Bizarre voltage reading

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  #1  
Old 07-22-07, 08:30 AM
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Bizarre voltage reading

Hello

I am in the process of a major kitchen remodel project in Minnesota.
I've done some wiring in the past, adding circuits to a basement that I finished, some minor remodeling rewiring, and other minor things, but nothing to the extent of my current project - we are gutting out and remodeling the entire kitchen, adding a 1/2 bath to the adjacent mudroom and will be upgrading the 125A fuse panel to a 200A breaker panel as well as adding a subpanel in the garage. I have a neighbor who is a general a contractor and he's offered to help me with any questions, but he was stumped by my recent finding.
The rambler I'm, working on was built in 1966, most of the (copper) wiring is in green field and I will be replacing much of it with Romex as well as adding new circuits with Romex.
I disconnected the refrigerator outlet, and subsequently lost power at two outlets across the room. I figured that they were in a parallel series with the missing outlet, so I wasn't surprised, but to verify this, I took my Fluke 110 multimeter to the first of these two and found voltage readings of 120 between the hot and ground (right and center), 5V hot to neutral, and 32V neutral to ground (Left to center). When I inserted an AW Sperry plug-in tester, it indicated an open neutral. On the other outlet, I got reading of 5V hot to neutral, 23V neutral to ground and 31V ground to neutral with no light indication using the plug-in tester.
What do you make of this? Any advice would be helpful.
Thank you
Brian
 
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  #2  
Old 07-22-07, 09:16 AM
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You are using a digital meter, aren't you? Worthless in this situation, especially with an open neutral. It is not reading true voltage in an unloaded condition.

Use a Wiggy, Vol-Con, or similar solenoid-type tester or a neon tester.

If you want true voltage readings, you need an analog meter, or a load.
 
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Old 07-22-07, 11:03 AM
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Like Mac says, you are getting "phantom" voltage using the digital meter. Digitals are great in their own arena, but this ain't one of them. A mechanical means is better.
 
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Old 07-22-07, 01:59 PM
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You are reading phantom voltage, as the others have told you.

If you are getting advice from someone who has no idea what those voltages mean, stop getting advice from him. Phantom voltage should be known and understood by anyone providing advice in the home wiring field.
 
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Old 07-22-07, 09:33 PM
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Thanks.
I've not heard of phantom voltage, but I think I can understand the concept. I'm guessing that once I restore the circuit, I will get a normal reading again.
Brian
 
  #6  
Old 07-23-07, 04:18 AM
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Google the term "phantom voltage" and you can learn all about it. It is the real voltage induced upon a wire by the electromagnetic field of the wires that run near it.
 
  #7  
Old 07-23-07, 06:42 AM
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In addition to the other causes mentioned for phantom voltages, when you complete and otherwise 'open' circuit by connecting the internal resistance of a voltmeter across 2 points, then some current can flow, and some kind of voltage reading will appear on the meter.

A cheap analog meter may present a resistance on the order of 100,000 ohms. A better analog meter may be 1 to 5 million ohms. A digital meter probably at least 10 million ohms. These differences account for the different ways any meter can "fool" you.
 
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