Electrical Outlet Question

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Old 05-04-18, 09:30 AM
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Electrical Outlet Question

First off, I am by no means an electrician, but trying to understand what I am seeing when using a digital multimeter at some of the outlets in my kitchen. First this is an older home and none of the outlets are grounded. Based on that I have replaced many of them with GFCI outlets until I can get this fixed. On one of the GFCI outlets I have my refrigerator plugged in. Recently my wife received a nice jolt from it, but GFCI didn't trip. So did some testing with multi meter and I found that when contacting the metal frame of the fridge with a ground and/or neutral I was seeing 120 volts. So I tested the outlet with a digital multimeter and found the following.

Hot to Neutral: Somewhere around 120V, which I expect
Hot to Ground: 0V, which I expect because I have no ground
Neutral to Ground: 120V, this is very strange to me because there is absolutely nothing connected to the ground on these outlets.

I also visually verified white and black wires are not reversed on this outlet, and the ground has no wire connected or somehow touching hot or neutral wires.

Based on this I replaced the outlet thinking voltage is somehow leaking over to the ground within the outlet itself, and that seemed to help, now seeing 50 volts or so. What is really strange is that number seems to decrease if I remove the outlet from the metal box it is housed in. Note I am seeing the same thing with a kitchen aid appliance on this same outlet. Okay so I then tested some other outlets in the kitchen and finding the same thing with about half the outlets.

I am likely going to call an electrician out, but any advise thoughts ad to what is going on here?
 
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Old 05-04-18, 09:39 AM
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What is the voltage from disconnected hot to the metal junction box?
 
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Old 05-04-18, 09:44 AM
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By disconnected hot do you mean black wire to the metal box the outlet is housed in?
 
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Old 05-04-18, 10:18 AM
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Recently my wife received a nice jolt from it, but GFCI didn't trip.
Some GFI's are not as sensitive to leaking voltage. Good that you changed it. Even with a properly working GFI receptacle you can still get a tingle. Also make sure you use the LINE connections and not the LOAD connections.

Hot to neutral - 120v
Hot to "ground" - 0v
Neutral to "ground" - 120v

That sure looks like the line polarity is incorrect/reversed. When you mention ground.... you need to check to an actual verified ground like the sink.

What type of wiring do you have.... NM cable with no ground.... metal armor like BX ?
 
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Old 05-04-18, 10:59 AM
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Pete,

There is no ground on the outlet here, there is no wire connected to the ground of this outlet. So even if the polarity is reversed how am I able to see 120 volts? I also tested this using the sink as a ground as you suggested. Here were the results.

Hot to "ground/sink" - 120v
Neutral to "ground/sink" - 0v
just for grins Ground to "ground/sink" -120v, what the heck?

Think that is a problem as well.
 
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Old 05-04-18, 11:04 AM
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Cable type is NM, just two wires no ground cable.
 
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Old 05-04-18, 01:39 PM
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black wire to the metal box the outlet is housed in
With the original NM with ground the ground wires were sometimes connected outside the box. Another way to check is open breaker box.and look for any #16 bare wires
 
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Old 05-05-18, 01:23 AM
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You may be seeing ghost voltage, especially when using a digital meter.

Use a low wattage incandescent lamp to "measure" the voltages. If there really is 50V, it would glow a little.
 
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Old 05-07-18, 07:13 AM
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I went and bought an analog multimeter and seeing the same voltages, does that rule out possibility of ghost voltage? I am only seeing between 20 to 30 volts now will that still light an incadescent lamp?

Also have another outlet that is acting up, it flips back and forth on the ground connection. It will normally show 120volts from ground to neutral. Later I can go back and re-test and it shows a good ground connection where hot to ground is 120volts. I can measure this at the surrounding metal box the outlet is contained in as well. I discovered this due to their being a power strip plugged in that indicates when it has a good ground. Sometimes there will be a light indicating a ground and other times it will not be lit Guessing I have a short somewhere on this one to the metal box or the conduit the wire is running in.
 
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Old 05-07-18, 07:25 AM
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A short would be tripping the breakerq. You have a loose connection somewhere in the circuit .
 
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Old 05-07-18, 02:47 PM
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Didn't mean to make you buy a new meter.
And using a clear appliance bulb I can see the filament glow at as low as 12V.
 
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