The reason I ask is that the VT supplies 3off under voltage relays connected in a 2oo3 tripping logic. The relays are set with a trip point if 80% nominal voltage. Therefore assuming a loss of a bus bar phase I was curious whether the UVR would operate.
It seems as if one relay will operate but...
It is a 3 phase Tx. It is not 3 x 1 phase units. The primary neutral is floating, the secondary neutral is earthed solidly. The only loads connected to the secondary are 3off single phase under voltage relays.
Thanks for the help so far.
Bill
The transformer is a protection VT on an 11kV sw/bd.the secondary star point is solidly connected to earth.
It is a 3ph device wound on 1 core but I am cannot confirm the core construction but likely to be 3legs.
Thanks
I have a scenario where I have an 11kV board with a bus bar connected 11/0.11kV V.T.
The V.T. Is wired Y-Y(g) I.e. Only the secondary neutral is earthed.
My query is this:--
What will the secondary voltages be if the primary sees a loss of one phase. I.e. Assume that the Red phase 11kV bus...
