I went to view and take pics of a big job gone bad last week.
A 4000 amp 480v service (one of 4 services to this building). When they tried to energize the main switch, there was a second or two and than the show began. They tried to open the switch, but it welded closed and finally a cable burned clear. There was still power to the switch and the POCO had to kill their end to deenergize the service.
It all happened because they transposed the neutral for phase A.
It destroyed all kinds of equipment in the building, including Asco switches and other 'juicy' $$$$$ equipment and wiring. They are estimating $500,000.00 in damage.
OUCH!!
There are so many things that were wired incorrectly, I do not have the time or space to explain.
The big question being asked though is; how did they energize the service switch without any prior testing?
Pierre
