Re: Circuit Breaker Types
The OP mentioned that one particular brand of AFCI had reports of a lot of nuisance tripping.
Originally Posted by MyMilan
Not sure how it is with AFCI, but with GFCI it's a common problem on stages that older guitar amps will trip a GFCI because of stray voltage leakage. In some cases, these amps were just poorly designed -- even when "factory new" they exhibited leakage. In other cases, insulation on some of the components can deteriorate. This isn't really nuisance tripping, as it's really highlighting a problem with the equipment you didn't know was there.
On the other hand, an amplifier that is well-insulated and working properly (no leakage) can trip a GFCI when it is turned on, as the charging of capacitors can result in an imbalance between the legs of the circuit thereby tripping the GFCI. (If the amplifier is constructed with an isolating transformer, this shouldn't happen. Not all are.)
Even with regular breakers, you can have nuisance tripping with certain motor loads. For example, some 1 HP motors -- which have a theoretical running current of about 745 watts, or about 6 amps on a 120V circuit -- can exceed 15 amps at startup (depending on application). An improperly spec'd breaker could trip when this motor starts, especially if there are other loads on the circuit. I have experienced this many times when using my portable power miter saw.
What I wonder about is if an old motor with arcing brushes will trip an AFCI. How about a welder? How about a light switch that arcs when actuated?
My point is that what appears to be nuisance tripping may indeed be an indication of a problem you're not aware of. It may be that the device you are using is designed to have operating parameters outside the operating parameters of the circuit breaker. Before declaring a circuit breaker bad, whether it's a standard breaker, a GFCI, or an AFCI, first eliminate all possible problems and fix them. If you're still tripping, try to identify anything that could be operating normally yet still causing the tripping, and consider a different breaker designed to protect that load without tripping.
Back to MyMilan's post, it would be nice if tools and appliances would be designed properly so they wouldn't cause nuisance tripping of circuit breakers.
And yes, sometimes breakers do go bad. I had a breaker for a water heater go bad; it would randomly trip. Replacing the breaker resolved the issue.
And while I'm sure most everyone who's already posted in this thread knows this, never install a breaker or a fuse with an amp rating greater than what the smallest-gauge wire in the circuit is rated for.
The "Senior Member" designation under my name doesn't mean I know a lot, it just means I talk a lot.I've been a DIYer since I was 12 (thanks, Dad!). I have read several books on various home improvement topics. I do not have any current code books I can refer to. I was an apprentice plumber for two years.