Weird one

[Fred B]

I wonder if he used a torque screwdriver? To me the torque listed is not near tight enough.

I don't know about that on some. The SD neutral and ground bus screws most times will not take the specified torque without spinning the head. What might be good is if they used the ECX heads instead of the square drive / flat blade combo screw.

 

[sdbob]

So had a service call the other day that overnight lost power on portion of circuit. (Did have storms overnight.) Customer states they had tried to use the shredder in the morning and nothing, assumed the shredder was shot but decided to try a different receptacle, and it worked. He then stated he knew the receptacle had some damage so he decided to replace it. He did the replacement and then the TV on same line stopped working. That is when he called me. First thing was to check the receptacle that he replaced to see if it was wired correctly, connection in correct place. But when I metered first with the circuit tester it showed hot/groung reversed. Put on the volt meter checked Hot-neutral, 6V; hot-ground, 0V; gound-neutral, 116V. Started tracking back toward the origin of circuit next receptacle also showed hot-ground reversed, etc until I got to a good reading. Now he hadn't per his statement changed any other receptacle. Started to open up to see if it had a wire disconnect and make a short that wasn't tripping breaker. Found none, all were wire correctly. Ground-hot did show continuity from the load side at the 4th receptacle but not on line side, so I've isolated the area. Working my way back checking each receptacle for the shorted connection an found none, it did have a gas fireplace that used a connection in between the tested points. Assuming this load had gotten damaged in the storm disconnected it (plug-in unit). Reconnected the everything except the fireplace. Turned on power and retested. All receptacles tested ok, no reversals. Plugged in the power strip for the TV and suddenly got a reversal on the lines again. Unplug the power strip, and still have the reversal. Now really puzzled. Shut off power and re-metered, everything metered correctly between receptacles. So thought could it be power strip, so just plugged in the TV and the cable box (the loads on that circuit) Turned on power and no further reversal. Plugged additional load on line and it still held. So it seems to be related to the power strip.

But the question that puzzling is why did the tester still read as a reversal when I removed the power strip until I turned off breaker and then turn it back on? But if the condition is load related, as that seems to be a more logical situation given the reversal remains until breaker is turned of then reset, does it only present when the loads are applied via the power strip?

Put on the volt meter checked Hot-neutral, 6V; hot-ground, 0V; gound-neutral, 116V
So dropped neutral.

Ground-hot did show continuity from the load side at the 4th receptacle but not on line side
Unclear. Line sides are hooked together on a receptacle. As are neutrals. No line load on ground.

Ditch the receptacle tester.

 

[hillbilly1]

I’ve had neutral bars on GE loadcenters that feel tight, but are not. The threads are not well made, and are hard to turn, so you can’t “feel” whether it is tight or not.

 

[Fred B]

Put on the volt meter checked Hot-neutral, 6V; hot-ground, 0V; gound-neutral, 116V
So dropped neutral.

Not to debate or deny possibility of a dropped neutral, the readings of low voltage on the hot-neutral might suggest that, but to get 0 volt from hot to ground and "normal 116 volts" between the neutral and ground is really puzzling and to me those don't seem like a dropped neutral. Especially the 116 volt between ground and neutral given the ground and neutral are landing on same bus (main service panel).

Also with breaker off checking continuity between the neutral and ground I get only .23 ohm

Ground-hot did show continuity from the load side at the 4th receptacle but not on line side
Unclear. Line sides are hooked together on a receptacle. As are neutrals. No line load on ground.

Refering to the conductors after removing the receptacle, testing line (conductors back to panel) and load (conductors moving away from panel) separately, would think if the neutral dropped at panel the continuity issues would still be present on line side not the load side. So test looked like a short to ground using continuity test somewhere between the 4th receptacle and the 7th. Powerstrip was on the 6th receptacle.
So removed the power strip and that reading remained for about 3 minutes then suddenly disappeared meter then showing OL between hot and ground. That last part also has me scratching my head.
As long as I didn't put the powerstrip back in line none of these anomalies re-presented. Even when putting the loads that were on the powerstrip directly on line without the powerstrip. This would seem like it was the powerstrip that was the cause, but it's the delay in getting "normal" readings after unplugging the powerstrip is getting me.

 

[sdbob]

Not to debate or deny possibility of a dropped neutral, the readings of low voltage on the hot-neutral might suggest that, but to get 0 volt from hot to ground and "normal 116 volts" between the neutral and ground is really puzzling and to me those don't seem like a dropped neutral. Especially the 116 volt between ground and neutral given the ground and neutral are landing on same bus (main service panel).

Also with breaker off checking continuity between the neutral and ground I get only .23 ohm


Refering to the conductors after removing the receptacle, testing line (conductors back to panel) and load (conductors moving away from panel) separately, would think if the neutral dropped at panel the continuity issues would still be present on line side not the load side. So test looked like a short to ground using continuity test somewhere between the 4th receptacle and the 7th. Powerstrip was on the 6th receptacle.
So removed the power strip and that reading remained for about 3 minutes then suddenly disappeared meter then showing OL between hot and ground. That last part also has me scratching my head.
As long as I didn't put the powerstrip back in line none of these anomalies re-presented. Even when putting the loads that were on the powerstrip directly on line without the powerstrip. This would seem like it was the powerstrip that was the cause, but it's the delay in getting "normal" readings after unplugging the powerstrip is getting me.

ok, gimme a min here...

 

[sdbob]

Not to debate or deny possibility of a dropped neutral, the readings of low voltage on the hot-neutral might suggest that, but to get 0 volt from hot to ground and "normal 116 volts" between the neutral and ground is really puzzling and to me those don't seem like a dropped neutral. Especially the 116 volt between ground and neutral given the ground and neutral are landing on same bus (main service panel).

Also with breaker off checking continuity between the neutral and ground I get only .23 ohm


Refering to the conductors after removing the receptacle, testing line (conductors back to panel) and load (conductors moving away from panel) separately, would think if the neutral dropped at panel the continuity issues would still be present on line side not the load side. So test looked like a short to ground using continuity test somewhere between the 4th receptacle and the 7th. Powerstrip was on the 6th receptacle.
So removed the power strip and that reading remained for about 3 minutes then suddenly disappeared meter then showing OL between hot and ground. That last part also has me scratching my head.
As long as I didn't put the powerstrip back in line none of these anomalies re-presented. Even when putting the loads that were on the powerstrip directly on line without the powerstrip. This would seem like it was the powerstrip that was the cause, but it's the delay in getting "normal" readings after unplugging the powerstrip is getting me.

0 volt from hot to ground and "normal 116 volts" between the neutral and ground is really puzzling
I'd assume your neutral and hot are transposed here. Unplug EVERYTHING in the house, including the power strip. Try to grab a reference ground. A wire wrapped around the kitchen faucet stretched to the circuit being tested works. You should read voltage from it to hot, and continuity between it and any HOME RUN neutral.

that reading remained for about 3 minutes then suddenly disappeared meter then showing OL between hot and ground. That last part also has me scratching my head.
While trouble shooting throw out anything you can't duplicate at least once.
You weren't clear. When you re-introduced the power-strip you measured continuity from ground to neutral on the "load" side of the receptacle wiring?

Also while troubleshooting throw out everything the customer tells you as fact. They're clues at best.

So, at the TV receptacle, trace the circuit to the panel. Turn the circuit off. UNPLUG EVERYTHING. Disconnect all wires to the receptacle. If you can separate the ground wires at the receptacle too.Test to confirm you have no voltage to anything at the outlet. Test that you have continuity between 2 wires and only 2 wires. Those will be your ground and neutral. Disconnect the neutral for that circuit in the panel, and disconnect the wire from the breaker. Tie those 2 together in the panel. At the outlet, test that you have continuity between 2 wires and only 2 wires. Those will be your hot and your neutral. This establishes your neutral. In the panel separate the hot and neutral. Leaving the neutral in the panel disconnected, reconnect the hot to the breaker and turn it on. Measured at the outlet you should have voltage between the two wires that aren't your neutral. Turn the breaker off. At the outlet, test for continuity between any 2 wires. You should have none. Test for continuity between your reference ground and all 3 conductors. The wire you read continuity to is your grounding conductor. In the panel re-land the neutral to the neutral buss.

At any point in this linear progression something doesn't read as planned. Stop. You found a problem. Throw out of your mind the assumption that there's only one problem.

Throw out of your mind that grounds are bare, hots are black, and neutrals are white. Anything can be anything, you fix that later.

 

[LarryFine]

As long as I didn't put the powerstrip back in line none of these anomalies re-presented. Even when putting the loads that were on the powerstrip directly on line without the powerstrip. This would seem like it was the powerstrip that was the cause, but it's the delay in getting "normal" readings after unplugging the powerstrip is getting me.

Perhaps it's the act of plugging itself. Are you using the same receptacle with and without the strip?

Have you tried plugging the strip in another receptacle on the same circuit and on another circuit?

Have you pulled the receptacle you've been plugging the strip into and checked the connections?

 

[Fred B]

1 Perhaps it's the act of plugging itself. Are you using the same receptacle with and without the strip?

2 Have you tried plugging the strip in another receptacle on the same circuit and on another circuit?

3 Have you pulled the receptacle you've been plugging the strip into and checked the connections?

1. Am using the same receptacle that I remove the strip from to put the loads back onto. Absent the one load, but I used one of my cords to plug that into the same circuit one receptacle over.
2. No.
3. Yes, one of the first thing I did when I got the anomalous readings. Pulled the receptacles to check for loose or wrong wiring. Only thing of note was on the 4th receptacle that had evidence of a mouse had tried to nest receptacle was pack with fiberglass insulation, carefully checked all the wire for chew damage and found none. Thus my question related to the post #13 whether damaged conductor in the wall could be related to the anomalous readings that come and go. The only thing that messes with this is that cannot replicate without the powerstrip being used.
Loads known on the circuit in issue: 4 lamps, cordless phone base, paper shredder, gas fireplace that has a blower, and the loads plugged into the powerstrip of the TV, cable box and a window AC.

Loads in the section of circuit upstream from the 4th receptacle where the anomalous reading end are the fireplace, the powerstrip loads and the paper shredder and 1 lamp that wasn't plugged in at the time I had arrived or anytime during or after testing.

At first after checking all the receptacles and wiring, getting rid of a back stab situation on one receptacle, put receptacles back into boxes, and on turning power back on and everything looked good no bad readings. Plugged in powerstrip and everything went bad again. That's what started me chasing the anomalous readings.

Just a follow up:
Left powerstrip off the system when I left telling them not to use it, it's a week now and they tell of no more issues with stuff not working. Could it be everything was the powerstrip and the little oddities in the readings are just chasing ghosts that don't exist? Or could there be a problem waiting to get worse?