# Need help with the math on this one...



## Shawn (Nov 30, 2007)

I went to switch out a couple of receptacles in a commercial building and this is what I found. I found what I assumed was the breaker for the receptacle, (my test light went out.) And switched out the receptacle and buttoned it up. I then went to the other one and found it had a couple devices that were plugged in but not lit. I assumed it was shut off as well. 
Well I'm stripping the wires and happen to touch the neutral and ground together and I get a spark. Ok, I figured some clown switched the wires around up in a box somewhere. But then it turns out Ive got 118 volts on the hot and the neutral! But they are on the same phase, so of course they cancel each other out. So I go back and turn on the breaker and now Ive still got 118v on the neutral and now have 205 on the hot. But 118 across them. This building has 120/208 and 480/277 circuits and one panel was labeled 240/120. Basically I cant figure out what phases and voltages would come up with this combo? Anybody run into this?


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## 480sparky (Sep 20, 2007)

Since this is (I am assuming here) a standard receptacle, there should not be any 480/277 voltage involved.

Let me guess.... is the neutral a grey wire?


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## Shawn (Nov 30, 2007)

The neutral was white, and it was a standard 15amp duplex rec. Also in this same building. A guy asked me if I had any of the breaker locks, because at night his computer was being shut off. So I look at the panel and there are a couple in there that are being used. And he goes "no its in this panel" And I **** you not its a 277 lighting panel. I didn't believe him so I shut it off and just like he said the the computer on his desk shuts off. I look around and there was a couple of transformers up by the ceiling, I assume they came out of the transformer and ran a circuit??? I just shook my head. And said a couple of choice words.


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