Voltage present on both hot and grounded terminal of a receptacle.

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skindalooch

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Pennsylvania
Has anyone ever experienced a condition where there is 120V to ground on both the hot and the grounded (neutral) terminal on a duplex receptacle? It's the same potential between the 2 terminals. I had a similar issue years ago and while troubleshooting found it was a faulty GFCI device. This has been ruled out in this case and I have disconnected what I thought was every device in the circuit and cannot pinpoint. Any advise would be greatly appreciated and I understand the vagueness may be an issue. Thanks.
 
Smells like a digital voltmeter is being used and they are notorious about reading a voltage across about anything. You referred to hot and grounded which I am to understand is line and (grounded) neutral and the EGC.

But it is possible that there is an open neutral in that branch upstream and if you have loads attached to that branch circuit down stream they could be back feeding voltage back on the neutral to the point where the neutral is open. As such you would be able to measure most likely 120v from the neutral to the EGC.
I would inspect all of the points where the circuit feeds through to assure that all of the connections are secure.
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skindalooch said:
There is not 240V between the terminals
Click to expand...

So you have 120V L-G, 120V N-G, and 120 V L-N?

You would be unpopular with Kirchhoff.

What are you using to measure the voltage with?

It does seem like something is open somewhere. What resistance is there between N and G at the device? might be just no ground connected there.
 
When energized there is 120 L-G, 120V N-G, 0 L-N. I used a digital multimeter Fluke 38. When the breaker is open the entire circuit is de-energized. The circuit services 1 outside GFCI and 3 bathroom GFCI. I've traced the path of the wire by de-energizing. removing all devices, lifted the branch circuit feeder from the breaker and neutral bar, and used a continuity meter.
 
skindalooch said:
When energized there is 120 L-G, 120V N-G, 0 L-N. I used a digital multimeter Fluke 38. When the breaker is open the entire circuit is de-energized. The circuit services 1 outside GFCI and 3 bathroom GFCI. I've traced the path of the wire by de-energizing. removing all devices, lifted the branch circuit feeder from the breaker and neutral bar, and used a continuity meter.
Click to expand...

Did you have continuity between L-N?
 
skindalooch said:
When energized there is 120 L-G, 120V N-G, 0 L-N. I used a digital multimeter Fluke 38. When the breaker is open the entire circuit is de-energized. The circuit services 1 outside GFCI and 3 bathroom GFCI. I've traced the path of the wire by de-energizing. removing all devices, lifted the branch circuit feeder from the breaker and neutral bar, and used a continuity meter.
Click to expand...

I would start at the breaker and make sure the voltages on the wires are correct there and work my way downstream. Sounds like somewhere along the way some wires got crossed. might be someone miswired one of the GFCIs by swapping an input wire with an output wire.
 
skindalooch said:
When energized there is 120 L-G, 120V N-G, 0 L-N. I used a digital multimeter Fluke 38. When the breaker is open the entire circuit is de-energized. The circuit services 1 outside GFCI and 3 bathroom GFCI. I've traced the path of the wire by de-energizing. removing all devices, lifted the branch circuit feeder from the breaker and neutral bar, and used a continuity meter.
Click to expand...

Sounds like the line and the neutral are both connected to the same 120 volt source. That explains the 120 L-G, the 120 N-G, and the 0 L-N.
 
Carefully check the neutral in the panel. I have seen a break in the neutral where the insulation is still stiff & doesn't give away a broken wire. Remove it from the bar, skin 1/2 inch near the connector & meter it for a break in that span. If good, check neutral in all boxes. Look for any hidden junction boxes or open splices in crawl space, etc. Neutral has been lost somewhere. Check all splices for a wire crept from the wirenut. I have seen that a lot. Splice seems ok but 1 wire creeps out when wire is coiled into the box.
 
skindalooch said:
When energized there is 120 L-G, 120V N-G, 0 L-N. I used a digital multimeter Fluke 38. When the breaker is open the entire circuit is de-energized. The circuit services 1 outside GFCI and 3 bathroom GFCI. I've traced the path of the wire by de-energizing. removing all devices, lifted the branch circuit feeder from the breaker and neutral bar, and used a continuity meter.
Click to expand...
You have an open neutral somewhere between the point being measured and the source. There is also a connected load in the circuit and the fact it is seeking a path back to the source is why voltage is equal on both L and N. Voltage can not drop across a load if the circuit is not complete back to the source. As has been said, you would not be popular with Kirchoff if you don't see this as possible.
 
Funny Timing

Funny Timing

This is one of them "funny timing" moments!

I was just troubleshooting a problem yesterday with some receps not working in a kitchen's countertop.

I first thought GFCI, then the HO said they had a new tiled backsplash installed. So I figured they left the neutral off/loose somewhere as the symptoms of a lost/open neutral were there.

I won't go through the whole process I took in finding it, but it indeed turned out to be a bad GFCI.

The GFCI lost the neutral continuity between the line and load. I don't think I have ever found a GFCI with this problem. It's usually the whole thing going bad in my experience.
I did however, find a bad GFCI once that the line side worked but lost the load side, both hot and neutral.

Anyway, the problem was an open neutral and that fits the OP's description as well.
 
kwired said:
You have an open neutral somewhere between the point being measured and the source. There is also a connected load in the circuit and the fact it is seeking a path back to the source is why voltage is equal on both L and N. Voltage can not drop across a load if the circuit is not complete back to the source. As has been said, you would not be popular with Kirchoff if you don't see this as possible.
Click to expand...


I agree.


A circuit tracer would be the best piece of equipment to use to find this problem. Start at the panel and work your way out. The break in the neutral could be in a buried box or flying splice in a wall or ceiling. Once you check the panel and the first device that's all that's left.
 
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