 1
6. 1 0. 4. 4. 2. 2
AC power-freq uency voltag e
test
IEC 60664-1 :2007,
6. 1 . 2. 2. 2
6. 1 0. 4. 4. 2. 3
DC voltage test
IEC 60664-1 :2007,
6. 1 . 2. 2. 3
6. 1 0. 4. 4. 3
Verification of clearances in
non -m ains-circuits
6. 1 0. 4. 4. 4
Verification of soli d insul ation
6. 1 0. 4. 4. 4. 1
General
6. 1 0. 4. 4. 4. 2
I m pulse voltage test
IEC 60664-1 :2007,
6. 1 . 3. 3
6. 1 0. 4. 4. 4. 3
The 5 s a. c. power-freq uency
voltage test
IEC 60664-1 :2007,
6. 1 . 3. 4
6. 1 0. 4. 4. 4. 4
The 1 m in a. c. voltage test
6. 1 0. 4. 4. 4. 5
The 1 m in d. c. voltage test
IEC 60664-1 :2007,
6. 1 . 3. 6
6. 1 0. 4. 4. 4. 6
Pass / fail criteria
IEC 60664-1 :2007,
6. 1 . 3. 3. 2
–
IEC 60664-1 :2007,
6. 1 . 1 , 6. 1 . 2
I EC 62053-1 1 : 2003,
7. 4
I EC 62053-21 : 2003,
7. 4
Modified for
m etering
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 77 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
6. 1 0. 4. 4. 5
Diel ectric tests in circuits
specified i n 6. 7. 5 – Verificati on
of clearances in circuits with
special overvoltage val ues
6. 1 0. 5
Electrical tests on current
circuits of direct connected
m eters without su ppl y control
switch es (SCSs)
6. 1 0. 6
Electrical tests on current
circuits of direct connected
m eters with SCSs
6. 1 0. 6. 1
Test sequence an d sam ple
plan
0
–
I EC 62055-31 : 2005,
Clause C. 9
Modified
Pre-conditi oni ng
6. 1 0. 6. 3
Switch ing th e n eutral by the
suppl y control switch
6. 1 0. 6. 4
Endu rance / n um ber of
operati ng cycles
I EC 62055-31 : 2005,
Clause C. 3
Modified
6. 1 0. 6. 5
Surg e voltag e withstand across
open contacts
I EC 62055-31 : 2005,
Clause C. 4
Modified
6. 1 0. 6. 6
Verification of the abil ity to
carry the rated safe short-tim e
withstan d current
I EC 62055-31 : 2005,
Clause C. 6
Modified
6. 1 0. 6. 7
Verification of the abil ity to
carry the rated operational
short-tim e withstand cu rrent
I EC 62055-31 : 2005,
Clause C. 6
Modified
6. 1 0. 6. 8
Verification of the abil ity to
m ake the rated short-circuit
current
I EC 62055-31 : 2005,
Clause C. 5
Modified
6. 1 0. 6. 9
Min im um switched current
(pass / fail criterion
I EC 62055-31 : 2005,
Clause C. 7
Modified
6. 1 0. 6. 1 0
Power consum ption (pass / fail
criteri on )
I EC 62055-31 : 2005,
7. 3. 2
Modified
6. 1 0. 6. 1 1
Diel ectric test (pass / fail
criteri on )
6. 1 0. 7
Electrical tests on load control
switch es
6. 1 0. 7. 1
Test sequence an d sam ple
plan
6. 1 0. 7. 2
Pre-conditi oni ng
6. 1 0. 7. 3
Endu rance / n um ber of
operati ng cycles
I EC 62052-21 : 2004,
7. 4. 3. 2
6. 1 0. 7. 4
Verification of the abil ity to
carry the rated con ditional safe
short-ci rcuit current ( Ic ssw )
I EC 62052-21 : 2004,
7. 4. 4. 2
6. 1 0. 7. 5
Verification of the abil ity to
carry the rated con ditional
operati onal short-circuit cu rren t
( Ico sw )
I EC 62052-21 : 2004,
7. 4. 4. 2
6. 1 0. 7. 6
Power consum ption (pass / fail
criteri on )
I EC 62052-21 : 2004,
7. 4. 3. 2
I EC 62055-31 : 2005,
Corr. 1
Clause C. 8
–
See 0.
– 1 78 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
I EC 62052-21 : 2004,
7. 4. 3. 2
6. 1 0. 7. 7
Diel ectric test (pass / fail
criteri on )
7
Protection ag ainst m echanical
hazards
7. 1
General
I EC 61 01 0-1 : 201 0,
7. 1
7. 2
Sharp ed ges
I EC 61 01 0-1 : 201 0,
7. 2
7. 3
Provisions for lifting and
carryin g
I EC 61 01 0-1 : 201 0,
7. 5
8
Resistance to m echanical
stresses
8. 1
General
8. 2
Sprin g ham m er test
9
Protection ag ainst spread of
fire
9. 1
Modified for
m etering
Modified for
m etering
I EC 60068-275: 201 4, Clause 6
I EC 62052-1 1 : 2003,
5. 2. 2. 1
General
I EC 61 01 0-1 : 201 0,
9. 1
I EC 62055-1 1 : 2003,
5. 8
9. 2
Elim inating or reducin g the
sources of ig nition within th e
equi pm ent
I EC 61 01 0-1 : 201 0,
9. 2
9. 3
Containm ent of fire with in the
equi pm ent, shoul d it occur
I EC 61 01 0-1 : 201 0,
9. 3
9. 3. 1
General
I EC 61 01 0-1 : 201 0,
9. 3. 1
9. 3. 2
Construction al requ irem ents
9. 3. 2. 1
Term inal bl ock, term inal cover,
case
9. 3. 2. 2
Con nectors and i nsulati on
m aterials on which com ponents
are m ounted
I EC 61 01 0-1 : 201 0,
9. 3. 2
9. 4
Lim ited-energ y circuit
I EC 61 01 0-1 : 201 0,
9. 4
Overcurrent protection
I EC 61 01 0-1 : 201 0,
9. 6. 2
0
Modified for
m etering
I EC 62055-1 1 : 2003,
5. 8
I EC 62052-1 1 : 2003,
5. 8
10
Equipm ent tem perature lim its
and resistance to heat
1 0. 1
Surface tem peratu re lim its for
protection agai nst bu rns
I EC 61 01 0-1 : 201 0,
1 0. 1
1 0. 2
Tem peratu re lim its for
term inals
I EC 60947-1 : 2007,
Table 2
1 0. 3
Tem peratu res of i nternal parts
I EC 62477-1 : 201 2,
4. 6. 4. 1
1 0. 4
Tem peratu re test
I EC 62477-1 : 201 2,
5. 2. 3. 1 0
1 0. 5
Resistance to heat
1 0. 5. 1
Non-m etallic enclosu res
I EC 61 01 0-1 : 201 0,
1 0. 5. 2
1 0. 5. 2
I nsulatin g m aterials
I EC 61 01 0-1 : 201 0,
1 0. 5. 3
Modified for
m etering
I EC 62052-1 1 : 2003,
7. 2
I EC 62055-1 1 : 2003,
7. 2
I EC 62052-1 1 : 2003,
5. 4
Modified for
m etering
I EC 62052-31 :201 5 © I EC 201 5
Cl au s e
Ti tl e
– 1 79 –
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
11
Protection ag ainst penetration
of dust an d water
I EC 60529: 1 989
12
Protection ag ainst liberated
gases an d substances
expl osion an d im plosion –
Batteries and battery ch arging
I EC 61 01 0-1 : 201 0,
1 1 . 5, 1 3. 2. 2
13
Com ponents and su bassem blies
1 3. 1
General
I EC 61 01 0-1 : 201 0,
1 4. 1
1 3. 2
Mai ns transform ers tested
outside equ ipm ent
I EC 61 01 0-1 : 201 0,
1 4. 6
1 3. 3
Printed wi rin g boards
I EC 61 01 0-1 : 201 0,
1 4. 7
1 3. 4
Com ponents bri dgi ng
insulati on
I EC 62477-1 : 201 2,
4. 4. 7. 1 . 7
1 3. 5
Circuits or com ponents used
as transient overvoltag e
lim iting devices
I EC 61 01 0-1 : 201 0,
Clause K. 4.
14
Hazards resu lting from
appl ication – Reason abl y
foreseeable m isuse
I EC 61 01 0-1 : 201 0,
1 6. 1
15
Risk assessm ent
I EC 61 01 0-1 : 201 0,
Clause 1 7
(norm ative)
Annex A
Measuri ng circuits for touch
current
I EC 62052-1 1 : 2003,
5. 9. .
I EC 6025527: 201 3, 8. 7. 2. 2
Modified
I EC 61 01 0-1 : 201 0,
Annex A
(inform ative)
Annex B
Exam ples for insulati on
between parts
–
–
–
–
–
–
–
–
–
–
(inform ative)
Annex C
Exam ples for di rect con nected
m eters equipped with
suppl y control and l oad control
switch es
(norm ative)
Annex D
Test circuit diagram for th e test
of lon g term overvol tage
withstan d
(norm ative)
Annex E
Annex F
Test circuit diagram for short
current test on
the current circuit of di rect
connected m eters
(inform ative)
Exam ples for voltage tests
(norm ative)
Annex G
Additional a. c. voltage tests for
electrom echanical m eters
–
I EC 62053-1 1 : 2003,
7. 4
I EC 62053-21 : 2003,
7. 4
– 1 80 –
Cl au s e
Ti tl e
I EC 62052-31 :201 5 © I EC 201 5
S o u rc e fro m
h o ri z o n t a l
/
g ro u p o t h e r
p ro d u c t s a fe t y
s t a n d a rd s
S o u rc e fro m
TC 1 3
Re m a rk
t yp e t e s t
s t a n d a rd s :
I E C 6 2 0 5 2 -1 1 :
2003
I E C 6 2 0 5 2 -2 1 : 2 0 0 4
I E C 6 2 0 5 5 -3 1 : 2 0 0 5
(norm ative)
Annex H
Annex I
Annex J
Test equi pm ent for cabl e
flexi on and pull test
(inform ative)
Routi ne tests
(inform ative)
Exam ples of battery protection
I EC 60947-1 : 2007,
8. 2. 4. 3
I EC 61 01 0-1 : 201 0,
Annex F
Modified for
m etering
IEC 60255-27: 201 3,
Annex F
(inform ative)
Annex K
Rational e for specifyi ng
overvoltage category I I I
(inform ative)
Annex L
Annex M
Overview of safety aspects
covered
(inform ative)
I ndex of d efined term s
This Annex
I EC 62052-31 :201 5 © I EC 201 5
– 1 81 –
An n e x M
(informative)
I n d e x o f d e fi n e d te rm s
accessible part
3. 5. 1
am bient air tem perature
3. 3. 5
au xiliary circuit
3. 5. 1 1
au xiliary control switch
3. 7. 4
au xiliary device
3. 5. 1 0
au xiliary suppl y
3. 5. 9
base
3. 2. 3
basic insulati on
3. 6. 3
breaking capacity (of a switchi ng d evice or a fuse)
3. 7. 9
breaking cu rrent (of a switchi n g device or a fuse)
3. 7. 8
case
3. 2. 5
(protecti ve) cl ass I equipm ent
3. 6. 7
(protecti ve) cl ass I I equipm ent
3. 6. 8
clearance
3. 6. 1 5
cover
3. 2. 4
creepag e distance
3. 6. 1 6
current circuit
3. 5. 4
direct contact
3. 5. 1 7
disru ptive discharg e
3. 6. 1 8
dou ble i nsulati on
3. 6. 5
(local ) earth
3. 2. 1 0
electric insul ation
3. 6. 1
(el ectricall y) protective barri er
3. 2. 1
equi pm ent
3. 1 . 1
extra-low-voltage
3. 6. 22
ELV (abbrevi ation)
flashover
3. 6. 20
function al insul ation
3. 6. 2
fused short-circu it current
3. 7. 1 3
hazard
3. 5. 2
hazardous live
3. 5. 3
indi rect contact
3. 5. 1 8
indoor m eter
3. 2. 1 1
installer
3. 5. 21
isolation
3. 1 . 4
load control switch
3. 7. 3
m ains
3. 5. 6
m ains-circuit
3. 5. 7
m aking capacity (of a switchi n g device or a fuse)
3. 7. 1 0
m axim um current ( Ima x )
3. 3. 1 0
– 1 82 –
I EC 62052-31 :201 5 © I EC 201 5
m axim um overl oad current ( Io vl )
3. 3. 1 1
m axim um total current, I tot
3. 7. 5
m eter cabinet
3. 2. 1 4
m icro-en vironm ent
3. 6. 1 4
m inim um switched current
3. 7. 1 4
non -m ains-circuit
3. 5. 8
norm al con dition
3. 5. 1 5
norm al use
3. 5. 1 4
operati ng ran ge
3. 3. 3
operator
3. 5. 22
outdoor m eter
3. 2. 1 2
overvoltage category
3. 5. 26
packagi ng
3. 2. 1 6
PELV system
3. 6. 24
perm anentl y conn ected equi pment
3. 1 . 2
poll ution
3. 6. 9
poll ution degree
3. 6. 1 0
poll ution degree 1
3. 6. 1 1
poll ution degree 2
3. 6. 1 2
poll ution degree 3
3. 6. 1 3
prospective current (of a circuit with or with out a switchi ng device)
3. 7. 7
protective bon din g
3. 5. 1 3
protective cond uctor term inal
3. 2. 8
protective im ped ance
3. 5. 1 2
punctu re
3. 6. 21
rated im pulse voltag e
3. 3. 8
rated m axim um am bient tem perature, ta
3. 3. 6
rated valu e
3. 3. 1
rated voltag e
3. 3. 4
ratin g
3. 3. 2
reasonably foreseeable m isuse
3. 5. 23
reference earth
3. 2. 9
rei nforced insul ation
3. 6. 6
restricted access area
3. 2. 2
risk
3. 5. 24
routi ne test
3. 4. 2
SELV system
3. 6. 23
service person
3. 5. 20
short-ci rcuit current
3. 7. 6
short-ci rcuit m aking capacity
3. 7. 1 1
short-tim e withstand cu rrent
3. 7. 1 2
single fault cond ition
3. 5. 1 6
solid insul ation
3. 6. 1 7
sparkover
3. 6. 1 9
specified m atching socket
3. 2. 1 5
I EC 62052-31 :201 5 © I EC 201 5
– 1 83 –
supplem entary insul ation
3. 6. 4
suppl y control switch
3. 7. 2
(m echanical ) switch
3. 7. 1
tem porary overvoltage
3. 5. 28
term inal
3. 2. 7
term inal cover
3. 2. 6
tolerabl e risk
3. 5. 25
tool
3. 1 . 3
transient overvoltage
3. 5. 27
trip-free m echanical switchi ng device
3. 7. 1 5
type test
3. 4. 1
user
3. 5. 1 9
utilization categ ory
3. 3. 9
venti lated, adj
3. 2. 1 3
voltage ci rcuit
3. 5. 5
worki ng voltage
3. 3. 7
– 1 84 –
I EC 62052-31 :201 5 © I EC 201 5
Bibliography
I EC Guide 1 04: 201 0, The preparation of safety publications and the use of basic safety
publications and group safety publications
I SO/I EC Guide 51 : 201 4, Safety aspects – Guidelines for their inclusion in standards
I EC 60038, Standard voltages
I EC 60050-441 : 1 984, International Electrotechnical Vocabulary – Part 441: Switchgear,
controlgear and fuses
I EC 60060-1 : 201 0, High-voltage test techniques – Part 1: General definitions and test
requirements
I EC 60065, Audio, video and similar electronic apparatus – Safety requirements
I EC 60068-1 : 201 3, Environmental testing – Part 1: General and guidance
I EC 60071 -1 , Insulation co-ordination – Part 1: Definitions, principles and rules
I EC 60079-0, Explosive atmospheres – Part 0: Equipment – General requirements
IEC 60228, Conductors of insulated cables
IEC 60255-27: 201 3, Measuring relays and protection equipment – Part 27: Product safety
requirements
IEC 60269-1 , Low-voltage fuses – Part 1: General requirements
I EC 60335-1 , Household and similar electrical appliances – Safety – Part 1: General
requirements
IEC 60364-1 : 2005, Low-voltage electrical installations – Part 1: Fundamental principles,
assessment of general characteristics, definitions
I EC 60364-4-41 , Low-voltage electrical installations – Part 4-41: Protection for safety –
Protection against electric shock
I EC 60364-5-52, Low-voltage electrical installations – Part 5-52: Selection and erection of
electrical equipment – Wiring systems
IEC TR 60664-2-1 , Insulation coordination for equipment within low-voltage systems –
Part 2-1: Application guide – Explanation of the application of the IEC 60664 series,
dimensioning examples and dielectric testing
IEC 60664-3:2003, Insulation coordination for equipment within low-voltage systems – Part 3:
Use of coating, potting or moulding for protection against pollution
Am d 1 : 201 0
IEC 60688: 201 2, Electrical measuring transducers for converting a.c. electrical quantities to
analogue or digital signals
I EC 62052-31 :201 5 © I EC 201 5
– 1 85 –
I EC 60721 -3-0: 1 984, Classification of environmental conditions – Part 3: Classification of
groups of environmental parameters and their severities – Introduction
Amd 1 : 1 987
IEC 60721 -3-3: 1 994, Classification of environmental conditions – Part 3-3: Classification of
groups of environmental parameters and their severities – Stationary use at weatherprotected
locations
Amd 1 : 1 995
Amd 2: 1 996
IEC 60898-1 : 201 5, Electrical accessories – Circuit breakers for overcurrent protection for
household and similar installations – Part 1: Circuit-breakers for a.c. operation
IEC 60947-1 : 2007, Low-voltage switchgear and controlgear – Part 1: General rules
Am d 1 : 201 0
Am d 2: 201 4
I EC 60990, Methods of measurement of touch current and protective conductor current
IEC 61 008-1 , Residual current operated circuit-breakers without integral overcurrent
protection for household and similar uses (RCCBs) – Part 1: General rules
IEC 60990, Methods of measurement of touch current and protective conductor current
IEC TR 61 000-2-3: 1 992, Electromagnetic compatibility (EMC) – Part 2: Environment – Section
3: Description of the environment – Radiated and non-network-frequency-related conducted
phenomena
I EC TR 61 000-2-1 4, Electromagnetic compatibility (EMC) – Part 2-14: Environment –
Overvoltages on public electricity distribution networks
I EC 61 000-4-5: 201 4, Electromagnetic compatibility (EMC) – Part 4-5: Testing and
measurement techniques – Surge immunity test
IEC 61 01 0-1 : 201 0, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 1: General requirements
IEC 61 01 0-2-030, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 2-030: Particular requirements for testing and measuring circuits
IEC 61 051 -2, Varistors for use in electronic equipment – Part 2: Sectional specification for
surge suppression varistors
IEC 61 1 40, Protection against electric shock – Common aspects for installation and
equipment
I EC 61 1 80-1 : 1 992, High-voltage test techniques for low voltage equipment – Part 1:
Definitions, test and procedure requirements
IEC 61 558-1 , Safety of power transformers, power supplies, reactors and similar products –
Part 1: General requirements and tests
IEC 61 558-2-1 6, Safety of transformers, reactors, power supply units and similar products for
supply voltages up to 1 100 V – Part 2-16: Particular requirements and tests for switch mode
power supply units and transformers for switch mode power supply units
– 1 86 –
I EC 62052-31 :201 5 © I EC 201 5
I EC 61 643-1 2, Low-voltage surge protective devices – Part 12: Surge protective devices
connected to low-voltage power distribution systems – Selection and application principles
IEC 61 869-3, Instrument transformers – Part 3: Additional requirements for inductive voltage
transformers
IEC 62052-1 1 :2003, Electricity metering equipment (a.c.) – General requirements, tests and
test conditions – Part 11: Metering equipment
I EC 62052-21 :2004, Electricity metering (a.c.) – General requirements, tests and test
conditions – Part 21: Tariff and load control equipment
IEC 62053-1 1 : 2003, Electricity metering equipment (a.c.) – Particular requirements – Part 11:
Electromechanical meters for active energy (classes 0, 5, 1 and 2)
IEC 62053-21 :2003, Electricity metering equipment (a.c.) – Particular requirements – Part 21:
Static meters for active energy (classes 1 and 2)
I EC 62053-22:2003, Electricity metering equipment (a.c.) – Particular requirements – Part 22:
Static meters for active energy (classes 0,2 S and 0,5 S)
I EC 62053-23: 2003, Electricity metering equipment (a.c.) – Particular requirements – Part 23:
Static meters for reactive energy (classes 2 and 3)
IEC 62053-24: 201 4, Electricity metering equipment (a.c.) – Particular requirements – Part 24:
Static meters for reactive energy at fundamental frequency (classes 0, 5 S, 0, 5, 1S and 1)
I EC 62053-31 :1 998, Electricity metering equipment (a.c.) – Particular requirements – Part 31:
Pulse output devices for electromechanical and electronic meters (two wires only)
I EC 62054-1 1 :2004, Electricity metering (a.c.) – Tariff and load control – Part 11: Particular
requirements for electronic ripple control receivers
I EC 62054-21 :2004, Electricity metering (a.c.) – Tariff and load control – Part 21: Particular
requirements for time switches
IEC 62055-31 :2005, Electricity metering – Payment systems – Part 31: Particular
requirements – Static payment meters for active energy (classes 1 and 2)
I EC 62058-1 1 :2008, Electricity metering equipment (AC) – Acceptance inspection – Part 11:
General acceptance inspection methods
IEC 62058-21 :2008, Electricity metering equipment (AC) – Acceptance inspection – Part 21:
Particular requirements for electromechanical meters for active energy (classes 0, 5, 1 and 2)
IEC 62058-31 : 2008, Electricity metering equipment (AC) – Acceptance inspection – Part 31:
Particular requirements for static meters for active energy (classes 0,2 S, 0,5 S, 1 and 2)
I EC 62477-1 : 201 2, Safety requirements for power electronic converter systems and
equipment – Part 1: General
ISO 780, Packaging – Pictorial marking for handling of goods
ISO 701 0, Graphical symbols – Safety colours and safety signs – Registered safety signs
I EC 62052-31 :201 5 © I EC 201 5
– 1 87 –
EN 563, Safety of machinery. Temperatures of touchable surfaces. Ergonomics data to
establish temperature limit values for hot surfaces
CEN ELEC Guide 29, Temperatures of hot surfaces likely to be touched. Guidance document
for Technical Committees and manufacturers
DI N 46228-1 :1 992-08, Aderendhülsen; Rohrform ohne Kunststoffhülse (English: Tubular endsleeves without plastic sleeve)
ASTM B258 – 02, Standard Specification for Standard Nominal Diameters and Cross-
Sectional Areas of AWG Sizes of Solid Round Wires Used as Electrical Conductors
UL 1 439, Standard for Safety Tests for Sharpness of Edges on Equipment
UL 2556, Wire and Cable Test Methods
_____________
INTERNATIONAL
ELECTROTECHNICAL
COMMISSI ON
3, rue de Varembé
PO Box 1 31
CH-1 21 1 Geneva 20
Switzerland
Tel: + 41 22 91 9 02 1 1
Fax: + 41 22 91 9 03 00
info@iec.ch
www.iec.ch