30-10-2012, 06:11 PM
EHV CIRCUIT BREAKERS
EHV CIRCUIT BREAKERS.pptx (Size: 1.19 MB / Downloads: 47)
Introduction:
A circuit breaker is piece of equipment which can
Make or break a circuit either manually or by remote control under normal conditions.
Classification by voltage:
Low voltage breakers – Less than 1kv
Medium voltage breakers - 1kv to 52kv
High voltage breakers - 52kv to 765kv
Ultra high voltage breakers - Greater than 765kv
Oil circuit breakers:
Oil circuit breakers can be further classified with reference to the quantity of oil used as
Bulk oil circuit breaker (BOCBs)
Minimum oil circuit breaker (MOCBs)
In BOCBs, the interrupting unit is placed in a tank of oil at earth potential and the incoming and outgoing conductors are connected through insulator bushings. In MOCBs on the other hand, the oil requirement could be minimized by placing the interrupting units in insulating chambers at live potential on an insulator column.