Buzzing in the service panel

[jmh21586]

Last night as I was leaving my shop, ready to turn out the lights, I noticed a buzzing sound coming from the service panel.

WTF could it be from??

The only thing I was doing different is I had the interior lights on as well as the exterior lights on. Both on same circuit. First time ever turning the exterior lights on.
When I turned the ext lights off the buzzing went away after a couple seconds.
Anyway, when I got to the house I threw the breaker for the shed just in case. I'll look into it later on today to see if I can recreate the noise and figure it out.


Any ideas??


It's a twenty amp circuit. Three 75 or 100 watt bulbs outside. 18 of the
8' High Output bulbs inside. Thats all that was running.

 

[mrb]

what are the 8ft ho lamps? T8 or T12? Are there nine 2-tub fixtures? or?

 

[jmh21586]

nine 2 tub fixtures for a total of eighteen 8' bulbs.

I'm not sure what type of bulbs.

Got them at home depot if that tells ya anything. I think they are the ones everyone says not to buy.

 

[spongerich]

I'd replace the breaker, there's not a whole lot else in a panel that's likely to make noise.
While you're in there, make sure all of the connections are tight.

 

[jmh21586]

I'm not even sure if it was that circut. But I had nothing else in the shop on, so that's how I came to the conclusion that it was that one. But who knows...

 

[cowboyjosh]

There are a couple of possible causes for this. The buzzing could be either a mechanical vibration or the contacts arcing. This is, unfortunately, one of those problems that someone has to check in person.

The breaker may be on the verge of tripping if the circuit load is always high. Breakers are usually set to trip at about 120% of their rated load or at approximately 18A for a 15A breaker, for example. The contacts on the breaker could have pulled slightly apart and they could be arcing slightly. It is also possible that the bimetallic strip that trips the breaker is vibrating because it is on the verge of tripping. It is not very likely that a breaker would be operating for a long time at the edge of tripping, but you can check by turning off everything attached to that circuit to see if the problem stops.

If there is any faint burning smell near the breaker, it is probably arcing. A breaker that feels slightly warm to the touch is either operating under a heavy load or arcing. A defective or worn breaker may also arc or vibrate. The breaker could also be seated improperly, in which case the buzzing is more of a mechanical problem and isn't too serious of a issue, just re seat the offending breaker.

 

[jmh21586]

Went out today and tried to recreat what was going on last night.
No buzz.

I did reset the breaker last night and maybe that was the trick.

 

[djmartins]

Went out today and tried to recreat what was going on last night.
No buzz.

I did reset the breaker last night and maybe that was the trick.

I had trouble with my heat pump and went to the breaker box and heard buzzing that was the breakers arcing.
Replaced the breakers and everything was good to go.
Might want to replace that breaker next time you are in a HD/Lowes.....

 

[rodm1]

Are mag starter for the compressor buzzes every time it starts. Do you have a mag starter where you here the buzz?

 

[jmh21586]

Nope. Haven't heard the buzz again.