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Mike G.
Mike G., Master Electrician
Category: Electrical
Satisfied Customers: 7369
Experience:  Proven Professional 48 years Experience
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In a sub panel with buried wire im getting 240 volts across

Customer Question

in a sub panel with buried wire im getting 240 volts across both legs but when i test each leg to ground im getting 0 on one and the full 240 on the other
Submitted: 10 months ago.
Category: Electrical
Expert:  Mike G. replied 10 months ago.

Hi, I'm Mike and I'll be assisting you. Did you test at the main breaker for the sub panel?

Customer: replied 10 months ago.
I tested the breaker at the main panel that feeds the sub panel it test ok, 120 volts each leg and 240 across both legs ,when I went to sub panel I took the wires out of the main breaker and neutrsl out of box my reading was 240 across both legs but 0 on one and 240 on the other, I did notice the wire coming out of house underground. It is the individual wires but they had the two hits in conduit and the neutral running beside the conduit, if that neutral corroded under ground and became open could this be why
Expert:  Mike G. replied 10 months ago.

That's exactly what happened. Your feeder should be replaced with 4 wires. 2 hots, 1 neutral and 1 ground. All conductors should be in conduit.

Customer: replied 10 months ago.
Could I run 3 wire then put in grounding rod out at sub panel
Expert:  Mike G. replied 10 months ago.

You need 4 wires and a ground rod for sub panels. That's code.

Customer: replied 10 months ago.
Ok thanks,appreciate your help
Expert:  Mike G. replied 10 months ago.

Anytime, you're welcome.

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