SPD and external SCPD coordination table

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Contents


The table in Figure J37 below shows the coordination of disconnecting circuit breakers (external SCPD) for Type 1 and 2 SPDs of the Schneider Electric brand for all levels of short-circuit currents.
Coordination between SPD and its disconnecting circuit breakers, indicated and guaranteed by Schneider Electric, ensures reliable protection (lightning wave withstand, reinforced protection of impedant short-circuit currents, etc.)



Tableau chap J.jpg















































Fig. J37: Coordination table between SPDs and their disconnecting circuit breakers of the Schneider Electric brand
(1): All circuit breakers are C curve - (2): NG 125 L for 1P & 2P - (3): Also Type 2 (class II) tested

Coordination with upstream protection devices

Coordination with overcurrent protection devices
In an electrical installation, the external SCPD is an apparatus identical to the protection apparatus: this makes it possible to apply discrimination and cascading techniques for technical and economic optimization of the protection plan.

Coordination with residual current devices
If the SPD is installed downstream of an earth leakage protection device, the latter should be of the "si" or selective type with an immunity to pulse currents of at least 3 kA (8/20 μs current wave).

Note: S type residual current devices in conformity with the IEC 61008 or IEC 61009-1 standards comply with this requirement.
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