Troubleshooting residential

[Ramman556]

I’m getting dim lights throughout entire house when anything with a decent load is turned on individually,Toaster , micro wave. Put amp probe on main leg in panel and voltage drops from 117 to around 100 when toaster is turned on . Also amperage goes from 2 to 12 amps.

Any advice is appreciated
Thanks

 

[roger]

Loose neutral.

 

[infinity]

I agree with Roger, loose or lost neutral somewhere. Could be on the branch circuit if it's a MWBC, at the panel, in the meter, at the drop, at the pole or somewhere in between.

 

[roger]

Ramman, please update your profile to show a more precise location.

 

[don_resqcapt19]

What does the voltage on the other leg do? If you have a service neutral problem and one leg drops from 117 to 100, I would expect to see about 134 on the other leg.

 

[Ramman556]

What does the voltage on the other leg do? If you have a service neutral problem and one leg drops from 117 to 100, I would expect to see about 134 on the other leg.

 

[Ramman556]

The other leg stays at 120

 

[Ramman556]

I agree with Roger, loose or lost neutral somewhere. Could be on the branch circuit if it's a MWBC, at the panel, in the meter, at the drop, at the pole or somewhere in between.

Thank you

 

[Ramman556]

I agree with Roger, loose or lost neutral somewhere. Could be on the branch circuit if it's a MWBC, at the panel, in the meter, at the drop, at the pole or somewhere in between.

It’s doing it throughout the whole house. Doesn’t matter what circuit there is a decent load applied to. Lights still dim thru entire house.

 

[Little Bill]

If the 2nd leg is staying the same, it sounds more like there is a problem with the leg that is dropping the voltage.
You should turn off all 2-pole breakers and put a load on one of the legs while measuring line-to-line at the panel. See if the 240V noticeably drops while doing this. Then put the load on the other leg and measure again.
Then with the 2-poles still off, check each leg to neutral with a load on. This will show either one leg bad or show a bad neutral. But with no change in voltage on the other leg, it almost has to be a bad leg.

 

[growler]

I’m getting dim lights throughout entire house when anything with a decent load is turned on individually,Toaster , micro wave. Put amp probe on main leg in the pannel and voltage drops from 117 to around 100 when toaster is turned on .

If you are checking the line voltage at the main breaker (main leg) then you may as well call the power company because the next check would be the meter socket.

 

[andyselec@aol.com]

Usually power company issue. Have them check their connection

 

[Sea Nile]

Sounds like an issue that was described to me by another electrician from work. The issue was one of the conductors between the transformer and the meter can was nicked. When the load was light, it acted fine, but when there was a heavy load the voltage dropped. The power company came out and had to replace the service lateral. But this is all second hand knowledge, so I may be wrong on the details.

 

[ptonsparky]

Sounds like an issue that was described to me by another electrician from work. The issue was one of the conductors between the transformer and the meter can was nicked. When the load was light, it acted fine, but when there was a heavy load the voltage dropped. The power company came out and had to replace the service lateral. But this is all second hand knowledge, so I may be wrong on the details.

Definition of 'nick' is subjective.
SEWAG the nick may have been the start of the problem, but the damage progressed.

 

[Sea Nile]

Definition of 'nick' is subjective.
SEWAG the nick may have been the start of the problem, but the damage progressed.

That's like saying "running over a nail and getting it stuck in your tire may have been the start of the problem, but the damage progressed to a flat tire"

 

[ptonsparky]

That's like saying "running over a nail and getting it stuck in your tire may have been the start of the problem, but the damage progressed to a flat tire"

I've seen plenty of nicked wires. Not a one causing any issues or damage.

Saw enough nails in tires, back when I repaired them for beer money, that were not the reason.

 

[Sea Nile]

Well I'll take your word on it. I was up front and on the level by admitting that what I said was second hand information. Looking forward to and hoping the OP shares the cause once he finds it.

 

[Malywr]

Well I'll take your word on it. I was up front and on the level by admitting that what I said was second hand information. Looking forward to and hoping the OP shares the cause once he finds it.

I had similar situation
Done entire service replace panel
3 days later customer complain some receptacles do not work and some lights

Main breaker OFF. L to L 240v.
L1 to N 120V.
L2 to N. 122V
Main breaker ON load on just all lights
L to L 190v.
L1 to N 120V.
L2 to N 80V.
Utility guy won’t tel me what happened just set at the pol is mess and he repaired connection but needs to be done more work and recommend replacement service cable from pol to house

 

[hillbilly1]

Sounds like it could be a burnt contact on the main, easy to check by doing a fall of potential test. If not there, it may be on the poco side as others have suggested.

 

[kwired]

Well I'll take your word on it. I was up front and on the level by admitting that what I said was second hand information. Looking forward to and hoping the OP shares the cause once he finds it.

Well if OP just has a "nick" in the ungrounded supply conductor that is causing this, based on values mentioned in OP we have an increase in amps of 10 and a drop in volts of 17, so that nick is giving up 170 watts of energy if it is the only thing wrong here. That is a lot of heat in what is likely a pretty small area. More likely for said nick to develop into a bigger problem over time.