I recently got a service call that lights were dimming in the home in the evening. They will actually dim like a dimmer switch for 10-20 seconds then go back to normal. They also go out at times. I asked if it was just a certain room, and was told it was all over the home. I check the main breaker and all the neutrals and everthing is tight. The local power company check the pole and weatherhead and said everything is fine. I am meeting with them to have them take out the meter so that we can check the terminals inside to see if anything is loose. I feel the problem is at the post and beyond and the power company should place a meter on this to look for a problem. Anyone got any ideas!!

Have you been able to put a meter on the incoming service while the lights are dimming?

If everything from transformer to main panel checks out all right, maybe it's a problem on thew HV side of the transformer. Does the xfmr feed any other houses, and if so, have they had any problems too?

Some homes are having the same problem but not as often as this one. They all are feeding off the same pole.(about 4 homes)
That is why I am going to request the power company to monitor (meter) the incoming service

It sounds as though it's a problem at the pole, probably somewhere on the secondary splices.

I think the PoCo should investigate.

I agree with you. I meet with them Thursday and will post what the outcome may be. Also I forgot to mention that they are located near a large manufactoring company less than 1/4 mile away. I feel that this may be a possible answer to this problem

very interesting minangelo, recently i went on a similar service call, turns out the poco x-former was shot.

my customer actually got the poco to pay for my serv call!

that was the amazing thing, the poco hates to own up to infastructure inadeqaucies...

let us know how it sugars off

~S~

Did you check the connection between the breaker(s) and the buss bar. Sounds to me like you might be getting some arcing there. I fyou pull the breakers off there will be signs of burnig on the buss if that's the problem. I've also seen a this where the main breaker plugs on before.

Side note — If “hidden” bus connections or breaker internals are suspected, and you have a power-rated voltmeter {UL 61010B-1 cat. III or better} “millivolt-drop” tests can be performed on the suspect energized components. See http://ecmweb.com/ar/electric_testing_contact_quality/index.htm Although the gist of the article deals with magnetic starters, the same concepts can be applied to circuit breakers and bus or cable joints.

Thanks for the info. Will get get back on Thursday with the findings ???????. I feel it is the POCO.

Thursday!

I don’t remember if this was reported on E-C.net or some other board but a weird case of intermittent light-dimming involved a refrigerator/freezer in a remote, dark corner of a new residential garage. The appliance cord was something like a foot short of the wall receptacle, so someone used a wadded-up 100-foot 16/3 extension cord to make up the difference. The refrigerator was not yet used for storing anything—someone figured that it should be powered up just the same.

The compressor would try to start but stall in a locked rotor condtion that would cause excessive voltage drop in the cord—so it could never start, and cycled on the compressor’s thermal overload for weeks. It took that long before the dangeoursly warm cord was discovered.

One of my surplus tool acquisitations was a recording voltmeter for less than $100. It certainly isn't a Draynetz(sp) but can give you a clue as to where to look. I also got a $30 amp clamp for it. It is not unreasonable to make a 24 hr tape. It's nice to have evidence when you want to finger point.

Do any of the neighbors possibly possess heat pump(s) that have a failing compressor or compressor start components?

I did run into this exact situation several years ago, and found that the next door neighbor had a heat pump that was trying to start and locking out. It only happened in the evening, after they got home from work and turned the thermostat up. They didn't really know they had a problem, as the resistance backup was covering the load. I heard the thing groan and snap when I was outside looking at my customers' meterbase.

I have had dimming lights on one leg at my house for a couple of months. I have gone round and round with the power company and was confident that it was not on my side of the meter. I finally got ugly enough that they sent someone that would spend some time.

We loaded up the house - all appliances on.
He added "The Beast" to the service load and found a crimp connection on the pole was getting hot.
The service drop is maybe 6 months old. So all connections were recent.
He remade all connections at the pole and at the weatherhead.

Problem solved.....finally.

The moral of the story is: Maybe it is a crimped connection on the pole. They can look good and still be a problem.

Met with power company on Wedneday and they changed the crimps on the weatherhead. No signs of arcing on the buss bar and the meter was tight. Called the homeowner last evening and the lights are still dimming. I am requesting that the place a tester (meter) on the service.

minangelo,
My $0.02 worth,
If I were trouble-shooting this fault,
I'd be looking at the Step-down Transformer itself, it sounds like there may be an internal connection problem, possibly where the HV or LV connections come through the Bushing on the Transformer body.
BTW, when the lights dim, did you notice any particular noises coming from the pole wiring or the Xformer, like a buzzing sound?.