Random light and appliance 'dimming'

[mrgoodkat]

I live in a 30-40 yr old condo, and my lights and appliances seem to 'dim' on a cycle, that occurs randomly, for a random amount of time, and then stops.

With lights, you see a small amount of dimming, that is on a clear cycle. Dim-normal-dim-normal, etc. The dimming occurs for only a second or so. But it appears to only happen with incandescent bulbs. Not the CFL's or the one florescent tube I have over the sink.

With appliances like my fridge and bath exhaust fan, this can be heard, and it the same as described above. The CFL in the housing does not dim.

It doesn't appear to have anything to do with any other appliance being on my unit, or when something kicks on. It also doesn't appear to have to have anything to do with my neighbors, as they have almost all moved out. It is entirely random as far as I can tell. It is happening right now and the only thing on is my laptop. And it can happen with nothing else on at all.

So I have been told about arcing, but this happens in all the other units I have been in. It is complex wide as far as I can tell. Different buildings entirely.

So would this being some I could contact the power company about? And if so, what would I say so they wouldn't automatically write me off?

Aside from being annoying, I have expensive audio/visual equipment, and I'm worried about the strain on their electrical components and power supplies.

thanks so much for your site, and time

[Lightwave]

Intermittent faults are a serious pain to track down. It could be a power company issue. It could be an issue with the wiring, switch gear, and/or transformer that feeds the complex.

I'd take it up with the power company first, but the condo management might need to bring in a very experienced electrical contractor to check out the complex's wiring.

[herrry.james]

It could possibly be the service main has too many circuits on one line...If you can locate your service panel, count a see how many breakers you have. Depending on your apartment size, you should more-than-likely have no less than six, not including the main breaker.

[hj]

The number of breakers is immaterial. What is important is whether the active loads are mostly on one leg of the service feed.

[jadnashua]

It might be worthwhile to pick up a multimeter and use it to see what the voltage actually is. Depending on the speed of the change and how long it lasts, you can probably track it. Some of the multimeters have a fast reacting bar graph in addition to the digital readout that makes transients easier to view.

For your expensive electronics, you may want to run them off of a UPS, which will prevent over and under voltage from affecting them. Some are available (more costly) that have their entire load always powered by the UPS, and the incoming power only charges the batteries. These generally make a true sinewave rather than a stepped or square wave, which is eaiser on electronics.

[andrew79]

A thought i had being as your in a complex is perhaps the original contractor stretched things to the limit....meaning he may have gone over the safe distance for voltage drop. Source voltage will fluctuate and if he's just over the length of a safe run things most likely would work fine most of the time but when the feed voltage dips it would dim your lights or whatever else is on your panel. Florescent lights won't register voltage drops like this....they either have enough voltage to work or they just turn off Unless you have an electronic dimmer or a special ballast designed for dimming purposes.

[mrgoodkat]

Well, thanks for your help, guys.

I called ComEd and got the typical run around. "Everyone else in the complex needs to call us", etc, etc. Much as I expected...

Gut feeling is that it might have actually been the contractor. This would be a vacation condo in Northern Illinois, a town that has always has strong organized crime connections. They used to own property, and vacation up here. Al Capone, etc.

Previous mayors have been outed for their ties. And this particular complex was built by a long out of business contractor, who had organized crime connections.

They are cheap, and the grounds they are on are very nice, right on the lake, but they have their build quality issues. People put up with it because of how cheap they are. So it would not surprise at all if it was something like Andrew79 is describing. We have a lot of unexplained power failures that have nothing to do with weather, and only last a short time, if not a fraction of a second.

Association is even more helpless, so I think it is unfortunately something we will have to live with. Simply chalk it up as just another thing that wont get any attention, in a country where you cannot get anything done correctly anymore. Im only a 30 yr old guy, but I was brought up in an Irish immigrant family, by a father who worked as an electrical contractor for 40 years in the city. I sometimes wish I had grown up in an era where people, and a country, still largely took pride in their work...

Another thought is that they are putting up more buildings on the property (which has been delayed 2 years because of the economy). Maybe this sorts itself out if they start tinkering around with the feed coming into the complex.

Anyhow, thanks guys. Anything changes I will give a shout.