Karma already caught up with me- I took the PE exam today, and there were 2 questions dealing specifically with this, which I was really not expecting! So taking the time to think it through again well enough to explain it has already paid off [Linked Image]

I just wish there had been more NEC questions and less freaking high-voltage fault analysis... this fall's test did not play to my strengths, that's for sure.

WFO: we had that happen once a couple years ago on a 480V plant- breakers tripping left and right, popping like popcorn! Was bad news. Turns out, the contractor, despite reassuring us TWICE that he had metered and verified rotation, had indeed swapped phases at the UPS bypass switch. The only good news was it wasn't my fault, nor my problem, as I didn't work there yet. But oh, I hear about it every time anyone suggests an online test vice scheduling an outage...

[This message has been edited by SteveFehr (edited 10-27-2006).]