IEC 62271-100(2017),High-voltage switchgear and controlgear – Part 100: Alternating-current circuit-breakers.
This amendment includes the following significant technical changes
the rated TRV has been replaced by a rated first-pole-to-clear factor;
the rated time quantities have been moved to Clause 5(Design and construction)and areno longer ratings. The determination of the break time has been moved to lEC 62271-306;
the number of test specimens has been removed;
new test procedure for test-duty T100a;
TRVS for circuit-breakers having a rated voltage of 52 kV and below used in effectively earthed neutral systems have been added;
6.111(capacitive current switching) has been rewritten;
a number of informative annexes have been moved to lEC TR 62271-306.
This part of IEC 62271 is applicable to a c. circuit-breakers designed for indoor or outdoor installation and for operation at frequencies of 50 Hz and 60 Hz on systems having voltagesabove 1000V.
It is only applicable to three-pole circuit-breakers for use in three-phase systems and single-pole circuit-breakers for use in single-phase systems. Two-pole circuit-breakers for use in single-phase systems and application at frequencies lower than 50 Hz are subject to agreement between manufacturer and user.
This standard is also applicable to the operating devices of circuit-breakers and to their auxiliary equipment. However, a circuit-breaker with a closing mechanism for dependent manual operation is not covered by this standard as a rated short circuit making- current
ot be specified, and such dependent manual operation may be objectionable because of
safety considerations.