High current low voltage loop splitting via MODs

[mbrooke]

How well does parallel buss splitting work with standard MODs at the 345 and 400kv voltage level?

 

[Bugman1400]

What do you mean by standard MODs? I think most 345kV substations have a double bus config. Whats your question, specifically?

 

[mbrooke]

What do you mean by standard MODs? I think most 345kV substations have a double bus config. Whats your question, specifically?

MOD= motor operated disconnects. My question is can these break parallel full load current current. Picture breaker and a half for example... one of the breakers is stuck and can not open. To avoid de-energizing an entire buss or taking neighboring bay out of service, can the MODs be opened under full load? The key to this is that it will not be interrupting full voltage since the two buses are theoretically shorted together through the other normally closed breakers. The MOD will only see parallel current and the voltage drop across the bus, so it might be something like 450 amps at 100 volts.

 

[Bugman1400]

MOD= motor operated disconnects. My question is can these break parallel full load current current. Picture breaker and a half for example... one of the breakers is stuck and can not open. To avoid de-energizing an entire buss or taking neighboring bay out of service, can the MODs be opened under full load? The key to this is that it will not be interrupting full voltage since the two buses are theoretically shorted together through the other normally closed breakers. The MOD will only see parallel current and the voltage drop across the bus, so it might be something like 450 amps at 100 volts.

Sorry, I misread your original post. Standard MODs cannot (should not) break any load. However, I have seen and there are videos on Youtube of a standard MOD being used to do just that....break load current for a breaker that failed to open on one pole (don't know if it was 345kV or 500kV).

 

[mbrooke]

Sorry, I misread your original post. Standard MODs cannot (should not) break any load. However, I have seen and there are videos on Youtube of a standard MOD being used to do just that....break load current for a breaker that failed to open on one pole (don't know if it was 345kV or 500kV).

Its ok


My understanding is you can (think, but not sure) provided the switches do not have arc whiskers that make first / break last.