Could anyone please advise the opening times of the following two circuit breaker types when they are protected by self powered VIP300LL relays:
1. a CE6-T4 Ringmaster CB operating at 13.8 kV with 800/1 A CTs
2. a RM6 200 A CB operating at 22 kV with type CRa current sensors.
By opening time I...
Is there a formula which calculates the relative proportions of earth fault return current through:
1) an overhead earth wire strung on the same poles as the faulted line; and
2) the body of the earth.
I have seen results for item 1) which include one component of earth fault current in the...
