scope:

This part of 60898 applies to a.c. air-break circuit-breakers for operation at 50 Hz or 60 Hz, having a rated voltage not exceeding 440 V (between phases), a rated current not exceeding 125 A and rated short-circuit capacity not exceeding 25000 A. As far as possible, it is in line wit the requirements contained in IEC 60947-2. These circuit-breakers are intended for the protection against overcurrents og wiring installations of buildings and similar applicaitons; they are designed for use by uninstructed people and for not being maintained. They are intended for use in an environment with pollution degree 2. They are suitable for isolation. Circuit-breakers of this standard, with exception of those rated 120 V or 120/240 V (see table 1), are suitable for use in IT systems provided that the requirements of IEC 60364-4-473:1997 + A1:1998 are complied with. This standard also applies to circuit-breakers 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. This standard does not apply to - circuit-breakers intended to protect motors; - circuit-breakers, the current setting of which is adjustable by means accessible to the user.