Service Problem

[DonLeffingwellPE]

I was at my brother-in-laws for dinner Sunday night and he told me of a problem he had been having with his lights. He said they keep flickering, sometimes fast, sometimes slow. It doesn't happen all the time, and it seems to be random. And it only happens in part of the house. While I was there, his father and I looked at the service panel. It as a 100 amp-service. The cover was off so I didn't get the make. Both feeds came into the right side top of the panel. His father is a retired electrician. He told me that he had replaced many of the breakers the year before because they were rusty. (??) While we were there that night, he tightened all the connections. I myself pulled on all of the hot wires, to make sure none were loose. We shook our heads and went upstairs. While we were sitting down, sure enough, the lights dimmed and then got very bright. Then they would flicker, and then it just stopped. There has been a lot of new housing in this area.

My own feeling is that the service transformer on the power company side of the system may have some insulation failures in the windings or moisture problems, or both. The local utility doesn't want to be bothered. (I believe the feed to this house is overhead to a weather cap, and then down a conduit).

Any ideas?

Don Leffingwell
dleffingwell@snet.net

 

[REDDOG]

Check with the other houses served by the utility xmer.
If these are experenceing the same problem then it could be utility connections.
If no, then check your service drop and meter socket connections.
Check for loose or open neutral.

This problem could be anywhere in the wiring system.

As for the rust,...is the basement damp, or is the water coming thru the service conduit.
Have fun.

 

[jbartos]

Suggestion: A licensed electrical contractor in cooperation with the Electric Utility is supposed to troubleshoot this problem, perform repair and provide the warranty.

 

[jnims]

It could be a number of things. As a previous poster suggested, I would talk to the neighbors and see if they are having the same problem (make sure their service wires come off of the same transformer). If they notice it also, the transformer or services may be undersized for motor or welder that someone else served from this transformer is using. Another possibility is the neutral conductor is broken or has an extremely poor connection between you and the transformer. This can cause lights to brighten in one part of the house and dim in the other when the load is unbalanced.

 

[HydroChuck]

DonLeffingwellPE,
A number of years ago my beautiful wife was holding the faucet as she stepped into the tub and received a tingling shock. I grabed my meter and measured 40 V from the water to the metal faucet! Further checking showed an imbalance between the two 120 V incoming lines. The 240 appliances operated and measured correct voltage. One of the 120 legs was at 85 V and the other was at 150 V. As I turned things on for one leg and off for the other, I could alter the voltage.
A late evening call to the power company brought two large trucks to my address with lots of blinking yellow lights. They soon confirmed that the neutral in the pad type transformer was lose. After 20 minutes of power company service work to the transformer, the system was normal again. They were not too expressive to give details of how the connection was lose in the first place (legal considerations, perhaps).

 

[wowski]

The cause may be internal or external, if your neighbours are having the same problem then there may be a neutral problem, or overloading of the supply cable/overhead line.
If it is only you that is effected (you say that it only happens in part of the house so this would seem likely) then check all the connections, sockets, lights etc. You can sometimes chase the problem to the source by switching different circuits on and off.
In my experience a lot of times even a small wiring fault can cause this sort of flickering light problem.
The utility may not seem interested if you are the only person to have called in, and they know the supply to your area is adequate. i.e. if a lot of new housing has recently gone in it is likely that they will have re-inforced the area.

 

[DonLeffingwellPE]

Thank you to all who responded. We did get a licensed electrician to look at the panel. The problem was a corroded main breaker, which of course we couldn't see without taking the panel apart.

Don