stratford
Electrical
- Oct 3, 2005
- 40
Dear all. On iste we have a three winding step-up transformer connceted to the grid of 400kV via a disconnector and a circuit breaker. The disconnector is between Step-Up transformer and circuit breaker. When we de-energize from the 400kV grid we are instructed to open first the circuit breaker and then open the disconnector in a period of 10 seconds maximum after the opening of the circuit breaker. I cant quite understand this logic. Can you help me on that?