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Old 10-29-2012, 08:47 PM   #1
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Shared Neutral - Open???

Got some funky electrical gremlins on a couple of circuits, well more exactly two circuits that share a neutral. Seems to me like an open neutral issue. I properly get 240v between the red and black hot wires, but down around 110 between either the black or red and the white neutral. I get 10-20 volts between white and ground. So something is up. Back at the panel checking between the neutral bar and the breakers I get 120 on each breaker when they are on. About .5v when they are off. When I turn one breaker on I get 120v between it and the neutral and then about 18v between the on that is off and the neutral bar!! So obviously something is wrong. Any idea what I can check or how to track down this issue? As best I can tell I have found the box that is the first one from the panel and was doing the testing there. any ideas?


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Old 10-29-2012, 09:36 PM   #2
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Sounds more like a ground issue than a neutral issue. If it was a neutral issue the voltage between the hot and neutral would not be equal.


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Old 10-29-2012, 10:07 PM   #3
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I think we would need more complete diagnostic testing to tell you exactly what's wrong, but it does sounds like a possible loose neutral connection. Have you tried tightening all the connections? Have you measured the neutral-to-ground voltage on other circuits, and between the busses in the panel?
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Old 10-30-2012, 05:56 AM   #4
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One sure sign of a neutral problem, the red/white and black/white voltages seesaw (while still adding up to about 240) when you turn on more lights or appliances on one side.
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Old 10-30-2012, 11:03 PM   #5
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what are you testing the voltage with ?
Remember digital meters can give eronious readings.
Test with an anologue type meter !Name:  anologue volt meter.jpg
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