Ratings of circuit breakers
1- Rated voltage: The
maximum operating voltage at normal conditions.
2- Rated frequency.
3- Rated insulation voltage:
The designed insulation voltage.
4- Rated power-frequency
withstands voltage: the maximum power frequency voltage that the insulation can
withstand.
5- Rated impulse withstands
voltage: The maximum impulse voltage that insulation can withstand.
6- Rated continuous current.
7- Rated breaking current:
The maximum value of r.m.s symmetrical current that the C.B. can interrupt
safely at a power factor of 0.2 - 0.25.
8- Rated making current: The
maximum value of current that can pass in the C.B.at closing.
9- Rated short-time current:
The maximum r.m.s symmetrical current that can pass in the C.B. for one second.
