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This is 480 3-phase. There would be no possibility of an outlet and zero branch circuits. The operators were subjected to the shock by accident. They did not intentionally touch both machines just to see if the voltage was present. The operation is very dusty. MAybe the extreme dust is conducting?
Just trying to rule out the possibility of someone hacking a leg for something. I'm guessing you would have cleared any major dust during initial t/s. How many grounding points between each machine and ground system? It sounds like one or both machines has an open in the egc somewhere. Your meter will tell you which leg is shorting, then where the ground is compromised. I hope they're ok with you taking the machines out of service for a bit-i hate when the brass won't ok a little down time... be safe.
 

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The thing about 35 volts is a teaser- my first thought was ghost voltage. It almost looks like a shared neutral but no. I wonder if someone incorrectly branched somewhere off one of the legs for an outlet or something.
They thought it was correct, and may not have been directly addressed by NEC...? Won't know until the culprit is found, though.

This is 480 3-phase. There would be no possibility of an outlet and zero branch circuits. The operators were subjected to the shock by accident. They did not intentionally touch both machines just to see if the voltage was present. The operation is very dusty.
The second one didn't know the first one had been "shocked"? Okay, that changes it. I read it as "Hey Bubba, I jus got shawked, let me holl your beer an' you see what you git!"

Controls are probably 120v which are more exposed and more likely to get damaged then the main phases.
35V controls? (48V with a drop?) Possibly? From another source that isn't bonded to the machines?

We recently discovered through replacement that our metering for our lift station was on a separate panel/feeder than the submerged pumps. That's going to be corrected soon.
 

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