The old phantom 60 volts

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Old 12-14-04, 10:29 AM
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The old phantom 60 volts

Hi Guys:

A guy has this situation:

A set of outlets has 102v hot-to-neutral, but 60v from hot-to-ground and 60v ground-to-neutral.

My take was that he has a poor ground connection and gave suggestions on tracking it down.

I believe that the 60v ground-to-neutral is irrelevant and doesn't enter into the problem. True or not? If true, how do I explain this reading to him? Is this inducted voltage, or is there another phenomenon at work?

I know this has been discussed before, but I can't seem to search the archives anymore.
 
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Old 12-14-04, 10:40 AM
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It is most likely phantom voltage. If he wants the nitty-gritty, point him to this web site, or just tell him to take our word for it.

I suggest that everybody have one of those $8 outlet testers in their toolbox, the kind that plugs in and has three lights on it. These testers aren't so easily fooled by phantom voltage.

Chance are none of the voltage readings taken to ground can be trusted. Did you really mean 102 hot to neutral, or was that 120?
 
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Old 12-14-04, 10:57 AM
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John:

Oops. Got to proofread better. 120v is correct.

Thanks for the link.

Why do people ask for advice and then argue with you when give it?
 
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Old 12-14-04, 04:12 PM
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Classic voltage reading of an open neutral.
Or he could be using a digital meter and getting a Phantom voltage. What are the voltages when nothing is plugged into the circuit and when a lamp is plugged in a turned at the receptacle you are testing.
 
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Old 12-14-04, 04:18 PM
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It's not an open neutral. There are two symptoms inconsistent with an open neutral reading: 60 volts hot to ground, and 120 volts hot to neutral. There is no way an open neutral could cause a 60 volt reading from hot to ground, unless the ground was also open.
 
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Old 12-14-04, 07:11 PM
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simple idea have you taken the device out of the box and seen what the wires are doing.

what kind of device is this?
 
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Old 12-15-04, 03:53 AM
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It's a series of outlets in a recently added home office.

My understanding is that its all the outlets in the room, which are on the same circuit.

I don't know whether this was a new run, or run from an existing source.

My advice was:

1. check the connections at the source. That would be the panel or the source outlet.
2. Go to the first outlet in the office and check the connections there.
3.Take a reading at this outlet. Use a good quality meter that ignores inductive readings and put the contacts on the wire ends, not the device.
- If you get 120v hot-to-ground here, start working your way downstream.
- If you get 60v (or 0v) hot-to-ground, your problem is upstream and you may have a broken ground from the source to here.

Just got an update:
This was run from an existing circuit. I'm betting the original circuit had the problem before it was extended.
 
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Old 12-15-04, 07:14 AM
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If the house is old, the circuit may have never had a grounding connection.
 
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