TS Traffic Installation Testing
Siemens Mobility Division Traffic Solutions
667/HE/20664/000
Sopers Lane
Poole
Dorset
BH17 7ER
SYSTEM/PROJECT/PRODUCT: Traffic Signals
INSTALLATION AND
COMMISSIONING HANDBOOK
INSTALLATION TESTING
(GENERAL)
Prepared: David Martin
Approved: D.A.Martin
Function: Engineering Manager
Function: Engineering Manager
THIS DOCUMENT IS ELECTRONICALLY APPROVED
AND HELD IN THE TS DOCUMENT CONTROL TOOL
Issue :
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Change Ref :
83/16446
83/16563
83/16700
ANL00102
TS000669
TS001616
TS004023
TS004922
TS004944
TS005821
TS007220
TS008004
TS008072
Date :
5/7/89
28/4/92
22/6/92
14/9/93
13/11/96
January 1999
February 2001
September 2001
February 2003
October 2003
December 2003
September 2007
February 2009
November 2009
December 2012
December 2014
June 2015
July 2015
This is an unpublished work the copyright in which vests in Siemens plc. All rights reserved.
The information contained herein is the property of Siemens plc. and is supplied without liability for errors or omissions. No
part may be reproduced or used except as authorised by contract or other written permission. The copyright and the
foregoing restriction on reproduction and use extend to all media in which the information may be embodied.
667/HE/20664/000
Page
1
Issue 18
TS Traffic Installation Testing
SAFETY WARNING
HEALTH AND SAFETY AT WORK
Note by the Health and Safety at Work Executive
BS 7671 and the IET Wiring Regulations have been extensively referred to in HSE guidance
over the years. Installations which conform to the standards laid down in BS 7671:2008 (and
incorporating amendments) are regarded by HSE as likely to achieve conformity with the
relevant parts of the Electricity at Work Regulations 1989. Existing installations may have
been designed and installed to conform to the standards set by earlier editions of BS 7671 or
the IET Wiring Regulations. This does not mean that they will fail to achieve conformity with
the relevant parts of the Electricity at Work Regulations 1989.
Safety of Installation and Maintenance Personnel
In the interests of health and safety, when installing, using or servicing this equipment the
following instructions must be noted and adhered to:
(i)
Prior to any work being started a Risk Assessment must be completed.
(ii)
Only competent persons who possess sufficient technical knowledge, relevant
practical skills and experience for the nature of the electrical work undertaken and
are able to prevent danger and, when appropriate, injury to themselves and others,
and who are also familiar with the safety procedures required when dealing with
modern electrical/electronic equipment are to be allowed to use and/or work on the
equipment. All work shall be performed in accordance with the Electricity at Work
Regulations 1989.
(iii)
Electrical equipment shall be selected so as to withstand safely the stresses, the
environmental conditions and the characteristics of its location. An item of equipment
which does not by design have the properties corresponding to its location may be
used where adequate further protection is provided as part of the completed
electrical installation. As a minimum all equipment must be H.A. approved.
(iv)
Good workmanship by competent persons or persons under their supervision and
proper materials shall be used on the erection of the electrical installation. Electrical
equipment shall be installed in accordance with the instructions provided by the
manufacturer of the equipment.
(v)
Competent personnel must take heed of all relevant notes, cautions and warnings in
this Handbook and any other Document or Handbook associated with the equipment
including, but not restricted to, the following:
(a) The equipment must be correctly connected to the specified incoming power
supply and earth protection installed and tested in accordance with current BS
7671 Wiring Regulations.
(b) The equipment must be disconnected / isolated from the incoming power supply
before removing any protective covers or working on any part from which the
protective covers have been removed.
(c) Any power tools and equipment must be regularly inspected and tested.
(d) Any ladders used must be inspected before use to ensure they are sound and
not damaged.
667/HE/20664/000
Page
2
Issue 18
TS Traffic Installation Testing
(e) When using a ladder, before climbing it, ensure that it is erected properly and is
not liable to collapse or move. If using a ladder near a carriageway ensure that
the area is properly coned and signed.
(f)
(vi)
Any personnel working on site must wear the appropriate protective clothing,
e.g. reflective vests, etc
When competent personnel are working within a confined space with restricted
movement the following protective measures apply to circuits supplying the following
current-using equipment:
(a) For the supply to a hand-held tool or an item of mobile equipment:
i. Electrical separation subject to only one item of equipment being connected
to a secondary winding of the transformer or
ii. SELV
(b) For the supply to hand lamps:
i. SELV. It is permissible for the SELV circuit to supply a fluorescent luminaire
with a built-in step-up transformer with electrically separated windings.
(c) For the supply to fixed equipment:
i. Automatic disconnection of the supply with supplementary equipotential
bonding. The supplementary bonding shall connect exposed-conductive
parts of fixed equipment and the conductive parts of the location, or
ii. By use of Class II equipment or equipment having equivalent insulation
provided the supply circuits have additional protection by the use of RCDs
having the characteristics specified in BS 7671,or
iii. Electrical separation subject to only one item of equipment being connected
to secondary winding of the isolating transformer, or
iv. SELV, or
v. PELV, where equipotential bonding is provided between all exposedconductive-parts, all extraneous-conductive-parts inside the conducting
location with restricted movement, and the connection of the PELV system
to Earth.
Safety of Road Users
It is important that all personnel are aware of the dangers to road users that could arise during
installation, repair and maintenance of traffic control equipment.
Ensure that the junction area is coned and signed as necessary. Barriers and suitable
warning signals/signs must be in place prior to work commencing and arranged to give clear
warning to motorists and pedestrians of the electrical or mechanical hazards relating to the
work being carried out on the traffic installation. Ensure adherence to safety requirements
conforming to current BS 7671 17th Edition Wiring Regulations to help protect the personnel
working on the site. (16th edition section 611”Highway Power Supplies” is now 17th section
559.10).
Whilst repairing signals which are in an "all-out" condition, care must be taken to ensure that
no spurious signals are lit during testing which could mislead drivers or pedestrians.
Particular care is required where pedestrian audible devices are installed, to ensure that no
false indications are given during, for example, cable testing. Personnel should also ensure
667/HE/20664/000
Page
3
Issue 18
TS Traffic Installation Testing
the safety of pedestrians, especially children, who may come into contact with the equipment
metalwork.
667/HE/20664/000
Page
4
Issue 18
TS Traffic Installation Testing
CONTENTS
SAFETY WARNING
2
1.
7
1.1
1.2
1.3
1.4
1.5
2.
INTRODUCTION
PURPOSE
SCOPE
RELATED DOCUMENTS
QUALIFICATIONS
GLOSSARY
7
7
8
9
10
INSTALLATION TESTING
12
2.1 TEST GEAR REQUIREMENT
12
2.2 CORE TO CORE TESTING
12
2.2.1
Equipment
13
2.2.2
Method
13
2.3 VISUAL INSPECTION
14
2.4 CIRCUIT PROTECTIVE CONDUCTOR (CPC) TEST
14
2.4.1
Provision of cable cores for test purposes
15
2.4.2
Loop Resistance of Two “Test” Cable Cores on Each Cable Run
15
2.4.3
Loop Resistance of Cable Core (R1) and CPC (R2). For Poles without push buttons. 15
2.4.4
Loop Resistance of Cable Core and CPC. For Poles with push buttons.
16
2.4.5
CPC Continuity Resistance
16
2.5 BASIC POLARITY TEST (ADDITIONAL)
17
2.6 SITE INSULATION TEST
18
2.6.1
Preparation
18
2.6.2
Test
19
2.7 POLARITY TEST
20
2.8 EARTH LOOP IMPEDANCE TESTS (ZS)
23
2.8.1
General Information
23
2.8.2
Preparation
24
2.8.3
Fuse Replacement
27
2.8.4
Measuring Earth Loop Impedance at The Origin, Prospective Short Circuit Current and Prospective
Fault Current.
27
2.8.5
Measuring Earth Loop Impedance at Poles and Push buttons in LV installations
28
2.8.6
Calculating the ELI value for ELV only poles
29
2.8.7
Measuring Earth Loop Impedance within the Controller Cabinet
29
2.8.8
Controller RCD Fitted To Incoming Power
30
2.8.9
Maximum Allowable Earth Loop Impedance With in-line RCD
30
2.9 RCD TEST
30
2.9.1
30mA Trip Current RCD Protecting Maintenance Socket
30
2.9.2
300 mA RCD Protecting Whole Installation (If fitted)
31
2.10 DETECTOR LOOP TEST
31
2.10.1
Tests
31
2.11 ADDITIONAL INSULATION TESTS
33
2.12 NEUTRAL CONDUCTOR VOLTAGE DROP TEST
33
2.13 GUIDANCE FOR GENERATORS
33
2.14 COMMISSIONING
34
2.15 VERIFICATION OF ELI RESULTS
34
2.16 COMPLETION OF CERTIFICATES
34
3.
3.1
TESTING TO CLEAR PROBLEMS
35
PURPOSE
35
667/HE/20664/000
Page
5
Issue 18
TS Traffic Installation Testing
3.2 TEST EQUIPMENT
35
3.3 TOTAL SITE/JUNCTION INSULATION TEST
36
3.3.1
Preparation
36
3.3.2
Test
36
3.4 EARTH LOOP IMPEDANCE TEST (ZS)
37
3.4.1
Preparation
37
3.4.2
Tests
37
3.4.3
Maximum Allowable Impedance (fuse protected)
38
3.4.4
Maximum Allowable Impedance (RCD protected)
38
3.4.5
Fuse Replacement
38
3.4.6
Signal Head Poles
38
3.5 TESTING OF RCDS
39
3.5.1
Preparation
39
3.5.2
30mA trip current RCD protecting maintenance socket
39
3.5.3
300mA RCD protecting whole controller (if fitted)
40
3.6 CORE INSULATION TESTING
40
3.6.1
Preparation
40
3.6.2
Test
40
3.7 CORE TO CORE LOOP RESISTANCE CONTROLLER TO POLE
40
3.7.1
Preparation
40
3.7.2
Tests
42
3.8 DC RESISTANCE CHECKS ON LAMP TRANSFORMERS (TS SUPPLIED SIGNAL HEADS ONLY)42
3.8.1
Preparation
42
3.8.2
Tests
42
3.9 NEUTRAL CONDUCTOR VOLTAGE DROP TEST
43
4.
4.1
4.2
5.
5.1
PERIODIC INSPECTION AND TESTING
44
INTRODUCTION
CONTENT OF WORK
44
44
MINOR WORKS
48
INTRODUCTION
48
APPENDIX A - PRECAUTIONS TO BE TAKEN WHEN PLANNING THE INSTALLATION
AND MAINTENANCE OF TRAFFIC CONTROL EQUIPMENT IN THE VICINITY OF LIGHT
RAPID TRANSPORT SYSTEMS.
49
APPENDIX B - COMPLETION CERTIFICATE AND TEST RESULTS
51
APPENDIX C - P.I. ELECTRIC TEST CERTIFICATE
61
APPENDIX D - MINOR ELECTRICAL INSTALLATION WORKS CERTIFICATE 71
APPENDIX E - START UP ROUTINE
667/HE/20664/000
Page
74
6
Issue 18
TS Traffic Installation Testing
1.
INTRODUCTION
1.1
PURPOSE
This handbook contains details of test procedures designed to verify functional aspects
of wiring and to ensure that an installation conforms to the requirements of the 17th
edition of the IET wiring regulations (BS7671:2008) incorporating the following
amendments:
Amendment No. 1:2011 (issued on 1st July 2011, and effective from 1st January 2012)
Amendment No. 2:2013 (issued on and effective from 1st August 2013)
Amendment No. 3:2015 (issued on 1st January 2015, and effective from 1st July 2015)
1.2
SCOPE
This handbook details testing procedures to be carried out as part of the installation for
traffic signal controllers, poles, signals and associated equipment. It should be read in
conjunction with the other Installation and Commissioning Handbooks - see section 1.3.
It also contains procedures for electrical tests performed during fault location and
routine maintenance visits but does not include service schedules, which are contained
in the appropriate controller manual.
Where a variance between Local Authority Specifications, Equipment Specifications
and this document exist, the Local Authority and Equipment Specifications take
precedence only when additional procedures or tests are identified. The resulting
degree of safety of the installation shall be not less than that obtained by compliance
with BS 7671 IET Wiring Regulations 17th edition.
Note that although this handbook is arranged in the order that tests would normally be
carried out, testing is not a continuous activity and takes place at various stages of
installation as required.
667/HE/20664/000
Page
7
Issue 18
TS Traffic Installation Testing
1.3
RELATED DOCUMENTS
Detectors and Cable Terminations Handbook
Above Ground Detectors Handbook
Helios Signals and Poles Handbook
ST4R Detector Handbook
ST700 General Handbook
ST900 General Handbook
ST750 General Handbook
ST750 ELV General Handbook
ST950 General Handbook
ST800 Installation Commissioning and Maintenance Handbook
ST900 Installation Commissioning and Maintenance Handbook
ST900 ELV Installation Commissioning & Maintenance Handbook
ST950 ELV Installation and Commissioning Handbook
ST950 LV Installation and Commissioning Handbook
UPS Solution General Handbook
Traffic Signal Junction Cabling Design Certification (LV)
Traffic Signal Junction Cabling Design Certification (ELV)
667/HE/20663/000
667/HE/20665/000
667/HB/30000/000
667/HB/27663/000
667/HB/27880/000
667/HB/32900/000
667/HB/33750/000
667/HB/32750/000
667/HB/46000/000
667/HE/27000/000
667/HE/33900/000
667/HE/32900/000
667/HE/45950/000
667/HE/46950/000
667/HB/47750/000
667/DS/20664/000
667/DS/20664/048
BS7671: AMD3: 2015 Requirements for Electrical Installations. IET Wiring regulations
17th Edition
BS 7430:2011 Code of practice for protective earthing of electrical installations (see
Section 7 covering Generators if applicable)
Guidance Note 3: Inspection and Testing (from the IET)
667/HE/20664/000
Page
8
Issue 18
TS Traffic Installation Testing
1.4
QUALIFICATIONS
Only skilled or instructed personnel with relevant technical knowledge and experience,
who are also familiar with the safety procedures required when dealing with modern
electrical/electronic equipment, are to be allowed to use and/or work on the equipment.
All work shall be performed in accordance with the Electricity at Work Regulations
1989 or the relevant local, state and government regulations.
Any personnel working on Siemens Traffic Controllers should have completed the
following training courses:
HA Sector Scheme Sector 8 Modules 5XX (for installation)
M609 – Junction Traffic Controller Maintenance
Any personnel completing and signing the certificates for installation and/or periodic
inspection must hold the relevant National Highway Sector Scheme modules.
Training requirements for non UK users may be different.
667/HE/20664/000
Page
9
Issue 18
TS Traffic Installation Testing
1.5
GLOSSARY
CET
Central Earth Termination
CPC
Circuit Protective Conductor
DNO
Distribution Network Operator
ELI
Earth Loop Impedance
ELV
Extra Low Voltage - Normally not exceeding 50 V a.c. or 120 V ripple-free
d.c., whether between conductors or to earth
FELV
Functional Extra Low Voltage
IET
Institute of Engineering and Technology (formerly IEE)
Line
A conductor of an a.c system for the transmission of electrical energy
other than a neutral conductor, a protective conductor or a PEN
conductor. The term also means the equivalent conductor of a d.c system
unless otherwise specified in the regulations.
Live
Live conductor defined as any live part of the installation intended to be
energised in normal use.
LRT
Light Rapid Transport
LV
Low Voltage – Normally exceeding extra low voltage but not exceeding
1000 V a.c. or 1500 V d.c. between conductors, or 600 V a.c. or 900 V
d.c. between conductors and Earth
MET
Main Earth Terminal
PEN
A conductor combining the functions of both protective conductor and
neutral conductor
PELV
Protective Extra Low Voltage. An extra low voltage system which is not
electrically separated from earth.
PI
Periodic Inspection
PME
Protective Multiple Earthing
PPE
Personal Protective Equipment
RCD
Residual Current Device (Residual Current Circuit Breaker).
STS
Site Traffic Signals
TS
Traffic Solutions (part of the Siemens Mobility Division)
TN-C supply Where the neutral and protective functions are combined in a single
conductor (known as PME).
TN-C-S
A system where the supply is TN-C (neutral and protective functions are
combined) and the arrangement of the system is TN-S (separate neutral
and protective conductors).
TT supply
Where no earth is provided by the supply authority and an earth electrode
is used as the method of earthing.
UPS
Uninterruptible Power Supply
Note:
667/HE/20664/000
Page
10
Issue 18
TS Traffic Installation Testing
For full definitions of FELV, PELV and ELV, see IET Regulations 17th Edition
(BS7671:2008 incorporating Amendment No 1:2011).
667/HE/20664/000
Page
11
Issue 18
TS Traffic Installation Testing
2.
INSTALLATION TESTING
2.1
TEST GEAR REQUIREMENT
General: Test equipment and their leads must conform to the safety
requirements as laid down in BS EN 61557 (Electrical safety in LV
systems) and BS EN 61010 (Safety requirements for electrical
equipment in measurement and control).
i) A Low resistance ohm meter, or the continuity range of an insulation and
continuity tester (see iii below). An instrument to BS EN 61557-4 will meet the
requirements expressed in BS7671.
ii) Digital Multimeter capable of reading 250V or greater,
current to (10A).
iii) Insulation Tester. Megger BM222 or similar.
iv) Earth Loop Impedance Tester. Megger LT5 or similar
v) RCD Tester capable of testing both positive and negative half cycles as
required in IET Regs 17th Edition. (e.g. Megger CBT3, Robin KMP 5404,
ISO TECH IRT 1900, Metrohm 16R, Seaward RC750).
vi) Inductance tester (LCR bridge). Wavetek DM27XT or Beckman LM22A or
similar.
vii) A test lamp certified to meet the requirements of the HSE, Guidance note
GS38 "Electrical test equipment for use by electricians". (This may be used in
place of a multimeter to check polarity).
For tests of earth electrode resistance where low values are required, it may be
necessary to use a four-terminal earth tester (e.g. for use with generators, see IET
Guidance Note 3: Inspection and Testing section 2.7.12).
Note that all test equipment must be within its calibration period.
Note: The following sections, 2.2 to 2.6 inclusive, must be completed
before connection to the mains supply.
2.2
CORE TO CORE TESTING
The test will ensure that the insulation of the cable has not been compromised during
the installation. It will also comply with minimum values obtained from table 61 of
BS7671 IET Wiring regulations 17th Edition for insulation resistance testing between
live conductors and each live conductor to earth.
667/HE/20664/000
Page
12
Issue 18
TS Traffic Installation Testing
2.2.1 Equipment
1
A terminal block may be made up which has shorting links between each
terminal. For larger cables additional terminal blocks can be cascaded.
2
Insulation Tester
2.2.2 Method
This test is to be carried out after all the cables have been run to the signal poles and
terminated in the pole cap (sometimes connected through to adjacent poles). The lamp
transformers and all ELV connections are to be left disconnected.
Cable to Pole
Armour
Core 1 Measure Insulation
Controller End
Figure 1 - Test Block connected for testing
At the controller end, each cable is to be terminated in the test block with one core per
termination and the armour in the last position (as shown in Figure 1).
Remove the first core (Figure 1) and measure the insulation at 500V between this and
all other cores, including the armouring, in the termination block. Minimum reading
should be 20M .
Remove the second core and repeat above.
Proceed until all cores have been tested.
The test is to include all cores including spare cores and cores reserved for ELV
applications.
Record the lowest reading obtained on each cable on the form in Appendix B.
667/HE/20664/000
Page
13
Issue 18
TS Traffic Installation Testing
2.3
VISUAL INSPECTION
Before connection to the mains supply a visual inspection of the installation is to be
undertaken. Visual inspections will consist of the following:
i)
All lanterns are correctly aligned and securely fastened in accordance with the
STS.
ii)
All push buttons are securely fastened and their doors tightened down. Ensure
that the correct operating voltage of the wait lamp is clearly indicated on the
label inside the push button box.
iii)
All pole caps are correctly installed and that no gaps exist to allow the ingress of
water.
iv)
Controller base seal is not punctured, and is free from gaps around cables.
v)
Ensure all earth connections are securely made off:
Main earth conductor to the mains supply.
All cable armouring is secured correctly to the castellated bar or where
applicable that all CET glands are correctly made off and secured to the
earth bar.
Controller doors have their earth straps correctly connected to the
controller case.
Castellated or earth bars are correctly bonded to the Main Earth Terminal.
2.4
vi)
Check that terminal block connections are securely made.
vii)
Check that terminal block connections are not loose, especially where more than
one conductor uses the same terminal.
viii)
Check that conductor/wire insulation has not retracted from terminal
connections. There must be no exposed conductor on new installations. The
maximum allowable length of exposed conductor is 2mm in any circumstance. It
is noted that Regulation 559.10.3.1 allows for a minimum degree of protection of
IP2X (12mm diameter), but Siemens Mobility - Traffic Solutions chooses 2mm
maximum.
CIRCUIT PROTECTIVE CONDUCTOR (CPC) TEST
It is necessary to test and verify the continuity of the CPC of each cable run to the
furthest earthed point, this may be a pushbutton or similar pole mounted item. The
results of these tests will be recorded in the Test Results section of Appendix B. The
following tests can be completed after the installation has been fully terminated, but
before any power is applied to the installation.
This test is also required for the ELV controllers. In this case, the Continuity Protective
Conductor (CPC) resistance shall not be greater than 2.2 Ohms. This impedance is
slightly higher than the CPC resistance of the armouring of a 250m long 1.0mm2 cable
(8 core), but offers a degree of protection against an accidental short-circuit from a
667/HE/20664/000
Page
14
Issue 18
TS Traffic Installation Testing
third party’s mains supply at the signal head. Any third party LV supply must be
separated from the TS ELV supply in all instances; it is recommended that the
installation is entirely ELV.
2.4.1 Provision of cable cores for test purposes
During the termination of cables at signal poles two “spare cores” are selected for the
purpose of testing and feed through poles to the furthest pole where they will be
connected to the earth terminal. Where a cable run “loops” through other poles, it is
essential to use two spare terminals at the pole top to connect through cores. These
test cores must not be connected together at any pole other than the last pole on a
cable run. At the controller end these cores will be identified as “Test Cores” and
labelled to indicate to which cable run they are connected.
2.4.2 Loop Resistance of Two “Test” Cable Cores on Each Cable Run
Using the low resistance test instrument identified in 2.1 i), zero the test leads,
measure at the controller the loop resistance of the two test cores for each cable run.
The results of these tests will be inserted in the “Core to Core Resistance” box in the
Installation Test Results form.
The resistance should be no greater than that stated in the following table, if greater,
then all pole terminations should be checked for tightness. If all pole terminations are
correct, perform further loop resistance checks at each pole, working out along the
cable run from the controller until the particular cable at fault is isolated.
Before testing, zero the meter.
1mm2 Resistance
1.5mm2 Resistance
@ 25oC (round trip)
@ 25oC (round trip)
Expected CPC
resistance (armour)
36.92
24.68
7.8
1 Km
18.46
12.34
3.9
500 metres
9.23
6.17
1.95
250 metres
4.61
3.08
0.98
125 metres
2.77
1.87
0.59
75 metres
1.85
1.25
0.39
50 metres
0.74
0.5
0.16
20 metres
0.37
0.25
0.08
10 metres
Approximate
distance to signal
TABLE 1
‘Expected CPC resistance’ is the typical value of resistance of the metal cable
sheath/armouring for 8-core 1mm2 cable. Larger cables have lower CPC values.
2.4.3 Loop Resistance of Cable Core (R1) and CPC (R2). For Poles without push buttons.
Using the low resistance test instrument identified in 2.1 i), zero the test leads,
measure the loop resistance between one cable core (R1) and the CPC (R2) for each
cable run, as measured from the cable core to a local earth connection. (Unless there
667/HE/20664/000
Page
15
Issue 18
TS Traffic Installation Testing
are exceptional circumstances the cable armouring would be used as the CPC). The
results of these tests will be inserted in the "Core to CPC Resistance" box in the
Installation Test Results form. This gives (R1 + R2).
2.4.4 Loop Resistance of Cable Core and CPC. For Poles with push buttons.
This test is to be conducted even on poles which only have ELV. Connect the CPC (R2)
at the pushbutton to one other core (Rt) in the drop cable. Then connect one of the test
cores (R1) to the same core of the drop cable. This will create a loop including the CPC
of the controller to pole cable(s), the CPC drop to the pushbutton, the other core in the
drop cable and the test core. Using the low resistance test instrument identified in 2.1
i), zero the test leads, measure the loop resistance between one cable core (R1) and
the CPC (R2) for each such cable run. (Unless there are exceptional circumstances the
cable armouring would be used as the CPC). The results of these tests will be inserted
in the "Core to CPC Resistance" box in the Installation Test Results form.
As an alternative method two cores in the drop cable may be linked at the top cap
together and with the CPC in the drop cable, and the tests performed to determine the
impedance of the CPC in the drop to the push button. The tests are the same as those
in 2.4.2 and 2.4.3. for the controller to pole, but in this instance it is pushbutton to pole.
The test of the two ‘test cores’ should be entered in the core to core column (as in
2.4.2), the test between the two test cores and CPC should be entered in the core to
CPC column (as in 2.4.3). The impedance of the CPC may then be calculated as in
2.4.5. and then added to the impedance measured for the pole to determine the overall
impedance to the pushbutton. This overall impedance should be within the limits
required.
NB On older installations and modified ones there may be insufficient spare cores to
perform the test. The client should be informed and requested to fund the installation of
additional cores.
The CPC impedance pushbutton to pole top should be shown on the test form as shown in the example
below.
example
Cable Run:
From
To
PB1
Pole 1
2.4.5 CPC Continuity Resistance
The value to be entered in the "CPC Resistance" box of the Installation Test Results is
determined by the following method:
i)
Divide the value of Core to Core resistance by 2.
Core resistance = (R1 + R1) / 2 = R1
ii)
Subtract the resulting value from the value of Core to CPC resistance.
CPC Resistance = (R1 + R2) - R1 = R2
iii)
If the measurement was to a pushbutton (2.4.4 above), then note that the drop
cable Test Core, Rt, will add resistance to the measurement and therefore Table
667/HE/20664/000
Page
16
Issue 18
TS Traffic Installation Testing
1 should be used to determine Rt by calculating the length of the drop and the
core size for subtraction from Core to CPC resistance. Note Figure 2.
R2
= (R1 + R2 + Rt) – R1 – Rt (calculated from Table 1)
= (R2 + Rt) – Rt (calculated from Table 1)
R1, R2, Rt connectivity to measure CPC value from controller to push button
Figure 2
If the alternative method in 2.4.4 has been used the exact value of the CPC in
the drop cable can be calculated and added to the Pole CPC value.
iv)
This will leave the resistance value for the CPC, R2.
The determined value can then be entered in the "CPC Resistance" box in the
Installation Test Results form.
The figure for a typical armoured multi-cored cable (8 core) should be in the region of
0.78 per 100m of cable length. If the resistance is greater than 0.78 per 100 meter
of cable length then it will be necessary to investigate the cause and remedy the
problem.
On completion of tests 2.4.2 and 2.4.3 or 2.4.4 the "Test Cores" are to be labelled and
made off. The remote ends are to be connected to earth and the controller end tied
back and insulated. These test cores may be used for testing if future earthing
problems are discovered.
2.5
BASIC POLARITY TEST (ADDITIONAL)
This test will have been carried out on all Controllers supplied as they are all required
to meet IET Wiring Regulations 17th Edition. This includes ST950, ST900, ST800 and
ST700 Controllers (Controller Factory test documentation can be supplied on request).
667/HE/20664/000
Page
17
Issue 18
TS Traffic Installation Testing
However, if the client requires this further test to be performed or is in any doubt about
the Controllers, then he may request this extra test which will be charged over and
above the normal rate for this testing.
With controllers having solid state or other lamp switch outputs and many having fuses
mounted on PCBs or within the controller assemblies, which will have been tested as
part of the controller manufacture, a polarity test of these is unnecessary and
impracticable. A basic test to check fuse carriers and switches on the main and
controller switch assemblies, (that may be rewired / altered during the controllers use /
installation), shall be performed, as follows.
Connect the phase (line) conductor to the Circuit Protective Conductor (Main Earth
Terminal), at the input to the controller. Then for each of the following at the furthest
point accessible before entering controller control modules, measure between earth
and the phase (line) conductor (this should show short circuit / low impedance).
Operate the single pole protective devices (remove fuses or operate circuit breakers),
and any switches. Check that the circuit is broken i.e goes open circuit / high
impedance. If the circuit does not break this would indicate a wiring fault / protective
device fault and should be investigated.
Check: Lamp Supply, Regulatory Sign supply, solar cell supply and auxiliary unit
supplies.
2.6
SITE INSULATION TEST
This test will be performed AFTER the completion of all signal cable terminations and
BEFORE the controller is connected to the incoming mains supply. Where a controller
has been connected to the mains supply, the Master Switch must be set to the OFF
position during this test.
2.6.1 Preparation
The controller must be isolated for this test (i.e. both LINE and NEUTRAL conductors
disconnected by switching). This is normally accomplished by switching OFF the
MASTER SWITCH. If in any doubt, then refer to the handbook for the type of controller
being tested. (N.B. The MASTER SWITCH may be in the Haldo pillar).
An Uninterruptible Power Supply (UPS) solution is available for ELV/LV LED Traffic
Controllers with loads up to 2000W. Note that if a UPS is fitted to the controller,
isolating the mains supply at the Haldo pillar will not remove power to the controller
mains input unless the UPS is switched to BYPASS.
Ensure all other switches are ON, i.e. controller switch, signals ON/OFF switches.
Ensure all phase cable cores are connected up as required for normal operation.
All phase switch/phase driver PCBs etc. are to remain fitted.
With most types of 13 Amp Socket with built in 30mA RCD, it is ideal for the RCD to be
tripped OFF before insulation testing. However this is not possible without applying
power so for initial installation it is necessary to include them in the insulation test. If
there are problems passing, it may be necessary to disconnect 30mA RCDs for the
test. Ensure that the connections are restored after the test. After mains power is
applied to the controller, the RCDs can be tripped off instead of being disconnected.
Note that it is important that any RCDs which have been insulation tested while ‘ON’
should subsequently be tested and pass the RCD tests of section 2.9 below.
667/HE/20664/000
Page
18
Issue 18
TS Traffic Installation Testing
Surge Protection Devices such as the TS DIN rail mounted 516/4/00136/000 contain
275VAC varistors. Disconnect these before the Insulation Test.
The Gemini 2 unit also contains varistors, and should be disconnected before the
Insulation Test.
Varistors will not be damaged by the Insulation Test, but will affect the result.
Ensure that all varistor/Gemini2 modules are correctly re-connected after the test.
2.6.2 Test
The Insulation test instrument must be set to 500 Volts. This will avoid false low
impedance readings that may be obtained using higher test voltages, which trigger the
Surge Protection Devices (SPD) fitted to some modern equipment (including TS LED
Signals).
BS7987 / HD638 section 8.6 (the European standard for Traffic Signal systems) and
IET regulations allow for testing at 500 Volts defined in BS 7671 Table 61 IET Wiring
Regulations 17th Edition, with a minimum insulation resistance of 1M . It should be
noted that Insulation resistance values are usually much higher than this, and will
typically exceed 10M .
Connect the Megger test instrument between the neutral (black) and line (red)
(connected together), and earth (green/yellow) on the Panel where all site cables are
terminated. Test insulation impedance. It must be greater than 1M . (Note that this test
relies on line and neutral being connected together).
During this test the insulation to earth of all cable cores, aspect cables, and aspect
transformers are checked and the failure of any one item may be indicated by a lower
than expected reading.
If this test fails, disconnect signal cables and re-test.
If the test now passes, the fault is in the cables; test the individual cores until the fault
is traced.
If test still fails, the fault is in the controller. Disconnect individual parts of the controller
(re-testing each time) until the fault is traced. Controller parts that could give rise to low
reading are:
over voltage protection (see section 2.6.1 above)
Gemini 2 unit (see section 2.6.1 above)
lamp switch / lamp driver PCBs
filters
logic transformer
modular power supplies
maintenance sockets with integral RCD (see section 2.6.1 above)
and any other item which is connected to earth and to which mains voltage is
also connected).
In an ELV controller, the Mains (LV) circuits in the Controller should be subject to the
Insulation Resistance test. In an ELV controller, Earth is connected to the common
connection of all ELV loads, so the Insulation Resistance test on the Mains circuits will
test that the street wiring has appropriate Insulation Resistance to Mains. Core to Core
testing described in 2.2.2 should have been completed prior to connection of signal
heads. Where a customer requests cable core insulation tests as part of a periodic
inspection on ELV signal circuits, to check for any degradation on a cable, then site
667/HE/20664/000
Page
19
Issue 18
TS Traffic Installation Testing
spare cores in street wiring should be used, however it should be checked that they are
not connected together or to earth at any point these can then be subjected to
Insulation Resistance Testing to prove that the street wiring has not degraded.
Fill in the inspection certificate as far as possible. The installation can now be
connected to the mains supply and powered up ready for the commissioning tests to be
completed.
2.7
POLARITY TEST
The object of this test is to check that the controller is connected to Line and Neutral in
the correct sense and there is isolation between all the phase conductors and the
control equipment.
The diagrams below show a TN-S supply connected to a Controller, and a TT supply
connected to a Controller.
TN-S Supply
L
Controller
L
N
N
E
E
300mA
RCD
Load
Feeder Pillar
Local Earth connections
through Controller stool,
poles etc.
DNO Supply
TT Supply
Controller
Feeder Pillar
L
L
N
N
300mA
RCD
Load
E
DNO Supply
Earth electrode
Local Earth connections
through Controller stool,
poles etc.
For a TN-S supply or TT supply, the following simple polarity and isolation tests are
suitable. Check that the polarity of the line phase conductor on the incoming / supply
side of the Controller master switch is in the correct sense, i.e. the voltage measured
from Line to Earth is approximately 230V AC and the voltage measured from Neutral to
Earth is less than 10V AC. Isolate the controller using the master switch (if not already
667/HE/20664/000
Page
20
Issue 18
TS Traffic Installation Testing
so) and repeat the measurements on the out going / controller side, there should be no
voltage measured.
NOTE
A TN-S supply or TT supply can be successfully polarity tested
without removal of the Earth connection. This does not apply to a
TN-C-S supply!
The diagram below shows a TN-C-S supply connected to a Controller.
TN-C-S Supply
L
Controller
L
N
N
300mA
RCD
Load
E
Feeder Pillar
Local Earth connections
through Controller stool,
poles etc.
DNO Supply
If the TN-C-S supply has the Line and Neutral connections reversed, the local Earth is
connected to supply Line, instead of supply Neutral, as shown below.
This situation could go un-noticed, because all local Earth connections are made to
supply Line. One evidence of wrong polarity is that the ground around locally earthed
metalwork dries much more quickly than other ground after rain.
NOTE
667/HE/20664/000
A TN-C-S supply CANNOT be polarity tested without removal
of the Earth connection.
Page
21
Issue 18
TS Traffic Installation Testing
ELI testing must not be carried out on a TN-C-S installation where
there is reason to suspect wrong mains polarity.
Supply polarity can only be tested by switching off the junction, so that the incoming
Line and Neutral can be measured with respect to an independent known Earth (such
as the CET bars with the incoming Earth connection removed). See the diagram
below. This is a hazardous procedure, as the Local Earth connection is now connected
to true Earth through the ground, and the earth wire from the Feeder Pillar is connected
to the supply Line, if the supply polarity is reversed. This test must NOT be carried out
by Siemens employees, due to the hazards involved.
However at the beginning of a new installation, while the fuse in the feeder pillar is still
unconnected and the controller earth has not yet been connected to the Feeder Pillar
earth, it is advisable to check for supply reversal by carefully measuring the voltage of
the earth wire from the Feeder Pillar with respect to local earth at the controller stool
(must be less than 10V AC).
Be aware that if there is reversed supply polarity, the earth from the
Feeder Pillar is live and dangerous at this stage! Avoid touching the earth
wires or Feeder Pillar enclosure during this test. This test is particularly
advisable when installing a new controller on an old site with existing Feeder Pillar.
In the unlikely event that there is a supply polarity reversal between the Feeder Pillar
and Controller, this is Siemens responsibility, and needs to be corrected! Note that
Controller Supply Polarity is tested in the Factory, and only needs to be re-considered
when any changes have been carried out, such as adding extra switchgear to the
Master Switch Assembly.
WARNING
TN-C-S supply polarity on an installed controller must
only be tested by the DNO, when there is good reason
to suspect wrong polarity. Diagram for information only,
to highlight the electrical hazards.
BS7671:2008 now includes Amendment No. 1:2011, which shows a Supply Polarity
check during Periodic Inspection. This test requires the junction to be switched off, so
that the incoming Line and Neutral can be measured with respect to an independent
known Earth.
667/HE/20664/000
Page
22
Issue 18
TS Traffic Installation Testing
The traffic accident risk is increased when a junction is switched off. It is
recommended that a Supply Polarity check on an installed controller is only performed
by the DNO, when there is reason to suspect wrong polarity and a Risk Assessment
indicates that the wrong supply polarity risks exceed the traffic accident risks.
The Electrical Installation Condition Certificate includes the following in the Remarks
box, “Risk assessment carried out. No known electrical work done to affect Supply
Polarity, so polarity not checked. (Cross out, if inapplicable).” Risk Assessment
includes, but is not limited to, inspection of the Feeder Pillar, base seal, incoming
supply tails and Log Book. If in doubt, refer to your Supervisor, or the DNO supply
authority.
2.8
EARTH LOOP IMPEDANCE TESTS (Z s)
2.8.1 General Information
The ELV system only requires an Earth Loop Impedance test to be done on the Mains
electrical supply to the controller cabinet, and not on the supply from the controller,
which is less than 50VAC nominal. Consideration of ELI offers a degree of protection
against an accidental short-circuit from a third party’s mains supply. Any third party LV
supply must be separated from the TS ELV supply in all instances; it is recommended
that the installation is entirely ELV.
Ensure any UPS is switched to BYPASS before performing ELI tests on the controller.
Earth Loop Impedance tests are carried out at any points in the system where mains
and exposed metal work are present. The fault path within the installation comprises
the live conductors (R1), control equipment (either a traffic or pedestrian controller) and
the CPC (R2). The fault path external to the installation (Ze) contains the supply
authority's transformer windings, the line conductor and CPC of the supply authority's
distribution network, or the earth electrode. The Earth Loop Impedance test carried out
at the end of each cable run in an LV traffic signal installation will include both
elements described above.
Note that:
Zs = Ze + (R1 + R2)
The Earth Loop Impedance test results are required to ensure that in the event of an
earth fault (or a short circuit fault) the protection devices e.g. fuses to the appropriate
circuit will disconnect within the time limit as specified in BS7671 (IET Wiring
Regulations).
For fixed equipment i.e. permanently wired traffic controllers, the specified
disconnection time for a TN system as laid down by BS 7671 IET regulations 17th
Edition is 5 seconds and for equipment connected via sockets the specified
disconnection time is 0.4 seconds.
Table 2 on page 23 indicates the maximum permissible Earth Loop Impedance values
for the various fuse and circuit breaker types in use for traffic signal installations with a
5 second disconnection time (current controller types).
Note: - There may also be other supplies associated with certain poles e.g. regulatory
sign supply, Solar Cell supply. These are generally of a lower value than the lamp
supply fuses and would therefore not affect the max value expected, however this
should always be checked, if a direct comparison with other fuses noted in Table 2 is
667/HE/20664/000
Page
23
Issue 18
TS Traffic Installation Testing
not possible, or in doubt. Then the fuse and Earth Loop Impedance tables in the IET
Regulations 17th edition section 411.4.8 Table 41.4 for 5 second disconnection, should
be consulted, remembering that temperature compensation needs to be applied using
calculation or rule of thumb described in Appendix 14 of the IET Wiring Regulations
17th Edition as follows: Rule of Thumb Zs (m)
0.8 x Uo / Ia
Where Zs (m) is the measured impedance of the earth fault current loop up to
the most distant point of the relevant circuit from the origin of the installation.
Uo is the nominal a.c. rms voltage to Earth.
Ia is the current causing the automatic operation of the protective device within
the time stated in the IET regulations.
When installing third party equipment it will be necessary to refer to the technical
handbook to determine the fuse type and value protecting the relevant circuits.
These figures should be given in the Particulars of the Installation portion of the
completion form.
The LT5 tester currently recommended for carrying out Earth Loop Impedance tests is
only suitable for supply voltages in the range 200V to 260V. It is not possible to test
circuits when supplied by a lower voltage than 200V i.e. dimmed lamp supply.
The Earth Loop Impedance test measures the Earth Loop Impedance by connecting
line to earth via a low resistance, causing a simulated fault current of approx. 25 Amps
to flow for a period of approximately 10 - 20 milliseconds around the loop.
SAFETY NOTE. It is therefore vital to ensure that NOBODY is in contact
with the pole or cabinet during the Earth Loop Impedance test.
CAUTION
ELI testing must not be carried out on a TN-C-S installation
where there is reason to suspect wrong mains polarity.
If satisfactory Earth Loop Impedance results cannot be obtained, then consideration
should be given to fitting a 300mA RCD to the controller supply.
2.8.2 Preparation
Ensure all phase cable cores are connected up as required for normal operation.
The controller should be switched on and operational (signals illuminated). Ensure
signal heads are covered at this time to prevent spurious signals to road users.
Every pole, cabinet, wait indicator (230V) and controller door must be tested and
recorded on the form in Appendix B. Within the cabinet at least the following shall
be tested - Main Earth Terminal, Distribution panel, Castellated bar or CET bar as
fitted, Front door on unpainted area around door catch, Rear door (if applicable)
unpainted area or earth stud, Front panel earth stud, Maintenance socket Earth pin.
The values measured within the controller cabinet (see also Appendix B ‘mains live’
list of tests) should be below the values for the master fuse. The values measured
on phase outputs at poles should be below those noted under signal fuses (ELI
667/HE/20664/000
Page
24
Issue 18
TS Traffic Installation Testing
values for the controller fuse are provided for completeness but are not used).
Access to mains live within the controller cabinet requires removal of the fuse cover
and connection into live on the output of the master switch – take care to avoid
electric shock. Re-fit the fuse cover after the tests and fully secure it in place.
If the ELI measurement within the cabinet exceeds the values shown in Table 2 for
the appropriate specification of fuse, do not proceed with further testing and report
the supply as out of specification to the customer concerned. If the supply authority
cannot improve the characteristics of the supply to improve Ze (e.g. lower
impedance earth return), then a permissible solution is to fit a 300mA RCD to
protect the whole installation. For measurements at poles, a failure may indicate
the need for larger cable size, use of additional parallel cores, or improved earth
connection from cable armour to the pole.
667/HE/20664/000
Page
25
Issue 18
TS Traffic Installation Testing
Table 2 Fusing and ELI for Current Controllers
Controller fuses and allowable Earth Fault Loop Impedance Zs @ 20°C
compensated for 70°C operation by Rule of Thumb Method from IET Regs
Master fuse
Controller fuse
Signal fuse
230V
160V
140V
120V
ST900/ Part number
ST950 Fuse standard
LV
Amps
Max earth loop imp.
518/4/90637/003
BS1361/BS88
45
0.73
518/4/90638/005
BS1361/BS88
30 or 32
1.28
240V
167.2V 146.3V
125.4V
518/4/90301/013
EN 60127 – 2/1
10
5.44
3.78
3.31
2.83
ST900/ Part number
ST950 Fuse standard
LV LED Amps
Max earth loop imp.
518/4/97092/020
IEC60269/BS88
20
2.24
518/4/90352/005
BS88/IEC60269
16
3.12
518/4/90301/013
EN 60127 – 2/1
10
5.44
3.78
3.31
2.83
ST900/ Part number
ST950 Fuse standard
ELV Amps
Max earth loop imp.
518/4/90637/001
BS1361/BS88
30 or 32
1.28
516/4/02061/000
MCB type D
20
No PCB fuses on LSLS card
HPU F4 30A 518/4/97079/001
6A type C MCB for AUX
ELV – ELI is calculated
ST900/ Part number
ST950 Fuse standard
ELV low Amps
inrush
Max earth loop imp.
518/4/90637/007
BS88/IEC60269
16
3.12
516/4/02061/000
MCB type D
6
No PCB fuses on LSLS card
HPU F4 30A 518/4/97079/001
6A type C MCB for AUX
ELV – ELI is calculated
ST900/ Part number
ST950 Fuse standard
ELV Amps
40A
Max earth loop imp.
518/4/90637/001
BS1361/BS88
30 or 32
1.28
516/4/02061/001
MCB type D
32
No PCB fuses on LSLS card
HPU F4 30A 518/4/97079/001
6A type C MCB for AUX
ELV – ELI is calculated
ST750 Part number
LV
Fuse standard
Amps
Max earth loop imp.
516/4/97053/002
BS1361/BS88
20
2.13
518/4/97056/012
IEC60068/GAM T1
16
3.12
518/4/90301/013
EN 60127 – 2/1
10
5.44
3.78
3.31
2.83
ST750 Part number
ELV Fuse standard
Amps
Max earth loop imp.
516/4/97053/002
BS1361/BS88
20
2.13
ST800 Part number
Fuse standard
Amps
Max earth loop imp.
518/4/90637/003
BS1361/BS88
45
0.73
518/4/97052/020
UL248
10
ELV – ELI is calculated
518/4/90638/005
BS1361/BS88
30 or 32
1.28
518/4/97056/010
IEC60068/GAM T1
10
5.44
3.78
3.31
2.83
NB The values for dimmed voltages are based on the ratio of the open circuit supply
voltage (Uo) used for calculation of ELI in BS7671 i.e. 230V, and the open circuit value
(Uoc) for the dimming supply i.e. dim supply + 4.5% e.g. 160V Uo is 167.2V Uoc.
Pole and push-button ELI tests on LV controllers should use the Signal fuse values.
The test is performed at 230V (test in bright) to obtain the ELI value. If the controller is
able to run in dim, the maximum allowed ELI value must be taken from the dimmed
voltage which applies to that installation. E.g. bright-only ST950LV is 5.44 max, but if
dimming to 160V the maximum ELI value is reduced to 3.78 .
667/HE/20664/000
Page
26
Issue 18
TS Traffic Installation Testing
BS1361 fuses may still be found, so values for these are taken from the 2008 version
of the Regs, and multiplied by 0.8 (thermal) and then 0.95 (voltage tolerance).
The ELI value given for 45A and 20A fuses applies to BS1361 and BS88 fuses, and the
ELI value for ’30 or 32’ fuses applies to BS1361 30A fuses or BS88 32A fuses. For a
45A fuse, the value for BS88 is higher than for the older BS1361 so on a borderline
case, it is permissible to check if the fuse is the BS88 type and if so to use the higher
value of 0.8 . In this case a note should be made that only BS88 fuses are to be used.
An auxiliary circuit supplied from a 6A Type C MCB should have an ELI below 2.91 .
Note as this is the installation section, the above Table 2 only contains those
controllers that may still currently be being installed, for older controllers please see
section 4.2 (page 41).
2.8.3 Fuse Replacement
Following any Earth Loop Impedance tests all fuses (with the exception of the supply
authority's fuse) which have been placed under stress are to be changed.
A fuse with a current rating of less than 10A will be considered to have been placed
under stress.
2.8.4 Measuring Earth Loop Impedance at The Origin, Prospective Short Circuit Current and
Prospective Fault Current.
A TN-C-S supply should have the following characteristics quoted by the supply
authority. Where the prospective fault current is available from the supply authority, it
should be recorded in the appropriate area on the installation completion form, if
unavailable, it may be left blank. However the following tests must always be
conducted and the resulting maximum value entered on to the forms as measured
value.
Supply Volts:
230 V
Prospective Fault Current:
16KA
If the maximum prospective fault current of 16KA is exceeded then the equipment
should not be connected to this supply without reference to Engineering.
The Origin is the point where the Electricity Company equipment is terminated and the
cables from this point belong to the customer. However for safe and easy access to test
points, the test should be performed at the terminals on the incoming / supply side of
the Controller master switch. This will also allow the inclusion of any cable between the
electricity board cut-out and the controller switch in the calculations.
Ensure any UPS is switched to BYPASS before performing ELI tests.
INITIAL INSTALLATION TESTING If this is a test of the initial installation, then in
order to avoid multiple paths to earth (i.e. through controller and poles installed in the
ground), disconnect the earth point provided by the supplier from the controller, and
then test the supplier’s earth point.
For this test, ensure the Controller master switch is ‘OFF’ so that the
temporarily unearthed controller is not powered.
667/HE/20664/000
Page
27
Issue 18
TS Traffic Installation Testing
Warning: proceed with caution – inspect the incoming supply wiring
before removing the earth, and ensure the period of time when earth
is disconnected is minimised i.e. perform the test and reapply the
earth as soon as possible.
For subsequent testing during maintenance and/or periodic inspection
and test, the main earth is not to be disconnected to reduce the
likelihood of damage or poor re-connection.
Connect the LT5 2-core adapter lead to the earthing point provided by the supplier and
the main line feed. Measure and record (under Particulars of the Installation) the Earth
Loop Impedance at the origin (Ze).
The Prospective Fault current at the origin can be calculated from this reading using
the following formula:
Prospective fault current
=
___230V___
ZL-E at origin (Ze)
If this value exceeds 16000 amps refer to Engineering. Make a note of the value
before continuing to the next test.
Repeat the above test between the line and neutral conductors of the incoming supply,
(ZL-N). The Prospective short circuit current at the origin can be calculated from this
reading using the following formula:
Prospective short circuit current = ___230V___
ZL-N at origin (Ze)
If this value exceeds 16000 amps refer to Engineering.
Record the highest fault current either Line to Neutral OR Line to Earth on the record
sheets against ‘Max Prospective Fault Current’.
If the main earth has been disconnected from the
controller during ‘Initial Installation test’, ENSURE
IT IS NOW RE-CONNECTED.
2.8.5 Measuring Earth Loop Impedance at Poles and Push buttons in LV installations
At all poles and wait boxes the Earth Loop Impedance is measured using any phase
conductor feed to the pole, connecting the LT5 earthing test lead to the appropriate live
feed and to the metal of the pole itself (to include pole earthing in the test).
Measure and record the Earth Loop Impedance at each point of a cable run. Ensure
that the value is less than the maximum permissible value detailed in Table 2 on page
23 under Signal fuses.
Note: - There may also be other supplies associated with certain poles e.g. regulatory
sign supply, Solar Cell supply. These are generally of a lower value than the lamp
supply fuses and would therefore not affect the max value expected, however this
667/HE/20664/000
Page
28
Issue 18
TS Traffic Installation Testing
should always be checked, if a direct comparison with other fuses noted in Table 2 is
not possible, or in doubt. Then the fuse and Earth Loop Impedance tables in the IET
Regulations, should be consulted, remembering that temperature compensation needs
to be applied using calculation or rule of thumb described in 2.8.1.
Where a mains supplied wait indicator is fitted, the Earth Loop Impedance of the push
button box is measured by connecting the LT5 test cable between the centre pin of the
lamp holder and the case of the push button. If the push button box is of the type fitted
with a separate terminal block then it is preferable to take the live supply from this
terminal.
Note: It is not practicable to test Poles fitted only with equipment having less than 50V
e.g. 24V detector poles or FELV wait indicators, as a live 230V supply is not available
for the Earth Loop Impedance tester. They should however have been CPC continuity
tested and the ELI (Zs) value can now be calculated by adding the measured CPC loop
value to the measured Ze at origin for the point supplying the ELV pole e.g. this may be
the controller cabinet or a LV pole see the following section.
2.8.6 Calculating the ELI value for ELV only poles
As noted in 2.8.5 above without an LV supply to a pole (i.e. on an ELV only pole), the
measurement of the ELI with an ELI meter is not practicable. However the value can be
calculated from the CPC values measured in 2.4.5 earlier in the test procedures. Take
the value noted in the ‘Loop Resistance Core to CPC (2.4.3 or 2.4.4)’ column of the
CPC resistance test results, for the ELV pole(s), add to this the measured ELI value
for the point from which the ELV pole is supplied (NB this may be the controller cabinet
or an LV pole). Put the resultant value in the ELI column for the ELV pole and mark it
with an * to indicate that it is a calculated value.
On ELV controllers the CPC to signal poles etc should be measured and confirmed to
be less than 2.2 in accordance with section 2.4. The calculated ELI value for pole
connections in ELV controller installations should also be kept below the 230V value
for a 10A fuse, i.e. 5.44 . The calculated ELI is the measured mains origin ELI Ze,
plus the measured CPC of the armoured cable to the pole, plus the measured
resistance of an ELV phase core from controller to pole.
2.8.7 Measuring Earth Loop Impedance within the Controller Cabinet
Within the cabinet at least the following shall be tested - Main Earth Terminal,
Distribution panel, Castellated bar or CET bar as fitted, Front door unpainted metal,
667/HE/20664/000
Page
29
Issue 18
TS Traffic Installation Testing
Rear door unpainted metal/earth stud, Front panel earth stud, Maintenance socket
Earth pin.
Ensure any UPS is switched to BYPASS before performing ELI tests.
To test, Connect the Red probe to the line supply on the output of the master switch
and the earth test probe of the tester (Black probe) to each of the test points.
Note: - the values measured within the controller cabinet should be below those
values for the master fuse. The values measured at poles should be below
those noted under Signal fuses.
2.8.8 Controller RCD Fitted To Incoming Power
In some areas it will be found that an RCD has been specified to protect the whole
installation. A 300mA RCD should not be affected by the LT5 test. It may be necessary
for the RCD to be bypassed for the purpose of completing the Earth Loop Impedance
tests, and reconnected before commissioning of the site.
2.8.9 Maximum Allowable Earth Loop Impedance With in-line RCD
The maximum allowable Earth Loop Impedance Zs of an installation following an in-line
RCD is calculated using the following formula derived from IET Wiring regulations 17th
Edition 415.2.2:
Zs =
50 X 1000
I (mA)
Where I (mA) is the operating current in milliamps of the protective device – for RCDs
I n.
Note: For a 300 mA RCD, it is recommended that Zs does not exceed 100 ; and for a
30 mA RCD, it is recommended not to exceed 1000 . Note, however, that the
ELI should be as low as possible. Values over 200 should be investigated and
reasons confirmed..
Note: 30mA RCD is not recommended on a junction as nuisance tripping
can occur.
2.9
RCD TEST
This test is performed with the RCD test meter see 2.1 Test Equipment. The test
measures the actual disconnection time of the RCD. The following tests are required to
be completed in both polarities. Some meters automatically change polarity for
consecutive tests e.g. Seaward RC750, others will require a manual selection change.
2.9.1 30mA Trip Current RCD Protecting Maintenance Socket
Nuisance trip test: Connect the RCD tester into the maintenance socket. Set the test
trip current to 15mA (30mA / 2), select positive half cycle, press test button: The RCD
should not trip. Reset the RCD, select negative half cycle and repeat test. (I n/2 test)
667/HE/20664/000
Page
30
Issue 18
TS Traffic Installation Testing
Connect the RCD tester into the maintenance socket. Set the test trip current to 30mA,
press test button: The maximum allowable trip time is 0.2 seconds. Reset the RCD,
select negative half cycle and repeat test. (I n test)
Reset the RCD. Set the trip current to 150mA and re-test: The maximum allowable trip
time is 0.04 seconds. Reset the RCD, select negative half cycle and repeat test. (5I n
test)
If any test other than the first 15mA test fails, replace the RCD. If only the nuisance trip
test fails, consult the client, if they use the socket to power permanently installed
equipment, they may wish it to be replaced.
Note IET regulations 17th Edition section 415.1 Additional Protection (RCD’s).
2.9.2 300 mA RCD Protecting Whole Installation (If fitted)
WARNING: Tripping the RCD will switch off the signals. Ensure that the
signals are switched off or covered prior to carrying out this test to
avoid confusion to motorists.
Trip the 300mA RCD using the test button. (The whole installation will switch off).
Switch off the master switch and connect to the line and neutral terminals using an
adapter lead. (Either use probes or connect into the line and neutral termination
points). Connect the earth to the main earth terminal.
Nuisance trip test: Connect the RCD tester into the maintenance socket. Set the test
trip current to 150mA (300mA / 2), select positive half cycle, press test button: The
RCD should not trip. Select negative half cycle and repeat test. The RCD should not
trip.
Reset the RCD. Set the trip test current to 300mA and perform the test: Maximum
allowable trip time is 0.2 seconds.
If test fails, replace RCD.
2.10
DETECTOR LOOP TEST
For a new installation, the loops should be tested to ensure that the recommended
limits in this section are achieved. Ensure the detector cards are disconnected for the
test, and replaced afterwards.
2.10.1 Tests
Using the Multimeter set to read continuity, measure at the controller the detector loops
and feeder cable continuity resistance. Record the reading in the detector test results
section of the completion certificate. The reading should be less than 8 .
Using the insulation tester measure the loop insulation resistance to earth and record
the reading in the detector test results section of the completion certificate. The reading
should be greater than 10M .
667/HE/20664/000
Page
31
Issue 18
TS Traffic Installation Testing
The inductance of each detector loop and feeder will be measured with the inductance
meter. This test will be made at the controller after the joint has been made. The results
will be recorded in the detector test results section of the completion certificate. The
minimum value to be 30 H, and the maximum value 500 H.
667/HE/20664/000
Page
32
Issue 18
TS Traffic Installation Testing
2.11
Additional Insulation Tests
In some cases the customer may require additional tests of cable sheath insulation. If
additional tests are required they must be performed and recorded (use additional
record sheets if required by the customer, appended to the appropriate Forms in the
Appendix of this document).
Example 1: From Series 1400 Highway Works: an insulation resistance test of 1000V
direct current instead of 500V, applied and maintained for not less than one minute
between the continuous cable armouring or earth conductor and the general mass of
earth - the measured insulation resistance shall not fall below 1.0 M ohm for the full
duration of the test. If this test is required, it shall be carried out after the cable has
been laid and the trench backfilled, but before jointing has taken place.
Example 2: Highways Agency (MCH1540F) detector loop additional tests to ensure no
water ingress: With the two conductors of a loop tail, or complete circuit (comprising a
loop and feeder) connected together, the insulation resistance between the cable
conductors and a good earth point shall be >100 M Ohms measured at 500Vd.c. Any
failures must be investigated and rectified.
2.12
NEUTRAL CONDUCTOR VOLTAGE DROP TEST
This test only applies to non LED signals. The test relies on a lamp transformer in the
signal head, so that the un-driven green ‘sees’ the signal head Neutral through the
lamp transformer.
The following test should be carried out on each phase green feed, using a digital
Multimeter or voltmeter set to measure 250V AC (RMS) or greater.
Select a phase and wait until its green has just terminated. Measure the voltage
between the controller neutral and the green feed, the voltage should be no greater
than 4V (RMS) throughout the controllers cycle, except when the phase next goes to
green. If the voltage is over 4V, refer to section 3.9.
2.13
GUIDANCE FOR GENERATORS
If a generator is connected to a traffic controller (as a temporary measure while mains
power to the junction is unavailable), the requirements for a fixed installation of up to
10kW apply. A 300mA RCD must be present between the generator and the controller,
with the neutral of the generator output connected to earth on the generator side of the
RCD. Ensure the generator frame is also reliably connected to earth. If it is not certain
at the time of connecting the generator that there is a known good earth connection
supplied via the DNO supply wiring, a local earth electrode must be utilised which has
a resistance to earth of under 167 .
The relevant official publications contain detailed requirements, and take preference
over the guidelines summarised here. For latest information refer to BS 7430 “Code of
practice for protective earthing of electrical installations” (e.g. section 7), and IET
667/HE/20664/000
Page
33
Issue 18
TS Traffic Installation Testing
document “Guidance Note 3: Inspection and Testing” (e.g. section 2.7.12 which
describes how to test a low-impedance earth electrode).
2.14
COMMISSIONING
The standard commissioning procedure should now be followed, as specified for the
particular controller. See the handbooks referenced in section 1.3.
If necessary, follow the UPS power-up sequence as defined in the UPS Handbook.
Complete the Traffic Signal Installation Completion Certificate including the form
Electrical Installation Certificate which should be completed with the client / junction
design engineer completing the first part, and the second half being completed by a TS
Engineer having verified junction cabling is as required in Junction Cabling Design
Guide (see section 1.3).
2.15
VERIFICATION OF ELI RESULTS
As a final verification of ELI results check that those for poles are below the minimum
allowed values for the appropriate signal fuse, and that those for elements within the
controller cabinet, are below the minimum allowed values for the appropriate master
fuse (see Table 2).
2.16
COMPLETION OF CERTIFICATES
The certificates in Appendix B must be completed. Please note the page which starts
with “Comments on existing installation” contains a section for a signatory for “Design”.
Certain customers who have not performed their own design verification may require
this section to be completed by a TS engineer. In this case the installation should be
checked
against
the
generic
design
document
667/DS/20664/000
or
667/DS/20664/048 as applicable.
If the customer requires their own forms to be filled in, complete the customers forms in
addition to those in Appendix B.
Also complete the checklist for new installations (schedule of inspections) at the end of
Appendix C (which is shared with Periodic Inspections).
667/HE/20664/000
Page
34
Issue 18
TS Traffic Installation Testing
3.
TESTING TO CLEAR PROBLEMS
SAFETY
Before performing any electrical tests requiring junction
isolation (signals switched OFF) the permission of the
relevant authorities must have been given. Signal heads
must be covered or "SIGNALS UNDER MAINTENANCE"
signs placed on ALL approaches.
If the signals have to be switched off for any tests, refer to Appendix E for the
suggested method.
3.1
PURPOSE
Define the methods for Electrical tests required either during maintenance, or, if
problems are found, during installation or maintenance.
These tests should only be carried out when a specific test is requested in the
Maintenance Handbook.
3.2
TEST EQUIPMENT
General: Test equipment and their leads must conform to the safety requirements as laid
down in BS EN 61557 (Electrical safety in LV systems) and BS EN 61010
(Safety requirements for electrical equipment in measurement and control).
i) A Low resistance ohm meter, or the continuity range of an insulation and
continuity tester (see iii below). An instrument to BS EN 61557-4 will meet the
requirements expressed in BS7671.
ii) Digital Multimeter capable of reading 250V or greater,
current to (10A) and continuity to 2 decimal places.
iii) Insulation Tester: Megger BM222 or similar.
iv) Earth Loop Impedance Tester. Megger LT5 or similar
v) RCD Tester capable of testing both positive and negative half cycles as
required in IET Regs 17th Edition. (e.g. Megger CBT3, Robin KMP 5404,
ISO TECH IRT 1900, Metrohm 16R, Seaward RC750).
vi) A test lamp certified to meet the requirements of the HSE, Guidance note
GS38 "Electrical test equipment for use by electricians". (This may be used in
place of a multimeter to check polarity).
Note that all test equipment must be within its calibration period.
667/HE/20664/000
Page
35
Issue 18
TS Traffic Installation Testing
3.3
TOTAL SITE/JUNCTION INSULATION TEST
3.3.1 Preparation
The controller must be isolated for this test (i.e. both LINE and NEUTRAL conductors
disconnected by switching). This is normally accomplished by switching OFF the
MASTER SWITCH. If in any doubt, then refer to the handbook for the type of controller
being tested. (N.B. The MASTER SWITCH may be in the Haldo pillar).
Note that if a UPS is fitted to the controller, isolating the mains supply at the Haldo
pillar will not remove power to the controller mains input unless the UPS is switched to
BYPASS.
Ensure all other switches are ON, i.e. controller switch, signals ON/OFF switches.
Ensure all phase cable cores are connected up as required for normal operation.
All phase switch/phase driver PCBs etc. are to remain fitted.
With most types of 13 Amp Socket with built in 30mA RCD, the RCD should be tripped
before insulation testing to avoid exceeding manufacturer’s specifications. This needs
to done while power is still applied to the controller (e.g. immediately before isolating
the power at the Master Switch).
ENSURE ALL 30mA RCD DEVICES ARE TRIPPED BEFORE TESTING.
PRESS TEST BUTTON (T) WHILST POWER IS APPLIED TO SOCKET.
RCD SHOULD TRIP AND THE APPROPRIATE INDICATOR SHOULD
INDICATE THIS ON THE SOCKET.
Surge Protection Devices such as the TS DIN rail mounted 516/4/00136/000 contain
275VAC varistors. Disconnect these before the Insulation Test.
The Gemini 2 unit also contains varistors, and should be disconnected before the
Insulation Test.
3.3.2 Test
The Insulation test instrument must be set to 500 Volts. This will avoid false low
impedance readings that may be obtained using higher test voltages, which trigger the
Surge Protection Devices fitted to some modern equipment (including TS LED Signals).
BS7987 / HD638 section 8.6 (the European standard for Traffic Signal systems) and
IET regulations allow for testing at 500 Volts.
Connect the Megger test instrument between the neutral (black) and earth
(green/yellow) on the Panel where all site cables are terminated. Test insulation
impedance. It must be greater than 1M . (Note that this test relies on low impedance
between line and neutral within the controller to effectively link line to neutral).
During this test the insulation to earth of all cable cores, aspect cables, and aspect
transformers are checked and the failure of any one item may be indicated by a lower
than expected reading.
If this test fails, disconnect signal cables and re-test.
If the test now passes, the fault is in the cables; test the individual cores until the fault
is traced.
667/HE/20664/000
Page
36
Issue 18
TS Traffic Installation Testing
If test still fails, the fault is in the controller. Disconnect individual parts of the controller
(re-testing each time) until the fault is traced. Controller parts that could give rise to low
reading are:
over voltage protection (see section 3.3.1 above)
lamp switch / lamp driver PCBs
filters
logic transformer
modular power supplies
and any other item which is connected to earth and to which mains voltage is
also connected.
Ensure any disconnected parts are reconnected, and any tripped RCDs are reset, after
the insulation test before continuing.
3.4
EARTH LOOP IMPEDANCE TEST (Z s)
3.4.1 Preparation
Ensure all phase cable cores are connected up as required for normal operation.
The controller should be switched on and operational (signals illuminated) unless
stated in the following subsections.
SAFETY
During test ensure that NOBODY is in contact with the pole or cabinet
under test. Poles should be tested in sequence, working from the
controller outward.
3.4.2 Tests
Using an LT5 tester:
Connect the Red probe to the line input and the earth test probe of the tester (Black
probe) to each of the test points listed below in turn. Note that not all points are
applicable to all types of controller. For in-cabinet tests, connect to the live line on the
output of the master switch by removing the fuse cover. Replace the fuse cover after
the tests and fully secure.
Test Points:
Main Earth Terminal
Distribution panel
Castellated bar or CET bar as fitted
Front door unpainted metal
Rear door unpainted metal/earth stud
Front panel earth stud
Maintenance socket Earth pin
667/HE/20664/000
Page
37
Issue 18
TS Traffic Installation Testing
(Normally the earth fault loop impedance of the socket earth pin would only be that
necessary to trip the RCD. However any item earthed by this socket may come into
contact with a mains supply in the controller which is not disconnected by the RCD.)
3.4.3 Maximum Allowable Impedance (fuse protected)
The maximum allowable Earth Loop Impedance (Zs) for fixed circuits (5 seconds
disconnect) for controllers protected by fusing only is shown in Table 2 in section 2.8.2
for current controllers and Table 3 in section 4.2 for legacy controllers.
3.4.4 Maximum Allowable Impedance (RCD protected)
The maximum allowable Earth Loop Impedance of an electrical installation following an
in-line RCD is calculated by using the formula:
Zs = 50 X 1000
I(mA)
Where I (mA) is the operating current in milliamps of the protective device – for RCDs
I n.
Note: For a 300 mA RCD it is recommended that Zs does not exceed 100 , and for a
30 mA RCD it is recommended not to exceed 1000 . Note, however, that the
ELI should be as low as possible. Values over 200 should be investigated and
reasons confirmed..
3.4.5 Fuse Replacement
Following an Earth Loop Impedance test, all fuses (with the exception of the Electricity
Supplier's fuse in the cut-out) which have been placed under stress are to be changed.
A fuse with a current rating of less than 10A will be considered to have been placed
under stress.
3.4.6 Signal Head Poles
This test must be performed on the pole in question where LV (230V) is present on the
pole. After gaining access to the signal head terminations connect the Red probe of
the test instrument to a phase conductor termination (either red or green aspect
conductor). Connect the earth test probe (Black probe) to the test points listed below.
When the aspect to which the instrument is connected illuminates read the earth fault
loop impedance.
Test points
Earthed metal of pole itself e.g. unpainted inside face
667/HE/20664/000
Page
38
Issue 18
TS Traffic Installation Testing
Wait Indicator box
Near sided signals
Tactile indicators (if metal)
Maximum acceptable values
This is based on the rating of the fuse protecting the pole and the
dimming voltage, which is normally the signal fuse. For a T400 controller
it is the 10Amp fuse on the lamp switch PCB: this is actually a fast acting
fuse which blows faster than a BS1361 fuse - for the purposes of this test
treat as a general purpose fuse under the IET Regulations. For some
legacy controllers it may be the controller fuse. See Table 2 on page 23
for values (current controllers) or Table 3 on page 41 for legacy
controllers. See also explanatory notes following Table 2.
If the whole controller is protected by 300mA RCD, the maximum Earth
Loop Impedance should be as calculated in section 3.4.4. and not exceed
100 .
3.5
TESTING OF RCDs
3.5.1 Preparation
Controller should be switched on and operating normally.
This test is performed with the RCD test meter, see 3.2 Test Equipment. The test
measures the actual disconnection time of the RCD. The following tests are required to
be completed in both polarities, some meters automatically change polarity for
consecutive tests e.g. Seaward RC750, others will require a manual selection change.
3.5.2 30mA trip current RCD protecting maintenance socket
Nuisance trip test: Connect the RCD tester into the maintenance socket. Set the test
trip current to 15mA (30mA / 2), select positive half cycle, press test button: The RCD
should not trip. Reset the RCD, select negative half cycle and repeat test. (I n/2 test)
Connect the RCD tester into the maintenance socket. Set the test trip current to 30mA,
press test button: The maximum allowable trip time is 0.2 seconds. Reset the RCD,
select negative half cycle and repeat test. (I n test)
Reset the RCD. Set the trip current to 150mA and re-test: The maximum allowable trip
time is 0.04 seconds. Reset the RCD, select negative half cycle and repeat test. (5I n
test)
If any test other than the first 15mA test fails replace the RCD. If only the nuisance trip
test fails consult the client, if they use the socket to power permanently installed
equipment they may wish it replaced.
667/HE/20664/000
Page
39
Issue 18
TS Traffic Installation Testing
3.5.3 300mA RCD protecting whole controller (if fitted)
Trip the 300mA RCD using test button on RCD. (The whole controller will switch off –
check for relevant permissions).
Switch off the Master switch and connect to the line and neutral terminals using an
adapter lead. (Either use probes or connect into the line and neutral termination
points.) Connect the Earth to a convenient good Earth.
Nuisance trip test: Connect the RCD tester into the maintenance socket. Set the test
trip current to 150mA (300mA / 2), select positive half cycle, press test button: The
RCD should not trip. Select negative half cycle and repeat test. The RCD should not
trip. (I n/2 test)
Reset the RCD. Set the test trip current to 300mA and perform test, maximum allowable
trip time 0.2 seconds (i.e. 200msecs). (I n test)
If the test fails replace the RCD.
3.6
CORE INSULATION TESTING
3.6.1 Preparation
Switch off the controller/isolate the signals.
Disconnect both ends of the suspect core (controller and pole).
If the core links between many poles it will be easier to disconnect the other side of the
terminal blocks in each pole, e.g. disconnecting the lamp transformers. Then the whole
cable run can be tested.
3.6.2 Test
With the suspect core isolated, connect the red test lead of the Megger test instrument
to the core. Then connect black test lead to each of the cores in the same cable in turn
and test the impedance between the suspect core and other cores. It should be greater
than 12M . If less, replacement of cable is recommended.
3.7
CORE TO CORE LOOP RESISTANCE CONTROLLER TO POLE
3.7.1 Preparation
Switch the controller off and/or isolate the signals.
If the fault is common to signals in all signal posts, start the tests described below from
the signal post nearest the controller. Otherwise work on the post where the fault is
present.
Disconnect the two cores to be tested from the pole top, connect the two cores together
into a spare terminal at the pole top. Disconnect any transformers or other equipment
from the cores throughout the complete run. Disconnect the associated cores at the
667/HE/20664/000
Page
40
Issue 18
TS Traffic Installation Testing
controller, if the cables radiate from one pole to many, the cores must be disconnected
at all of the "many" before testing.
(It may be necessary to perform further loop resistance tests to check all branches of
cabling, if cables to other poles radiate from one pole rather than all in one long chain).
If only one core is suspect, another suitable core should be selected to form the loop
for this test.
667/HE/20664/000
Page
41
Issue 18
TS Traffic Installation Testing
3.7.2 Tests
Connect a resistance meter between the two cores at the pole. The resistance should
be no greater than those stated below. If it is, then all pole terminations should be
checked. If all pole terminations are all right, perform further loop resistance checks at
each pole, working out along the cable run from the controller until the particular cable
at fault is isolated.
Before testing, zero the meter.
1mm2 Resistance
1.5mm2 Resistance
@ 25 C (round trip)
@ 25 C (round trip)
Expected CPC
resistance (armour)
36.92
24.68
7.8
1 Km
18.46
12.34
3.9
500 metres
9.23
6.17
1.95
250 metres
4.61
3.08
0.98
125 metres
2.77
1.87
0.59
75 metres
1.85
1.25
0.39
50 metres
0.74
0.5
0.16
20 metres
0.37
0.25
0.08
10 metres
o
o
Approximate
distance to signal
TABLE 1
‘Expected CPC resistance’ is the typical value of resistance of the metal cable
sheath/armouring for 8-core 1mm2 cable. Larger cables have lower CPC values.
3.8
DC RESISTANCE CHECKS ON LAMP TRANSFORMERS (TS supplied signal heads
only)
3.8.1 Preparation
Disconnect the lamp transformer primary wires from the pole termination blocks.
3.8.2 Tests
The lamp supply (signal) fuses in the controller may be blown if a lamp transformer
begins to break down. The transformer may be checked as follows.
Connect a meter set to measure resistance between the two primary leads of any
suspect lamp transformer. Expect a reading of between 35 and 50 - typically 42
should be obtained. Any transformer with a reading outside these limits should be
replaced.
667/HE/20664/000
Page
42
Issue 18
TS Traffic Installation Testing
3.9
NEUTRAL CONDUCTOR VOLTAGE DROP TEST
This test only applies to non LED signals. The test relies on a lamp transformer in the
signal head, so that the un-driven green ‘sees’ the signal head Neutral through the
lamp transformer.
Set the Multimeter or voltmeter to measure 250V AC (RMS) or greater. Select a phase
and wait until its green has just terminated. Measure the voltage between the controller
neutral and the green feed. The voltage should be no greater than 4V (RMS)
throughout the controllers cycle, except when the phase next goes to green. If the
voltage between the green feed and neutral is greater than 4V then do the following:
i)
Check all joints in the appropriate cable run, ensure that they are all tight and
none seriously corroded. Replace or tighten them as necessary.
If the fault still persists, then:
ii)
Check all joints in the appropriate neutral cable run, ensure that they are all tight
and none seriously corroded. Replace or tighten them as necessary.
iii)
Increase the number of conductors/cable cores used for the neutral,
or
iv)
Replace the cable that has failed the test.
Re-test the cable to ensure that corrective action taken has removed the problem.
667/HE/20664/000
Page
43
Issue 18
TS Traffic Installation Testing
4.
PERIODIC INSPECTION AND TESTING
4.1
INTRODUCTION
Periodic inspection and testing of installations is to be carried out at least annually.
This work will comprise careful scrutiny of the equipment and shall be carried out
without dismantling or with partial dismantling of equipment as required, supplemented
by testing to comply with BS7671 17th edition incorporating the following amendments:
Amendment No. 1:2011
Amendment No. 2:2013
Amendment No. 3:2015
4.2
CONTENT OF WORK
The work shall consist of the following:
i)
Check the condition of the outer case, posts and signals, base seal and the
earth bonding and wiring. These should be recorded as ‘good’, ‘poor’ or
‘requires work’.
ii)
Check all signal heads for correct alignment with their respective approaches,
and that they are tightened to the appropriate suppliers specification.
iii)
Check all pole top cable connections; ensure that they are sound, secure and
not seriously corroded.
iv)
Check that all top caps are fitted and are not damaged.
v)
Open the controller door and verify presence of Log Book and Site configuration
documents.
vi)
Verify correct operation, i.e. no fault lamps are displayed. If required by the
customer, download site data to the handset.
vii)
Check the bonding of all cables where connected via terminations. This is to be
done visually, checking for any fraying, discolouration and corrosion and by
giving each tail a short pull.
viii)
Cover the Solar Cell, wait for the signals to dim and measure the dim voltage.
ix)
Allow the controller to cycle, check the detectors are operating correctly by
waiting for demands and ensuring correct results from the demands.
x)
Allow Signals to cycle and check all lamps operate correctly.
xi)
Site Insulation Test and fuse inspection.
For the duration of this test, switch the mains supply Master Switch
to the OFF position. See Appendix E for the suggested method.
Ensure local procedures are observed when switching the mains
supply off. If the customer dictates that the P.I. should be completed
without powering off the controller then the tests in this section (insulation
test and fuse inspection) cannot be performed and this must be clearly
recorded on the P.I. form under ‘Agreed limitations including reasons’.
All fuses to be checked to ensure that the correct type and value is fitted e.g. the
DNO Fuse (in the Lucy Cut Out), master fuse, controller fuse, signal supply
fuse(s), box signs fuse and other fuses.
667/HE/20664/000
Page
44
Issue 18
TS Traffic Installation Testing
Cartridge fuses in DIN-rail style fuse-holders should be marked with the fuse
value and the fuse standard. For fuses in DIN-rail style holders record the BS
standard marked on the fuse under ‘Type’. Note that PCB-mounted fuses
(32x6.3mm, 20x5mm, blade fuses) are not marked with the fuse standard, only
the fuse value, but PCB-mounted fuses must be replaced with the correct
characteristic (e.g. quick-acting F or time-lag T, and ceramic-bodied highbreaking capacity if applicable). For PCB-mounted fuses, enter the fuse size
under ‘Type’.
Note: for accessing and/or checking the DNO fuse specific training and wearing
of appropriate PPE are required.
The Insulation test instrument must be set to 500 Volts. This will avoid false low
impedance readings that may be obtained using higher test voltages, which
trigger the EMC protection devices fitted to some modern equipment (including
TS LED Signals). BS7987 / HD638 section 8.6 (the European standard for
Traffic Signal systems) and IET regulations allow for testing at 500 Volts.
All switches and circuit breakers other than the Master Switch in the controller
will be set to the ON position (but note 30mA RCDs must be tripped off and
varistor modules will need to be disconnected for this test (see section 2.6 for
details).
Using the insulation tester set to the 500V range, connect the test leads; one to
both the line and neutral supply tails and the other to the earth tail. Test the
insulation resistance and record the result in the appropriate box on the P.I. Test
Results form (Appendix C).
The minimum acceptable value for these tests is 1M .
The installation can now be connected to the mains supply and powered up
ready for the P.I. tests to be completed.
SAFETY
During the following test, ensure that NOBODY is in contact with
the pole or cabinet under test. Poles should be tested in
sequence working from the controller outward.
xii)
Perform an Earth Loop Impedance Test of a single Live Core, as described in
2.8.5 (note connection of the earth test lead to the metal of the pole). Do this
for all poles and push buttons with LV supply. See Table 2 or Table 3 for
acceptable values.
xiii)
Perform an Earth Loop Impedance Test at the origin of supply in accordance
with section 2.8.4.
xiv)
For ELV only pole(s), calculate the ELI. Firstly measure the loop resistance of
cable core and CPC as described in 2.4.4, then calculate the ELI value for the
ELV only pole as described in 2.8.6 (do this for all poles and push buttons).
Confirm the calculated value is below 5.44 (value for 10A fuse at 230V).
Repeat above tests for all poles
Please see below for a table giving legacy controllers (see section 2.8.2 for current
controllers) followed by completion of the procedure
667/HE/20664/000
Page
45
Issue 18
TS Traffic Installation Testing
Table 3 Fusing and ELI of Legacy Controllers
Controller fuses and allowable Earth Fault Loop Impedance Zs @ 20°C
compensated for 70°C operation by Rule of Thumb Method from IET Regs
Master fuse
Controller fuse
Signal fuse
230v
240v
125.4v
518/4/90352/005 or 518/4/97056/012
ST700 Part number
518/4/90637/007
(TfL/
BS88/IEC60269 IEC60068/GAM T1
TCUG) Fuse standard
Amps
16
16
Max earth loop imp.
3.12
3.12
ST700
/ST750
MCB
Master
Switch
P110
P125
T70
Part number
BS No
Amps
Max earth loop imp.
516/4/97076/010
MCB type C
20
0.87
Part number
BS No
Amps
Max earth loop imp.
Part number
BS No
Amps
Max earth loop imp.
Part number
BS No
Amps
Max earth loop imp.
Circuit Breaker Type B
Part number
7A
Amps
Max earth loop imp.
518/4/97056/012
IEC60068/GAM T1
16
3.12
BS EN 60898
10
3.5
Rewireable
BS 3036
5
7.28 (for 0.4s)
Rewireable
BS 3036
30
2
Rewireable
BS 3036
30
2
Rewireable
BS 3036
30
2
Rewireable
BS3036
30
2
Part number
T200
Amps
Max earth loop imp.
Part number
Amps
Max earth loop imp.
Part number
Amps
Max earth loop imp.
667/HE/20664/000
167.2v 146.3v
518/4/90301/013
EN 60127 – 2/1
10
5.44
3.78
3.31
2.83
518/4/90301/013
EN 60127 – 2/1
10
5.44
3.78
3.31
2.83
518/4/97020/118
ULE 10480 and CSA LR29862
6.3
9.6
6.67
5.84
5
518/4/90624/016
EN60127-2/4
20
2.24
1.55
1.36
1.16
20A
T500
120v
518/4/90624/015
EN60127-2/4
15
3.12
2.17
1.9
1.62
15A
Part number
Fuse standard
Amps
Max earth loop imp.
Part number
BS No
Amps
140v
518/4/97020/120
ULE 10480 and CSA LR29862
10
5.44
3.78
3.31
2.83
10A
T400
160v
518/4/90637/003
BS1361/BS88
45
0.73
518/4/90638/003
BS1361/ BS88
15 or 16
Page
518/4/90638/005
BS1361/BS88
30 or 32
1.28
518/4/90352/004
BS 88
10
46
518/4/97020/120
EN 60127 – 2/1
10
5.44
3.78
3.31
2.83
Issue 18
TS Traffic Installation Testing
Max earth loop imp.
3.12
5.44
Note: Table 3 only covers legacy controllers - for current (more recent) controllers see
Table 2 in section 2.8.2 on page 23.
Only Siemens controllers are covered in this document. Third party controllers need
the equivalent information to be obtained from the third party manufacturer.
xv)
Open Push Button Housing, inspect and
if 230V lamp, switch signals on and perform an Earth Loop Impedance
Test at the lamp socket,
or if 50V, switch signals on.
xvi)
Close the controller door
xvii)
Complete the appropriate PI form (see Appendix C). If the customer requires
their own forms to be filled in, complete the customers forms in addition to those
in Appendix C.
xviii) Inspect site to ensure that there are no hazards, check signals are cycling
correctly.
The check list in Periodic Inspection Forms is to be completed, at the back of this
document in Appendix C.
667/HE/20664/000
Page
47
Issue 18
TS Traffic Installation Testing
5.
MINOR WORKS
5.1
INTRODUCTION
The minors works certificate (Appendix D), may be used for those works considered
minor and in general these are Pole Knockdowns, Vandalised Pushbuttons, Change of
Pole Cap assembly and Change of Controller case. Local authorities may have
different views on what is to be considered minor so the local requirements should be
checked first. The IET define minor works as additions, alterations or replacements that
do not add new circuits. The addition of a new phase would mean the provision of a
new circuit and could therefore not be covered using a minor works certificate.
667/HE/20664/000
Page
48
Issue 18
TS Traffic Installation Testing
APPENDIX A - PRECAUTIONS TO BE TAKEN WHEN PLANNING THE INSTALLATION
AND MAINTENANCE OF TRAFFIC CONTROL EQUIPMENT IN THE VICINITY OF LIGHT
RAPID TRANSPORT SYSTEMS.
Introduction
The details given in this Appendix are designed to assist in the planning of installation
and maintenance of traffic control equipment in the vicinity of LRT systems. Advice is
given on the prevention of accidental contact between LRT track or vehicles and street
furniture, which would permit traction current to return through the Traffic control
equipment earthing system.
Reference Documents
The following documents were consulted in the preparation of this Appendix:
GEC Alsthom Transportation Projects Limited report no. TPL25/S/026 – Earthing and
Bonding Policy for Manchester Metrolink.
GEC Alsthom Transmission and Distribution Projects Limited report no. S/Sdq 856 –
th
Metrolink Report on Touch Voltages for Phase 1 dated 19 October 1990. Reference
732/XREP27.
Background
LRT track and the vehicles running on it may be at a potential other than the local earth
potential. This is due to track resistance and the return traction current flowing through
it.
In the Manchester Metrolink system the highest track/vehicle potential, known as the
“touch voltage” is estimated to be 34.9V for trains crush loaded on minimum headway
and 109V under short circuit fault conditions. The fault is said to persist for a maximum
of 100ms.
The traction current is DC and the resulting track/vehicle potential is said to be safe for
humans from the touch voltage point of view.
However, the source impedance could be low and it is desirable to prevent the touch
voltage coming into contact with traffic control equipment street furniture and cables
that are bonded to the electricity supply earth.
Any contact could cause heavy currents to flow, which would give rise to excessive
temperatures in the earth conductors of the traffic control equipment, with resultant fire
and explosion risk.
The recommendations that follow are aimed at preventing this.
Spacing of Street Furniture from LRT Track and Vehicles
It is recommended that 3 metres separation should always be maintained between the
nearest points on street furniture and LRT track and vehicles.
This nearest point should take into account that the separation can be reduced when
vehicle and equipment doors are open.
667/HE/20664/000
Page
49
Issue 18
TS Traffic Installation Testing
The installation manuals for all street furniture including cabinets, poles, signals,
detectors, key switches and push buttons should be amended where necessary to
include this information.
Spacing of Cables from LRT Track
Vehicle detector loops and feeder cables may have to be laid under LRT tracks to
detect the passage of light rail vehicles.
The cables should be fully insulated and the installation procedure should ensure
adequate separation to prevent chafing due to track movements.
Pantograph zones
There are special requirements for insulation of top cap brackets and wait units on ELV
controllers situated close to Pantograph overhead power installations.
See
667/CC/46150/000, 667/CC/46150/001 and 667/CC/46150/002 for details. Refer also
to BS EN50122-1 ‘Railway applications – Fixed Installations – Electrical safety,
earthing and the return circuit’.
Avoiding Accidental Contact with Tools and Test Equipment
It is common practice to connect power tools and test equipment to the controller
maintenance socket. The case of the tools or test equipment will therefore be
connected to the controller earth and should not come into contact with the LRT track
or vehicles.
Neither the RCD if fitted, nor the mains supply fuse will provide protection against the
possible heavy current resulting from accidental contact.
Care must be taken when using metal ladders to gain access to above ground
detectors and signals heads to prevent making contact between the street furniture and
LRT track or vehicles. Installation and maintenance manuals should be amended
where necessary to include this information.
Isolation of Interface between LRT and Traffic Control Equipment
The design of the interface between remote LRT outstations and traffic control
equipment should be isolated so that it is not affected by different earth potentials at
the two sites. The isolation should apply to the signals conductors and any cable
armour or screen, so that earth leakage current cannot flow between the cabinets.
667/HE/20664/000
Page
50
Issue 18
TS Traffic Installation Testing
APPENDIX B - COMPLETION CERTIFICATE AND TEST RESULTS
(ELECTRICAL INSTALLATION CERTIFICATE)
6 Pages Follow
NOTE. The latest edition of BS7671 was issued on 1st January 2015 (BS7671: AMD3: 2015).
Enter this date in the form where it shows “BS7671 amended to …… (date)”.
667/HE/20664/000
Page
51
Issue 18
TS Traffic Installation Testing
TRAFFIC SIGNAL INSTALLATION COMPLETION
CERTIFICATE (BS7671) amended to ……………...(date)
Customer's Name / Title: .............................................................…
DETAILS OF THE INSTALLATION
Site Address:
..............................................................................………………………………………………….
……………………………………………………………………………………………………………………………..
EM/STS No: .................….
Customer Drawing No: ...................…
E xtent of installat ion covered by this certificate.
New Installation
Modification to
Installation
PARTICULARS OF THE INSTALLATION
Type of Supply:
TN-C-S
TN-S
TN-C
TT
IT
Protection is provided by Earthe d Equipotential bonding and automatic disconnection of the supply
Characteristics of the supply at the origin:
Nominal Voltage………....….V
Electricity Board Fuse Rating……….A
ELI (Ze) at origin .........................
Max prospective fault current measured .......................…A
Max Prospective Fault Current Provided by the supply Authority………….……….A
Cabling used
Tick if used
1. 0mm Nos Cores
Armour CSA
8
20
12
34
16
38
20
41
8
21
12
36
16
40
20
45
Tick if used
1. 5mm Nos Cores
Armour CSA
Master Supply fuse or circuit breake r
Type: BS………..…… Rating…….…..A
Lamp Supp ly (signal) fuse
Type: …………...…… Rating…….…..A
Regulatory Signs fuse or circuit breaker
Type: …………...…… Rating…….…..A
Solar Cell supply fuse or circuit breaker
Type: ……………...… Rating………...A
Residual current device protecting:Whole installation 300mA
Supply Pola rity
- Tested
Maintenance socket only 30mA
- Risk assessed, not tested
Basic Polarity Test OK
Siemens Mobility - Traffic Solutions
Sopers Lane, Poole, Dorset, BH17 7ER
Tel: +44 (0)1202 782000
Fax: +44 (0)1202 782331
Siemens Mobility - Traffic Solutions is a division of Siemens plc
Registered office, Siemens plc, Faraday House, Sir William Siemens Square, Frimley, Camberley,
GU16 8QD, England. Registered No. 727817
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
ELECTRICAL INSTALLATION CERTIFICATE
(REQUIREMENTS FOR ELECTRICAL INSTALLATIONS - BS7671 [IET WIRING REGULATIONS])
COMMENTS ON EXISTING INSTALLATION IN CASE OF MODIFICATION
DESIGN FOR Junction design including positioning of equipment and equipment Selection
I/We being the person(s) responsible for the design of the electrical installation (as indicated by my/our signatures below),
particulars of which are described above for Junction design including positioning of equipment and equipment Selection,
having exercised reasonable skill and care when carrying out the design hereby CERTIFY that the design work for which I/we
have been responsible is to the best of my/our knowledge and belief in accordance with BS 7671, amended
to................................(date) except for the departures, if any, detailed as follows:
Details of departures from BS 7671 as amended (Regulations 120.3, 133.5):
The extent of liability of the signatory or the signatories is limited to the work described above as the subject of this Section and Certificate.
For the DESIGN of the installation:
For and on Behalf of Client
Signature: .............................................
Date: ...........................
Name (BLOCK LETTERS):......................................................... Designer No 1
DESIGN FOR Selection of Cable, Cable Routing and Installation of said Junction cabling
I/We being the person(s) responsible for the design of the electrical installation (as indicated by my/our signatures below),
particulars of which are described above for Selection of Cable, Cable Routing and Installation of said Junction cabling,
having exercised reasonable skill and care when carrying out the design hereby CERTIFY that the design work for which I/we
have been responsible is to the best of my/our knowledge and belief in accordance with BS 7671, amended
to................................(date) except for the departures, if any, detailed as follows:
Details of departures from BS 7671 as amended (Regulations 120.3, 133.5):
The extent of liability of the signatory or the signatories is limited to the work described above as the subject of this Section and Certificate.
For the DESIGN of the installation: For and on Behalf of Siemens Mobility - Traffic Solutions, Sopers Lane, Poole Dorset BH17 7ER
Signature: .............................................
Date: ...........................
Name (BLOCK LETTERS):......................................................... Designer No 2
FOR CONSTRUCTION / Installation
I/We being the person(s) responsible for the construction of the electrical installation (as indicated by my/our signatures below),
particulars of which are described above, having exercised reasonable skill and care when carrying out the construction hereby
CERTIFY that the construction work for which I/we have been responsible is to the best of my/our knowledge and belief in
accordance with BS 7671, amended to ................................(date) except for the departures, if any, detailed as follows:
Details of departures from BS 7671 as amended (Regulations 120.3, 133.5):
The extent of liability of the signatory is limited to the work described above as the subject of this Certificate.
For CONSTRUCTION of the installation: For and on Behalf of Siemens Mobility - Traffic Solutions, Sopers Lane, Poole Dorset BH17 7ER
Signature .................................................................................................................................................. Date
Name (BLOCK LETTERS) .........................................................................................................................
Constructor
FOR INSPECTION & TESTING
I/We being the person(s) responsible for the inspection & testing of the electrical installation (as indicated by my/our signatures
below), particulars of which are described above, having exercised reasonable skill and care when carrying out the inspection &
testing hereby CERTIFY that the work for which I/we have been responsible is to the best of my/our knowledge and belief in
accordance with BS 7671, amended to ..............................(date) except for the departures, if any, detailed as follows:
Details of departures from BS 7671 as amended (Regulations 120.3, 133.5):
The extent of liability of the signatory is limited to the work described above as the subject of this Certificate.
For and on Behalf of Siemens Mobility - Traffic Solutions, Sopers Lane, Poole Dorset BH17 7ER
For INSPECTION AND TEST of the installation: Signature: ............................................................................ Date: .......................................................
Name (BLOCK LETTERS): ................................................................................................... Inspector
NEXT INSPECTION
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
I/We the designer(s), recommend that this installation is further inspected and tested after an interval of not more than 1 year.
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
INSTALLATION TEST RESULTS
Test Equipment Used
TGP Number
Multimeter:
Low Resistance Ohmeter
Insulation Tester:
Earth Loop Impedance Tester:
RCD Tester:
Inductance tester:
Other:
Insulation Test of Complete Installation
(2.6.2)
500V
M
30mA RCD
Test (2.9)
15mA
30mA
150mA
Next Calibration due
Time
300mA RCD Time
Test (2.9)
ms 150mA
ms 300mA
ms
ms
ms
Cable Test Results
Cable Run:
From
To
Core to Core
Insulation
Min 20MOhm
(2.2.2)
Loop
Resistance
Core to Core
(2.4.2)
(R1 + R1)
Loop
Resistance
Core to CPC
(2.4.3 or 2.4.4)
(R1 + R2)
CPC
Resistance
(2.4.5)
(R2)
Earth Loop
Impedance
(2.8)
Zs
Mains Main Earth
Live Terminal
Mains Distribution
Live panel
Mains Castellated
Live bar or CET
bar as
fitted
Mains Front door
Live bare metal
Mains Rear door
Live bare metal
Mains Front panel
Live / Racking
earth
Mains Maintenance
Live socket
Earth pin
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
Place an ‘*’ in the top left corner for an ELI value that has been calculated for
an ELV Pole.
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
Cable Test Results
Cable Run:
From
To
Core to Core Loop
Insulation
Resistance
Min 20MOhm Core to Core
(2.2.2)
(2.4.2)
(R1 + R1)
Loop
Resistance
Core to CPC
(2.4.3 or 2.4.4)
(R1 + R2)
CPC
Resistance
(2.4.5)
(R2)
Earth Loop
Impedance
(2.8)
(Zs)
Place an ‘*’ in the top left corner for an ELI value that has been calculated for
an ELV Pole.
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
INSTALLATION DETECTOR TEST RESULTS (2.10.1)
Loop
Designation
Resistance to
Earth of Loop
and Feeder
Min R = 10M
Series Resistance
of Loop
and Feeder Cable
Max R = 8
Inductance
of Loop
and Feeder
30-500 H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
NEUTRAL CONDUCTOR VOLTAGE DROP TEST (2.11)
Phase
Voltage Drop
1 (A)
2 (B)
3 (C)
4 (D)
5 (E)
6 (F)
7 (G)
8 (H)
9 (I)
10 (J)
11 (K)
12 (L)
13 (M)
14 (N)
15 (O)
16 (P)
17 (Q)
18 (R)
19 (S)
20 (T)
21 (U)
22 (V)
23 (W)
24 (X)
25 (Y)
26 (Z)
27 (A2)
28 (B2)
29 (C2)
30 (D2)
32 (E2)
32 (F2)
Results of additional tests if required by the customer:
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
APPENDIX C - P.I. ELECTRIC TEST CERTIFICATE
(ELECTRICAL INSTALLATION CONDITION REPORT)
6 Pages Follow
NOTE. The latest edition of BS7671 was issued on 1st January 2015 (BS7671:
AMD3: 2015). Enter this date in the form where it shows “BS7671 amended to ……
(date)”.
667/HE/20664/000
Page
61
Issue 18
TS Traffic Installation Testing
TRAFFIC SIGNAL ELECTRICAL INSTALLATION CONDITION
CERTIFICATE (BS7671 amended to …………………(date)
Customer:
............................................................…
Site Reference No. …………….
Site Address ..............................................................................……………………………………………
………………………………………………………………………………………….......................................
Log Book present in controller Y or N
Controller Type: ………………….
Supply:
TN -C- S
TN - C
TN-S
TT
EM/STS No: .................………………
Document present in controller Y or N
SUPPLY AND PROTECTION DETAILS
Supply Polarity
- Tested
IT
- Risk assessed,
not tested
Agreed limitations including reasons:
(e.g. if customer mandates no switch-off of supply)
Site insulation @ 500V
Supply Voltage
Protection at Supply Cut Out
Fuse:
Type BS………….. Rating ………..A
ELI Measurement
V
DIM Voltage
V
……………..…..
Protection at Master Switch
Fuse:
Type BS………….. Rating ………..A
Protection Device at Final Sub Circuit (Pole)
Lamp Supply (Signal) Type……..….
Rating……….A
Reg Sign Supply Type ….…..…….
Rating……….A
Solar Cell Supply Type ….…..…….
Rating……….A
ELI Measurement
……………………
See Attached Sheet for ELI measurements
See Attached Sheet for ELI measurements
See Attached Sheet for ELI measurements
See Attached Sheet for ELI measurements
Protection is provided by earthed equipotential bonding and automatic disconnection of the supply
REMARKS
Risk assessment carried out. No known electrical work done to affect Supply Polarity, so polarity not checked. (Cross out, if inapplicable).
Remarks need to be classified with one of the following codes: C1 = Danger present. Risk of injury. Immediate action required. C2 = Potentially dangerous – urgent remedial action required. C3 =
Improvement recommended.
Overall assessment of suitability of installation for continued use:
SATISFACTORY
UNSATISFACTOR
Y
(tick one)
I/we certify that the said work as indicated on this form has been carried out
Name (Block
Letters)................................................
Position .......................................................
Signature................................................................ Date..............................................................
..
For and on behalf of:
Siemens Mobility - Traffic Solutions
Sopers Lane Poole Dorset BH17 7ER
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
Tel: +44 (0)1202 782000
Fax: +44 (0)1202 782331
Siemens Mobility - Traffic Solutions is a division of Siemens plc
Registered office, Siemens plc, Faraday House, Sir William Siemens Square, Frimley, Camberley,
GU16 8QD, England. Registered No. 727817
Subject to any necessary remedial action being taken, I/we recommend that the
installation is further inspected and tested after an interval of not more than 1 year.
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
P.I. TEST RESULTS
Test Equipment Used
TGP Number
Multimeter:
Low Resistance Ohmmeter
Insulation Tester:
Earth Loop Impedance Tester:
RCD Tester:
Other:
Insulation Test of Complete Installation (2.6)
M
500V
Cabling Used
Tick If Used
1.0 mm Nos Cores
Armour CSA
30mA RCD
Test (2.9)
15mA
30mA
150mA
Next Calibration due
Time
300mA RCD
Test (2.9)
ms 150mA
ms 300mA
ms
Time
ms
ms
Tick If Used
8
20
12
34
16
38
20
41
1.5 mm Nos Cores
Armour CSA
8
21
12
36
16
40
20
45
Cable Test Results
Test Point
Pole Number
Wait/Ped. Signal
Earth Loop Impedance
Results of additional tests
if required by the
customer:
CONTROLLER CABINET
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
Cable Test Results Continued
Cable Test Results
Test Point
Pole Number
Wait/Ped. Signal
667/HE/20664/000
Earth Loop Impedance
Page
of
Issue 18
TS Traffic Installation Testing
CONTROLLER CABINET
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
CABLE TEST RESULTS FOR ELV ONLY POLES
FOR PERIODIC INSPECTION
(Where CPC values are measured and the ELI value is calculated)
Cable Test Results
Cable Run:
From
To
Loop
Resistance
Core to Core
(2.4.2)
(R1 + R1)
Loop
Resistance
Core to CPC
(2.4.3 or 2.4.4)
(R1 + R2)
CPC
Resistance
(2.4.5)
(R2)
Earth Loop
Impedance
(2.8)
(Zs)
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
CHECK LIST FOR NEW INSTALLATION OR PERIODIC INSPECTION
(INSPECTION SCHEDULE)
FOR ENGINEER TO COMPLETE DURING THE INSPECTION
TICK TO INDICATE SATISFACTION WITH INSPECTION - DELETE IF
NOT APPLICABLE
TYPE OF INSPECTION (tick one):
NEW INSTALLATION
PERIODIC INSPECTION
1.
Outer Case Condition
2.
Condition of Posts & Signal heads
3.
Condition of Base Seal
4
Protection against direct contact
4.1
Check all insulation is in good condition
4.2
Check all covers are in place and not
damaged in any way
4.3
Check that all barriers and enclosures are in
place and not damaged e.g. the cabinet, all
pole caps, pushbuttons housings, signal
heads / housings, feeder pillars etc.
5.
Condition of Earthing as protection against
indirect contact. ADS (Automatic Disconnection
of Supply).
5.1 Main Earth Terminal
5.2 Main Equipotential Earth Bonding
Conductors
Earthing between panels etc within the
cabinet, and to Pushbuttons etc
5.3
CPC (Armouring terminations etc)
6.
Condition of Internal Wiring
7.
Dimming Functioning
8.
Detectors Operational
9.
RAM Battery date fitted
10.
Checked no faults displayed
11.
Log book and site configuration documents
present
12.
Correct Controller operation verified
667/HE/20664/000
Y/N
Y/N
Y/N
Page
of
Issue 18
TS Traffic Installation Testing
13.
Check security of connections
14.
Check results from demands
15.
After signals cycle, check all lamps are ok
16.
Switch Signals Off and then On again
17.
Earth Loop Impedance tests
18.
Inspect Push Button housing
19.
Connection of conductors
20.
Identification of conductors
21.
Routing of cables in safe zones or protected
against mechanical damage
22.
Connection of single-pole devices for
protection or switching in phase conductors
only
23.
Adequacy of access to switchgear and
equipment
24.
All fuses checked to ensure that the correct
type and value is fitted e.g. master fuse,
controller use, signal supply fuse, box signs
fuse and other fuses.
25.
Site insulation test
26.
Labelling of protective devices, switches and
terminals
27.
Presence of danger notices and other
warning signs
28.
Controller door closed
29.
Complete PI Form
30.
Inspect for hazards and that signals are
cycling correctly
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
APPENDIX D - MINOR ELECTRICAL INSTALLATION WORKS CERTIFICATE
1 Page Follows
NOTE. The latest edition of BS7671 was issued on 1st January 2015 (BS7671:
AMD3: 2015). Enter this date in the form where it shows “BS7671 amended to ……
(date)”
667/HE/20664/000
Page
71
Issue 18
TS Traffic Installation Testing
PART 1 : Description of minor works
1.Description of the minor works : ...............................................................................................................
2.Location/Address : ...................................................................................................................................
3.Date minor works completed : ..................................................................................................................
4.Details of departures, if any, from BS 7671 (as amended)…………………(Date)
...................................................................................................................................................................
...................................................................................................................................................................
...................................................................................................................................................................
...................................................................................................................................................................
PART 2 : Installation details
1. System earthing arrangement (where known):
TN-C-S
TN-S
TN-C
TT
IT
th
(For an illustration of earthing system arrangements see regulation 312.2 of 17 Edition of IET regulations)
2. Method of protection against indirect contact: ......................................................................................................
3. Protective device for the modified circuit :
Type BS .....................................
Rating ................ A
4. Comments on existing installation, including adequacy of earthing and bonding arrangements : (see IET Regulations 17th
Edition, regulation 132.16.)
...................................................................................................................................................................
...................................................................................................................................................................
PART 3 : Essential Tests
1. Earth continuity :
satisfactory
2. Insulation resistance:
Line and Neutral/earth ...................... ……….M
3. Earth fault loop impedance ............................. …..……
4. Polarity :
satisfactory
5. RCD operation (if applicable) : Rated residual operating current I n ............mA and operating time of ............ms (at
I n)
PART 4 : Declaration
1. I/We CERTIFY that the said works do not impair the safety of the existing installation, that the said works have
been designed, constructed, inspected and tested in accordance with BS 7671 (IET Wiring Regulations), amended
to ..........................(date) and that the said works, to the best of my/our knowledge and belief, at the time of my/our
inspection, complied with BS 7671 except as detailed in Part 1 above.
3. Signature: ...........................................................
2. Name: ..................................................................
For and on behalf of: ............................................
Position: ..............................................................
Address: ..............................................................
.............................................................................
Date: ...................................................................
.............................................................................
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
667/HE/20664/000
Page
of
Issue 18
TS Traffic Installation Testing
APPENDIX E - START UP ROUTINE
The following pages contain the text of document 4/CC/1057/000
incorporated into this handbook.
667/HE/20664/000
Page 74
Issue 18
TS Traffic Installation Testing
Siemens Mobility - Traffic Solutions
Sopers Lane,
Poole,
Dorset,
BH17 7ER
METHOD STATEMENT
FOR
JUNCTION SWITCH OFF AND START-UP ROUTINE
Prepared: T.R. Lelliott
Approved: J.P. Burgess
Function: Technical Services Manager
Function: Engineering Manager
THIS DOCUMENT IS ELECTRONICALLY HELD AND APPROVED
Issue: 2.00
Change Ref:
Date: 25 July 2001
This is an unpublished work the copyright in which vests in Siemens Mobility - Traffic
Solutions, a division of Siemens plc. All rights reserved.
The information contained herein is the property of Siemens Mobility - Traffic Solutions and
is supplied without liability for errors or omissions. No part may be reproduced or used
except as authorised by contract or other written permission. The copyright and the foregoing
667/HE/20664/000
Page 75
Issue 18
TS Traffic Installation Testing
restriction on reproduction and use extend to all media in which the information may be
embodied.
667/HE/20664/000
Page 76
Issue 18
TS Traffic Installation Testing
1
Introduction
1.1
Purpose
This document defines the procedure for switching off and starting up Traffic Signal
controllers in the presence of live running traffic. This procedure is not appropriate for
installations which are being commissioned to be put into service for the first time.
1.2
Scope
This procedure is relevant for use on both Intersection and Pedestrian Controllers, and will
be applied in the event that signals are to be switched off to allow maintenance activity to be
undertaken.
In the event that the owners/operators of the signals (normally the Local Authority) have
local instructions covering this activity, then those instructions take precedence over this
document.
2
Training and Safety
2.1
This procedure is to be carried out only by competent persons. Satisfactory
completion of the appropriate TS training course, or extensive work experience to the
satisfaction of the Regional Line Manager are necessary pre requisites.
2.2
High visibility clothing to the required TS standards is to be worn at all times when
working on the highway.
3
Procedure
To Switch Off and /or Start Up a traffic signals installation the following sequences apply:
Switch Off:
Switch controller to manual
Establish main traffic flow
Switch off signals.
Start-Up:
Switch “Signals On/Off” switch to OFF
Switch main controller supply ON, make sure automatic control is selected,
Switch main controller supply OFF.
Switch “Signals On/Off” switch to ON
Switch main controller supply ON.
This ensures that for all makes of controllers, they will start up in the start up stage
4
Risk Assessment
Risk assessment for this procedure is deemed to be generic, and the procedure defined in
section 3 above has been identified as the safest method for all installation configurations.
It is inappropriate to attempt to identify risks related to driver behaviour.
667/HE/20664/000
Page 77
Issue 18