IEC 60947-2 Ed. 6.0 b:2024 PDF

This document applies to circuit-breakers, intended to be installed and operated by instructed or skilled persons, the main contacts of which are intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V AC or 1 500 V DC; it also contains additional requirements for integrally fused circuit-breakers.

This document also applies to circuit-breakers with ratings at or below 1 000 V AC, additionally having one or more ratings above 1 000 V AC but not exceeding 1 500 V AC.

It applies whatever the rated currents, the method of construction or the proposed applications of the circuit-breakers may be.

Circuit-breakers per this document are suitable for isolation.

The requirements for circuit-breakers which are also intended to provide residual current protection are contained in Annex B.

Additional requirements for circuit-breakers intended for connection of aluminium conductors are contained in Annex D.

The additional requirements for circuit-breakers with electronic overcurrent protection are contained in Annex F.

The additional requirements for circuit-breakers for IT systems are contained in Annex H.

The requirements and test methods for electromagnetic compatibility of circuit-breakers are contained in Annex J.

The requirements for circuit-breakers not fulfilling the requirements for overcurrent protection are contained in Annex L.

The requirements for modular residual current devices (without integral current breaking device) are contained in Annex M.

The requirements and test methods for electromagnetic compatibility of circuit-breaker auxiliaries are contained in Annex N.

The requirements for instantaneous trip circuit-breakers are contained in Annex O.

The requirements and test methods for DC circuit-breakers for use in photovoltaic (PV) applications are contained in Annex P.

The requirements and test methods for circuit-breakers incorporating residual current protection with automatic reclosing functions are contained in Annex R.

Supplementary requirements for circuit-breakers used as direct-on-line starters are given in IEC 60947-4-1, applicable to low-voltage contactors and starters.

The requirements for circuit-breakers for overcurrent protection for household and similar installations, and designed for use by uninstructed persons, are contained in IEC 60898 series.

The requirements for circuit-breakers for equipment (for example electrical appliances) are contained in IEC 60934.

For certain specific applications (for example traction, rolling mills, marine service, downstream of variable frequency drives, use in explosive atmospheres), particular or additional requirements can be applicable.

NOTE 1 Circuit-breakers can have dedicated accessories.

NOTE 2 Circuit-breakers which are dealt with in this document can be provided with devices for automatic opening under predetermined conditions other than those of overcurrent and undervoltage as, for example, reversal of power or current. This document does not deal with the verification of operation under such pre-determined conditions.

The object of this document is to state:
a) the characteristics of circuit-breakers;
b) the requirements for circuit-breakers with reference to:
1) operation and behaviour in normal service;
2) operation and behaviour in case of overload, operation and behaviour in case of shortcircuit, including co-ordination in service (selectivity and back-up protection), as well as the operation and behaviour in case of ground-fault;
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 3 For cybersecurity requirements, see IEC TS 63208.