# House wiring problem

Page 4 of 6
• posted on April 4, 2010, 1:20 am

wrote:

If it doesn't light up visibly, but the voltage is still there (ANY voltage) it's still a problem. If the voltage is ZERO, it most likely is not a problem - just inductive or capacitive coupling.

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<%-name%>
• posted on April 3, 2010, 7:24 pm

Why not? You've got the floating wire lying right next to a 120v line for 50 feet or whatever the distance to the panel is. The voltage will be some large percentage of 120v. The current will be tiny (which is why DMM's show the voltage and analog meters don't). -- Doug

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<%-name%>
• posted on April 3, 2010, 6:44 pm

Because it is the CORRECT "low impedance" multimeter that can accurately measure line voltage circuits...
The cost is irrelevant, as long as the multimeter is the correct type, you will be able to properly measure for the actual presence or absence of hazardous line voltages...
~ Evan

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<%-name%>
• posted on April 3, 2010, 7:57 pm

Not only is cost irrelevant, but it's also a function of the person using the meter understanding some basic electricity and knowing how to interpret the readings. I've exclusively used digital VOMs for decades and never had any confusion. You could also make up an extra set of test leads with a 50K ohm resistor across them to reduce the input impedance.

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<%-name%>
• posted on April 4, 2010, 1:11 am
On Sat, 03 Apr 2010 00:17:08 -0800, David Nebenzahl

If the "long runs" were live, there is no reason the readings would not be accurate. However, a long run with a "dead" circuit paralleling a live one MAY read a voltage that would lead you to believe the circuit was connected and had a problem. If, in the OP's situation, for instance, the ground conductor actually DID exist, but was not connected to the panel ground, it is possible a "sensitive" or high impedence digital (or even VTVM) meter could indicate a voltage between the ground and either power-carrying conductor.

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<%-name%>
• posted on April 4, 2010, 3:50 am
On 4/3/2010 5:11 PM snipped-for-privacy@snyder.on.ca spake thus:

>

OK, plausible; but more than *50 volts* worth? I don't think so. A few volts, maybe.
--
You were wrong, and I'm man enough to admit it.

- a Usenet "apology"

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<%-name%>
• posted on April 3, 2010, 1:17 am
On Fri, 02 Apr 2010 15:37:24 -0800, David Nebenzahl

Depends a lot on the meter. With a Fluke or Amprobe meter, not very likely to have a problem, but with a \$9.99 (on sale for \$4.99) Harbour Fright special and many other cheap chinese DMMs it's almost a given.

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<%-name%>
• posted on April 3, 2010, 2:22 am
On 4/2/2010 5:17 PM snipped-for-privacy@snyder.on.ca spake thus:

>

Didn't you read what I wrote?
I told you I used my cheap-ass HF meter and *didn't* get any phantom readings. So no, not a given.
So far, nobody has been able to offer a plausible explanation.
--
You were wrong, and I'm man enough to admit it.

- a Usenet "apology"

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<%-name%>
• posted on April 3, 2010, 7:13 pm

There have been several (correct) attempts at an explanation. As I read your experiment, you tried on a correctly wired circuit and got correct readings. Just what you would expect.
Now, go unhook your ground wire at the panel. The hot line will induce a voltage in that wire that can be read by a high impedance meter as difference in voltage between ground and neutral. Is that plausible?
-- Doug

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<%-name%>
• posted on April 3, 2010, 3:30 am
wrote:

It is just as easy (maybe more so) for the Fluke or other high dollar meter to read the 'induced' voltage. I use the Fluke meters almost every day at work and have one at home. Most of the time if I want to get serious with the power wiring I will get my trusty Simpson 260. When dealing with some 480 volt 3 phase circuits running in conduit, you can pick up lots of odd voltages that are not really there. For example one circuit would read around 100 volts on the Fluke , light up a neon bulb tester, shock the fool out of you, and read about 30 volts on the Simpson. This is with the wires disconnected at the breaker.
It is not so much the meter, but the person that is using it. YOu have to know when the meter is 'lying' to you. Many people can not do that. Especially the people that seldom use a meter.

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<%-name%>
• posted on April 3, 2010, 5:20 am
Ralph Mowery wrote:

Sometimes the simplest tools are the best, like the good old Wiggy.
TDD

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<%-name%>
• posted on April 3, 2010, 8:20 pm

Sometimes they are. I have never used the Klein tester but can see where it may be a much beter circuit tester than some meters. Only problem is that it is a \$ 50 or so tool where the meters can be bought for \$ 5 to \$ 20 and be used for more things. A good old low power light bulb is very useful to run some checks with around the house.
For quick checks where I work I have a Fluke tester that is sort of like that. You just hook it up with the two test leads. If it is AC then anything from 24 to about 600 volts will light up some leds. It is DC then other lights will glow from about 12 volts up. And if there is a very low value resistance, another light will glow. Comes in handy for quick test when I may be working on some of the computer controlled equipment and may need to know if I have a relay contacts closed, or 24 volts , 120 volts or 480 volts active.
One thing I did not mention is that on a Simpson 260 and probably others like it is that if you suspect a phantom voltage you can move from one range to another and the meter will stay in about the same place on the scale. If the voltage is a solid voltage then the meter will go up or down a good bit to match the voltage with the scale on the meter.

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<%-name%>
• posted on April 4, 2010, 8:48 am
Ralph Mowery wrote:

One advantage is a Wiggy is pretty indestructible, as from drops, compared to a meter. I tend to use a neon test light for things like receptacles, partly because you can tell what wire is hot and it takes no space in my pocket.

Particularly after reading about arc-flash and 'sudden reconfiguration of the physical parts of a meter syndrome' I am more careful what I use. Measuring at a receptacle is not so bad, but I want something good if I am in a service panel, and something real good at high energy locations - 480V or high amps. There is a category rating for meters - Fluke (and others) use it.

Yea - simple but effective.

Ran across that once and it was one of more bizarre measurements I have seen.
--
bud--

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<%-name%>
• posted on April 3, 2010, 11:08 am
wrote:

Are you absolutely sure it is 59.4V and not 59.4 millivolts?
Yes, I am absolutely certain. My Fluke makes it unmistakably plain.
Dave

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<%-name%>
• posted on April 2, 2010, 9:05 pm
Dave wrote:

Hi, Get an analog meter to make a real reading. If you know the breaker which controls the outlet turn the power off and measure between ground and each lead. I bet neither one shows continuity meaning there is broken ground wire. Another way to look at is to connect a light bulb between either lead and ground. If the voltage is not phantom bulb will glow at half brightness or so.

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<%-name%>
• posted on April 2, 2010, 9:25 pm

OP said house was built in '49 or '50, there wouldn't have *been* any ground unless the wiring was run in pipe or BX.
nate

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<%-name%>
• posted on April 3, 2010, 1:11 am
wrote:

Grounded Romex was introduced about 1947 . It hit the market in a big way in 1950 and was pretty standard by 1954 and the ground was required by code almost universally by 1962.

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<%-name%>
• posted on April 3, 2010, 11:27 am
On 04/02/2010 09:11 PM, snipped-for-privacy@snyder.on.ca wrote:

My own house was built only a year or two before the OP's ('48 or '49) and there isn't a ground to be seen except in the basement where BX was used.
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

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<%-name%>
• posted on April 2, 2010, 9:28 pm

Sounds like a "floating ground"

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<%-name%>
• posted on April 2, 2010, 11:42 pm
I'd suggest to buy a three bulb tester at the store, and see what that reads. Something sounds strange, with that set of readings.
--
Christopher A. Young