scope:

This part of IEC 60947 applies to the types of equipment listed in 1.1 (a.c. and d.c. contactors) and 1.2 (a.c. motor-starters) whose main contacts are intended to be connected to circuits the rated voltage of which does not exceed 1 000 V or 1 500 V d.c. Starters and/or contactors dealt with in this standard are not normally designed to interrupt short-circuit currents. Therefore, suitable short-circuit protection (see 9.3.4) shall form part of the installation, but not necessarily of the contactor or the starter. In this context, this standard gives requirements for: - contactors associated with overload and/or short-circuit protective devices; - starters associated with separate short-circuit protective devices and/or with separate short-circuit and integrated overload protective devices; - contactors or starters combined, under specified conditions, with their own short-circuit protective devices. Such combinations, e.g. combination starters (see 3.2.7) or protected starters (see 3.2.8) are rated as units. Circuit-breakers and fuse-combination units used as short-circuit protective devices in combination starters and in protected starters shall comply with the requirements of IEC 60947-2 and IEC 60947-3, as the case may be.