BS EN 60947-2:2017+A1:2020

This part of IEC60947 series 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 1000V a.c. or 1500V d.c.; it also contains additional requirements for integrally fused circuit-breakers. Circuit-breakers rated above 1000V a.c. but not exceeding 1500V a.c. may also be tested to this standard. It applies whatever the rated currents, the method of construction or the proposed applications of the circuit-breakers may be. The requirements for circuit-breakers which are also intended to provide earth leakage protection are contained in AnnexB. The additional requirements for circuit-breakers with electronic over-current protection are contained in AnnexF. The additional requirements for circuit-breakers for IT systems are contained in AnnexH. The requirements and test methods for electromagnetic compatibility of circuit-breakers are contained in AnnexJ. The requirements for circuit-breakers not fulfilling the requirements for over-current protection are contained in AnnexL. The requirements for modular residual current devices (without integral current breaking device) are contained in AnnexM. The requirements and test methods for electromagnetic compatibility of circuit-breaker auxiliaries are contained in AnnexN. The requirements and test methods for d.c. circuit-breakers for use in photovoltaic (PV) applications are contained in AnnexP. The requirements and test methods for circuit-breakers incorporating residual current protection with automatic reclosing functions are contained in AnnexR. Supplementary requirements for circuit-breakers used as direct-on-line starters are given in IEC60947‑4‑1, applicable to low-voltage contactors and starters. The requirements for circuit-breakers for the protection of wiring installations in buildings and similar applications, and designed for use by uninstructed persons, are contained in IEC60898. The requirements for circuit-breakers for equipment (for example electrical appliances) are contained in IEC60934. For certain specific applications (for example traction, rolling mills, marine service, downstream of variable frequency drives, use in explosive atmospheres) particular or additional requirements may be necessary. NOTE Circuit-breakers which are dealt with in this standard can be provided with devices for automatic opening under predetermined conditions other than those of over-current and undervoltage as, for example, reversal of power or current. This standard does not deal with the verification of operation under such pre-determined conditions. The object of this standard is to state: the characteristics of circuit-breakers;the conditions with which circuit-breakers shall comply with reference to: operation and behaviour in normal service; 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); dielectric properties;tests intended for confirming that these conditions have been met and the methods to be adopted for these tests;information to be marked on or given with the apparatus.