prSRPS CLC/TS 51643-12:2026

Low-voltage surge protective devices - Part 12: Surge protective devices connected to low-voltage power distribution systems - Selection and application principles

Scope

This Technical Specification describes the principles for selection, operation, location and co ordination of SPDs to be connected to 50 Hz to 60 Hz a.c. power circuits and equipment rated up to 1 000 V r.m.s..
NOTE 1 This Technical Specification deals only with SPDs and not with surge protective components (SPCs) integrated inside equipment.
NOTE 2 Additional requirements may be necessary for special applications such as electrical traction, etc.
This TS specifies requirements for protection of electrical installations against transient overvoltages of atmospheric origin transmitted by the supply distribution system including direct strikes to the supply system and against switching overvolages.
This TS gives guidance for protection against transient overvoltage due to direct or nearby lightning strokes on the structure, which is in addition to HD 60364-4-443.
NOTE 1 For risk management for protection against transient overvoltage due to direct or nearby lightning strokes on the structure, see EN 62305-2.
This TS does not apply to installations where the consequences caused by overvoltages affect:
1) structures with risk of explosion;
1) structures where the damage may also involve the environment (e.g. chemical or radioactive emissions).
Requirements for protection against transient overvoltages transmitted by data transmission systems are not covered by this TS. See CLC/TS 61643-22.