Electric circuit breaker corrosion

[Jim Witte]

We've had a problem for the past year or so where every so often one circuit in our house starts to brown-out intermittantly. This circuit is the newest one in the house, and I believe was inserted on it's own breaker. In addition to the brown-outs, evidenced by light flickering as well as phone, TV and VCR turning on and off sometimes (one can hear some relay in the TV clicking repeatedly), a static-like noise can be heard coming from the breaker.

An electrician told us that the problem was corrosion in the breaker or in the wireing in the entire electrical box, which showed up first on the grounding strip. He said that to fix it the entire box would have to be rewired, but that there *wasn't* any risk of an electrical fire.

The odd thing is that it ONLY occurs with this one circuit, and that if all the lights on the circuit (about 260W load) are turned on, the brown-outs will go away in about 10 seconds. If they are turned off, the problem comes back, but if left on for about half and hour, the problem seem to clear up (at least for anywhere between a day to six weeks).

Now for the questions: Why would current flowing through the circuit seem to stabilize it (reverseing the corrosion to some degree, or causing changes in the wire metal which temporarily bypasses the resistance created by the corrosion?) Is there really no risk of electrical fire? Why would it only occur on one circuit, if the entire box had corrosion in it?

Thanks, Jim Witte [e-mail] Indiana University CS

[Michael Lacy]

This does not make sense. If the problem were the breaker, an honest electrician would simply have replaced it, to the tune of say $10 for a breaker and 5 minutes labor. And, the symptoms you describe could be worrisome--- flickering of a light likely means arcing somewhere in the circuit, arcing means heat, and .... And yes, you are correct that problems on one circuit only are not consistent with a problem with the entire box.

My guess for why the problem would improve after a load was on the circuit would be that there is a loose and therefore high resistance connection, which heat sup under load, causing metal parts to expand, and thereby improving the connection until they cool down again. (I can't understand how this would "cure" the problem for weeks, though.)

I would suggest you call another electrician, and sooner, rather than later.

Note--- I am not a pro, just a DIY type who has done a lot of electrical work.

[David Efflandt]

Obviously something is not making good contact. The buzz is something arcing trying to make contact, and higher or prolonged current is heating something up (things expand when hot), completing the circuit. That is NOT good.

Did the electrician actually look at the box and check where the circuit interruption is (why didn't he fix it?), or just guess over the phone? If the latter, how would he know you didn't have an aluminum wire with an unsuitable connector somewhere, which has been known to start fires?

[Jeff Wisnia]

I second Mike's conclusions, it's probably a corrosion/thermal condition, and I'll add:

Check to make sure the circuit isn't wired with aluminum wire. If it is, get some hands-on expert advice.

Your electrician may be suggesting a complete replacement just to make sure that he doesn't get a callback in a couple of months if another circuit starts doing the same thing.

If I were faced with that problem I'd cut the power to the breaker box and pull the suspect breaker out. Look closely to see if there's any signs of arcing (burning) on the blade in the box over which the breaker fits.

If there is, scrape it off and install a NEW breaker, as the female contacts in the breaker probably are also burned and have lost their springiness.

You'd be well advised to wet the breaker box blade with a couple of drops of a conductivity enhancing liquid. I swear by "Stabilant" which happens to be made by a college classmate of mine from nearly 50 years ago. See:

That stuff has worked wonders for me. I used to have problems with the switch blades in the several fused disconnect switches in my home HVAC systems. They would corrode with time and start heating up enough to darken them and the fuse clips and eventually melt the fuse links. Once I cleaned them and put a little Stabilant on the switch blades and the fuse clips I haven't had a bit of trouble.

Even if you don't find corrosion, put in a new breaker anyway, they're cheap enough. And if you do find corrosion, take the time to pull all the other breakers, check them and put a little Stabilant (or similar) on them.

It also wouldn't hurt to check all the screw terminals on the breakers and the neutral and grounding bars with a screwdriver. They can have a tendency to loosen a bit over time.

DISCLAIMER: If you're not knowledgable about how to make sure you've shut offd ALL the power going to the breaker box, leave the job to a professional.

Good Luck and Happy Holidays,

Jeff

-- Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"If you can keep smiling when things go wrong, you've thought of someone to place the blame on."

[Al]

Wait- Before we shoot down the electrician, you should consider this may be a problem with a neutral bar, or a bus bar problem, in which case this WOULD affect the whole problem.

[Jeff Wisnia]

I wasn't sniping at Alex, and after rereading the OP's description of what he was told, I should have used the words "checkout, cleanup and tightening" rather than "complete replacement."

I'm hard pressed to think of a problem with a neutral bar that would affect just one circuit and couldn't be "worked around" by moving that circuit's neutral wire to another spot on the bar. But I suppose anything's possible.

I would agree that if the bus bar had a badly burned breaker connecting blade which was causing the OP's problem, and there were no free slots left in that box to put another breaker on, that would probably justify a total box replacement. The time and trouble required to obtain and install a replacement bus bar, if one could even be found, would outweigh the cost of replacing the whole box. ('Course if it were me, I'd probably spend a couple of hours fabricating and brazing a replacement blade onto the old bus bar. )

The steps I suggested to the OP are equivalent to "rewiring the box"; i.e. checking for connection problems under every breaker and also making sure all wire to breaker and wire to neutral bar connections are socked down tight. I can't think of any other way to "rewire a breaker box" other than replacing every wiring run in the house, which is pretty ridiculous in this instance.

Happy Holidays,

Jeff