SURGE PROTECTIVE DEVICES SPECIFICATIONS
SURGE PROTECTIVE DEVICES
1. INTRODUCTION
In order to ensure safety of people, protection of equipment and, to a certain
extent, continuity of supply, insulation co-ordination aims at reducing the
likelihood of equipment dielectric failure. Several components can be used to
limit and/or eliminate the surges.
This document provides general specification for the surge protective devices
(SPDs) to be installed in LV electrical systems.
SPDs shall be installed near the origin of the installation or in the main
switchboard assembly, however additional SPDs might be necessary to protect
sensitive equipment and when the distance from the main SPD to the next
distribution board is big (> 30m). These secondary SPDs shall be coordinated
with the upstream SPDs.
2. SPECIFICATIONS
2.1. STANDARDS
The accomplishment of the following standards are required:
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
STANDARD
EN 61643-11 Type 1, Type 2 and Type 3. Surge protective devices
connected to low voltage power distribution systems. Part 1 .
This is the European variation of IEC 61643-1 which is mandatory in
European countries
IEC 61643-1 Class I, Class II and Class III test Edition 2 ( march
2005): Surge protective devices connected to low voltage power
distribution systems. Part 1
IEC 60364-4-44 Electrical installations of buildings - Part 4-443:
Protection against overvoltages of atmospheric origin or due to
switching
IEC 60364-5-53 Electrical installations of buildings - Part 5-534:
Devices for protection against overvoltages
IEC 60529 Degrees of protection provided by enclosures (IP code)
2.2. CERTIFICATIONS
2.2.1
2.2.2
Both EN & IEC Certifications are
required.
CE marking (to IEC61643-1 Class I,
Class II and Class III test)
METHOD
Third Party Lab
Third Party Lab
or self certified
A safety mark of conformity shall be required: ÖVE, NF, KEMA,….
SPD Engineering Specification Latest.doc
1
SURGE PROTECTIVE DEVICES SPECIFICATIONS
2.3. SURGE CURRENT RATINGS AND PROTECTION LEVELS
Iimp (Type 1)/ Imax (Type 2):
The value of Iimp shall not be less than 12,5kA for each mode of protection [IEC
60364-5-534].
In case the connection type 2 is used (see 2.7.1.1) the value of Iimp (N-PE)
shall not be less than 50 kA for three-phase systems and 25 kA for single-phase
systems [IEC 60364-5-534].
The preferred values for the impulse current for Type 1 test SPD are 35 /50 kA
(L-PE or L-N), 50kA (N-PE single phase systems when using connection
type 2) and 100kA (N-PE three phase systems when using connection type
2)
The preferred values for the maximum surge current rating Imax for Type 2
tests SPDs are 8kA, 20kA, 40kA and 65kA.
In:
The nominal discharge current In shall not be less than 5kA for each mode of
protection [IEC 60364-5-534].
Up:
The protection level of the protective device (Up) shall not be higher than the
level of overvoltage category II (2,5kV) [IEC 60364-4-443].
If sensitive electronics is to be protected the protection level shall not be higher
than 1,5 kV.
Uc:
For a 230/400V network it is recommended the Maximum Continuous Operating
System (Uc) to be no less than 340 V.
Response time:
The response time of Type I SPD shall be no more than 1μs, the response time
of Type 2 SPD shall be no more than 25 ns.
2.4. MECHANICAL REQUIREMENTS
SPD Engineering Specification Latest.doc
2
SURGE PROTECTIVE DEVICES SPECIFICATIONS
2.4.1
Housing Material
2.4.2
Required Housing
Markings
2.4.3
2.4.5
Terminal Connection
End of Life Indicators
2.4.6
Mounting Method
2.4.7
Shock, Impact,
Vibration
Enclosure Protection
2.4.8
Housing material must conform the
necessary standards (including self
flame-extinguishing characteristics),
• Compliance to IEC 61643-1 Section
6.1.2
• Test certification marks
35mm2 is preferred
All products (except products to be
connected N-PE) will have an End of Life
visual indicator. The indication shall be
LED or mechanical. If LED is used must
be ON for normal operation (green color).
When reach the end of life LED or
mechanical indication must be Red.
Standard Snap on 35 mm DIN Rail
mounting.
Reference IEC 60068
Comply with IEC 60529 IP20 rating
2.5. ENVIRONMENTAL REQUIREMENTS
2.5.1
2.5.2
2.5.3
Minimum Operating Range
Relative Humidity
Altitude
-5 ° C to +40 ° C
5% to 90%
2000 Meters minimum without derating
2.6. ELECTRICAL REQUIREMENTS
2.6.1
Remote
Indication
Optional. When required use Dry Contacts (250
VAC 1.5A, 125V 3A desired, min. 0.25 Amps at
250V required).
2.6.2
Thermal
Protection
Short circuit
Protection
Thermal fusing is required for MOVs. Not
required for GDTs
External dedicated circuit breaker to the SPD is
required to guaranty the continuity of service
and electrical installation safety in case of short
circuit inside the SPDs.
47 Hz to 62 Hz
2.6.3
2.6.4
2.6.5
System
Frequency
Breaker
Coordination
Provide coordinated disconnect device
requirements which will be put in the literature
and on product as required by the manufacturer
recommendations.
SPD Engineering Specification Latest.doc
3
SURGE PROTECTIVE DEVICES SPECIFICATIONS
3 INSTALLATION RECOMMENDATIONS
3.1 SPD configuration depending on the grounding system:
3.1.1 TT systems (connection type 2):
3.1.2 TN-S, TN-C systems:
For TN-S, TN-C systems it can be used connection type 2 (see 2.7.1.1) or
alternatively connection type 1 as per below (if there is significant distance
between the N-PE bonding point it shall be used and additional SPD N-PE):
SPD Engineering Specification Latest.doc
4
SURGE PROTECTIVE DEVICES SPECIFICATIONS
3.1.3 IT systems:
3.2 Connecting conductors:
The length of the connecting conductors from the lines to the SPD added to the
cable conductor from the SPD to the main earth terminal shall be less than 0,5
m (IEC60364-5-53).
The cross section of the cables shall not be less than 4 mm².
When there is a lightning protection system, for type 1 products the cross
section shall not be less than 16 mm ².
SPD Engineering Specification Latest.doc
5
SURGE PROTECTIVE DEVICES SPECIFICATIONS
3..3 External dedicated protection:
An external dedicated protection will be installed to protect against overcurrent
and consequences of SPD failure and to optimize the continuity of service.
.
SPD Engineering Specification Latest.doc
.
.
6