Electrical accessories - Residual current operated circuit-breakers with integral overcurrent protection for household and similar uses (RCBO's) - Part 1: General rules

This Standard applies to residual current operated circuit-breakers with integral overcurrent protection functionally independent of, or functionally dependent on, line voltage for household and similar uses (hereafter referred to as RCBO's) for rated voltages not exceeding 440 V a.c., rated currents not exceeding 125A for fixed installation and rated short-circuit capacities not exceeding 25 000 A for operation at 50 Hz or 60 Hz. These devices are intended to protect people against indirect contact, the exposed conductive parts of the installation being connected to an appropriate earth electrode and to protect against overcurrents the wiring installations of buildings and similar applications. They may be used to provide protection against fire hazards due to a persistent earth fault current, without the operation of the overcurrent protective device. RCBO's having a rated residual operating current not exceeding 30 mA are also used as a means for additional protection in the case of failure of the protective means against electric shock. This standard applies to devices performing simultaneously the function of detection of the residual current, of comparison of the value of this current with the residual operating value and of opening of the protected circuit when the residual current exceeds this value, and also of performing the function of making, carrying and breaking overcurrents under specified conditions. Special precautions (e.g. lightning arresters) may be necessary when excessive overvoltages are likely to occur on the supply side (for example in the case of supply through overhead lines). This standard also applies to RCBO's obtained by the assembly of an adaptable residual current device with a circuit-breaker. The mechanical assembly shall be effected in the factory by the manufacturer, or on site, in which case the requirements of annex G shall apply. It also applies to RCBO's having more than one rated current, provided that the means for changing from one discrete rating to another is not accessible in normal service and that the rating cannot be changed without the use of a tool. Supplementary requirements may be necessary for RCBO's of the plug-in type. Particular requirements are necessary for RCBO's integrated in one unit with a socket-outlet or designed exclusively for being associated locally with a socket-outlet in the same mounting box. This standard does not apply to: RCBO's intended to protect motors, RCBO's the current setting of which is adjustable by means accessible to the user in normal service; RCBO's having more than one rated current. The requirements of this standard apply for normal environmental conditions. Additional requirements may be necessary for RCBO's used in locations having severe environmental conditions. RCBO's including batteries are not covered by this standard.