Oil Circuit Breaker

The arrangement permits two advantages firstly the current breaking chamber requires a small volume of oil which is just enough for arc excitation secondly, the amount of oil to be replaced as the in the supporting chamber does not get contaminated the arc.
The single phase oil circuit breaker, there are only one moving contact. But HTM branch dehiwala has three phase oil circuit breaker. There are six moving contacts. Their supporting chamber and circuit breaking chamber made having metal. But single phase OCB supporting chamber made porcelain. Three phase OCBis very heavily we can’t moving it very easily.