I am working on modification of protection system to suit a temporary transformer. Initially the system was designed for a 60MVA 132/33kv YNynd11 and A CDG66 O/C relay with a MCAG 14 REF relay are installed on the 132kV side. Main CTR = 500/1 connected in Y configuration. OC set at 0.75A i.e...
I came across an MCSU relay(GEC) setting which puzzled me. The Core balance CT ratio is 0.5/0.0075 and the pick up was set at 1.5 with a plug setting of 1. What is the actual primary pick-up current in this case?
I thought it would be 1.5x CTR(66.67)= 100A, but the source of the feeder where...
I want to detect a 2 Amp Primary SEF on an isolated 3 phase underground circuit. My primary current will be around 700-800 amps maximum when starting a series of water pumps. There is a requirement that the SEF at the 11kV outgoing feeder towards the Pump Station should be limited to 2 Amps. I...
