Answer / prakash gokhale

While opening and closing the breaker the arc occures
between the contacts of the breaker. To resist the arc and
to protect contacts some arc quenching medium is used. In
ACB air and in VCB vaccume is used as arc quenching medium.

Answer / mohammad farman khan

While opening and closing the breaker the arc occures
between the contacts of the breaker. To resist the arc and
to protect contacts some arc quenching medium is used. In
ACB air and in VCB vaccume is used as arc quenching medium.

VCB= VACUUM CIRCUIT BREAKER and use for medium voltage
RATING 630A to 1250 A

ACB= Air circuit Breaker and use for LV side from 1600A to
3200A.

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