ECN Forum Forums Photo Discussion Forums Photos for General Discussion 4" RMC vs Utility Current

Wow!,
This looks like a big job.
Just a silly little question, were the wires in the 3 conduits above the one that blew out, checked or tested to make sure that they weren't damaged from the heat?.

Hi Mike



All wires replaced.

The switchgear was checked by a manufacturers (GE) technician.

Bob

[This message has been edited by iwire (edited 12-27-2004).]

Mike, not a silly question at all. As Bob said all cables were replaced. Yes it was a big job. We started out with five guys at 6AM. Brought in 2 more at 10AM, and 3 more at 4PM. We all left at midnight with everything packed up. Except for the painters coming the next day you would never have known we were there.

I'll take a stab at the cause: Insulation damage on the conductors in the bottom conduit where they emerge through the bushing.

It looks like the bonding-bushing lugss on the other three conduits could be pressed into their respective conductors, too.

I try to "pre-bend" wires to keep them centered in, or at least not jammed against, the conduits from which they emerge.

I say it was the bullet hole in the conduit in picture #3. What ever blew it was vaporized early in sceme of things.

Bump...

Now THAT is a real eye opener to what can happen !!!That would have been something pretty spectacular to see... That would put some fireworks displays to shame!

Some years ago when I used to work at the supplier a building down the road had its main underground service short out and it also wiped out the padmount transformer ( Service was 400A 120/240V 1 phase, that consisted of 2 ducts containing 3/0 TWH in paralell)... One of the ducts shorted and burned the conductors bare from the transformer to the fault... Turns out when they were pulling out the damaged conductors, a chunk of broken fish tape was drawn out right where the fault appeared to have originated, and had been tangled in there since day one.. About 15 years if not a bit longer..

A.D

Bob, Could I have your permission to use your photo. Of course I would give credit.

DHester:
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