Standards Development

Scope

This part of IEC 60947 series applies to semiconductor circuit-breakers, intended to be installed and operated by instructed or skilled persons, the main terminals of which are intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V a.c. or 1 500 V d.c.This standard covers the following different types:–        Semiconductor Circuit-Breakers (SCCBs) have semiconductor switching elements and, for isolation function mechanical switching elements connected in series.–        Semiconductor Hybrid Circuit-Breakers (SCHCBs) have semiconductor switching elements and mechanical switching elements in parallel and, in addition, for isolation function, mechanical switching elements connected in series.In this document where the term “Circuit-Breaker” only is used, it applies to both types.It applies whatever the rated currents, the method of construction or the proposed applications of the circuit-breakers may be.The object of this document is to state:a)      the characteristics of circuit-breakers;b)      the conditions with which circuit-breakers shall comply with reference to:1)      operation and behaviour in normal service;2)      operation and behaviour in case of overload and operation and behaviour in case of short-circuit, including co-ordination in service (selectivity and back-up protection);3)      dielectric properties;4)      requirements on electromagnetic compatibility, where applicable.c)       tests intended for confirming that these conditions have been met and the methods to be adopted for these tests;d)      information to be marked on or given with the circuit-breakers.NOTE For cybersecurity requirements, see IEC TS 63208