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...
KenAlmon,
Where I hail from this sort of protection is usually called 'interzone' protection. This is if we assume that by 'primary' of the GSU you mean the HV bushings as opposed to the LV bushings. If the GSU CT is on the LV side then the scheme would be transformer differential protection...
