Answer / amit rajak

It is because it has very good arc extinguishing properties.
and which helps it to extinguish arc more rapidly. even arc
takes place in them only at very high voltages as vaccum
medium does not allow arc to take place.

advantages of VCB over OCB.
1.GOOD MAKING AND BRAKING CAPACITY
2.DOES NOT ALLOW ARC TO TAKE PLACE AT LOW VOLTAGES.
3.LOW MAINTENACE
4.FUEL REGULATION IS NOT NEEDED AS IN OIL CB.
4.CAN USED AT ALL VOLTAGES.
5.EFFICIENT ARC INTERRUPTION CAPACITY

Answer / sithi

arc extinguish is more fastly than OCB

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