Remote racking great save

[richxtlc]

I was thinking about this last night and went over how we did our checks when we had an outage and were installing breakers. With the bus de-energized, we racked in and racked out all the breakers to do both positive and negative checks on the breaker and the cubicle to verify that all the interlocks were in fact working.

Wasn't this part of the installation testing, the previous replies mentioned the various tests that were done on the breaker, but none were mentioned on the cubicle. With the number of breakers that were being racked in I would assume that the bus was dead.

This looks like a case of complacency and a defective interlock combined to cause this event.

 

[zog]

I was thinking about this last night and went over how we did our checks when we had an outage and were installing breakers. With the bus de-energized, we racked in and racked out all the breakers to do both positive and negative checks on the breaker and the cubicle to verify that all the interlocks were in fact working.

Wasn't this part of the installation testing, the previous replies mentioned the various tests that were done on the breaker, but none were mentioned on the cubicle.

I am not sure what thier procedures entailed, but I agree with you on what should be covered.

With the number of breakers that were being racked in I would assume that the bus was dead.

Nope, live bus, hence the arc flash.

This looks like a case of complacency and a defective interlock combined to cause this event.

Exactly