Breaker buzzing

[igor]

I'm a real estate inspector and come across situations every so often where an individual breaker buzzes faintly or has a noticeable buzz from a distance. None of the other breakers in the panel buzz. The panel manufacturers vary (not just FPE or Zinsco). I always recommend further evaluation by a licensed electrician since we do not do any diagnostics.

Would buzzing be attributed to current through the ground without trip response by the breaker? Is any level of audible buzzing at a breaker a red flag requiring further evaluation?

 

[bphgravity]

Re: Breaker buzzing

I have been told that breakers hum because they don't know the words to the song.

Actually, breakers have moving internal parts that can and do wear out over time and sometimes are "bad" directly off the manufacturing line. In some cases, it can be a sign of poor breaker to bus connection or could also be a sign of slightly excessive current being used.

I have had occasions were simply turing the breaker off and back on or by moving the breaker to another bus location cleared the problem. I suppose in all cases it would be best to have a licensed and insured electrician evaluate and also make corrections if need be.

 

[templdl]

Re: Breaker buzzing

No, breakers are not necessarily "bad" if they buzz. Since a breaker consists of many parts, many of which are made of steel , and alternating current does set up an alternating magnetic field around the conducting path by which it flows through, it can cause this item to start to vibrate if they are loose. Common items which can cause this are washers used as spacers or a plate of in an arc chute assembly which is not staked in space adequately.
If the breaker is not hot to the touch and opens and closes without incident the "buzz" if only a nuisance. Remember, that without actually testing the breaker one can not assume that it will not protect. Other that getting rid of the buzzing sound there is no assurance that a replacement breaker will be any better at protection than the one that buzzes or hums.
Also remember that both noise and warmth are relative, that is noise can be compared to the ambient noise. In a very quiet are a hum of buzz may seem quite load where it may not be heard at all in areas where is more ambient noise.
As a side note when someone expects something to be cool to the touch but it's warm it is common to say that it is hot. Breaker are allowed to get quite warm if they are loaded as there do have a wattage loss which is often a consideration by consultants when sizing A/C for electrical rooms.