Answer / karna

Under voltage coil means it will energized when supply
available, closing coil means it will operate when we are
giving closing command at that time it will operate , shunt
trip means it will operate when we are giving trip command
manually or through fault. CLOSING COIL OPERATE MEANS WE
WILL GET OUTPUT SUPPLY FROM THE ACB TERMINALS , SHUNT TRIP
COIL OPERATE MEANS IT WILL DISCONNECT THE OUTPUT SUPPLY OF
THE ACB TERMINALS. IF UV COIL USED IN ACB MEANS WITHOUT
INCOMING SUPPLY WE CAN'T CLOSE THE ACB.

Answer / nirmalraj

cc used for closing the breaker contact, tc used for trip/open
the breaker contact and uv coil used for spring charge
interlock. if no supply manual spring charge is possible,
supply is present manual spring charge is not possible

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