Hello, I am just preparing my self for a university interview and struck on the 11kv ring main unit system network. I just know that ring main unit has total three breakers, fuses and use to supply a power to any load/ building without any interrupt. But i am not be able to visualize the connections, either Ring main unit getting power from two different power sources? or there is always one feeder in complete ring circuit??? I would be highly thanks full of you help me.