Substation Short Circuit

[Mbrooke]

What would cause this? How would high voltage get into the control house? I'm guessing CT or VT short circuited internally?

https://www.youtube.com/watch?v=PQHTAhXsF1g

I have a fear of relay circuits now lol.

 

[Bill West]

A protection planner I knew had a piece of black glass on his desk. I think it used to be switchyard gravel, a 230kv CT had failed. In the control room the covers were blown off the relays. I take it some of the fault voltage or localized ground rise came in through the control cables. At college our professor had a couple guys check out 600v wire with a 15kv Hi-Pot set. The corona glowed but the insulation did not puncture right away. The jacket on the control cables would more than double the available insulation.

Bill

 

[Mbrooke]

Could be ground potential rise as well with a poor earthing grid. I see smoke rising from the ground near the control hut.