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One of the breakers in my apartment keeps tripping even after resetting. It’s a 15 amp circuit that feeds a bedroom, being used as a home office/recording studio with a laptop, 2nd monitor, a mixer, stereo amplifier, synthesizer, modem, wifi router, printer etc.

It's been running trouble-free for five years, but after a big electrical storm a few days ago, which may or may not be related, that’s when the breaker started to trip once I began plugging back in all the things I had unplugged during the electrical storm.

I tested all devices one by one and found that the amplifier will trip when powered on every single time without fail. I also managed to trip it a few times turning on 2 computers, monitor, the mixer, etc., but this test was hard to repeat.

Just when I thought the amplifier was to blame, I took it around and tested it on different circuits throughout the whole apartment and it NEVER trips any other breakers—whether solo or with other appliances running.

The maintenance guy from the apartment came by, looked at the breaker briefly, reset it, tested the lights in the room and said, "it’s fine" and he still believes it’s my amplifier, not the breaker.

I am not so sure, but I need help ruling things out so I can have some ammo to go back to them and suggest what I believe could be causing it to trip.

Any suggestions on what it could be, what else to look for, or what else to test?

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  • swap 15A breakers – Tony Stewart Sunnyskyguy EE75 Jun 4 '18 at 20:17
  • plug in a high powered hair dryer – jsotola Jun 4 '18 at 20:26
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    A long shot, but doesn't hurt to double-check: Is the breaker that trips a GFCI breaker? And if it is, are the others all NOT GFCI breakers? – manassehkatz Jun 4 '18 at 20:30
  • Was the amp plugged in durring the storm? It sounds like it was unplugged. Just want to make sure. Inverse time breakers rarely fail without a load unless hit with a huge spike and then I would expect other breakers / equipment to have been damaged. If this breaker has been tripped a bunch in the past it may be weak, try swapping with another 15 in the panel to test as others suggest. – Ed Beal Jun 5 '18 at 7:46
  • @manassehkatz - Excellent question. The breaker itself is AFCI; however, none of the outlets on this circuit are using GFCI receptacles. – J2G Jun 5 '18 at 14:09
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Probably the easiest way to determine whether the breaker has gone bad is to swap the breakers between two 15 A circuits. If the problem follows the breaker, then you know it's developed a hair trigger.

Another but more difficult possibility is to plug in something that draws just under 15 A. You didn't specify the line voltage, so I'll pick 117 V. 117 V at 15 A delivers 1.8 kW. If you've got a toaster, space heater, hair dryer, or something rated for 1.5 kW, that might be a good test.

Appliances that put most of the power into a heater would be best to not cloud the issue with large startup currents. Even heaters draw more when cold, but any properly-functioning breaker should be able to ride out the brief surge. If the breaker works fine at just under 15 A continuously but still fails when the stereo is first switched on, then it may not be riding out short surges like it's supposed to.

Your stereo probably has a much larger surge. It sounds like this breaker has developed a hair trigger, and is now more sensitive to short over-current conditions than it should be.

  • I finally convinced the maintenance engineer to come back out and have another look, but he simply wanted to replace the questionable one for expediency, so no definitive cause was identified. He was also of the mindset that it had developed a hair trigger, possibly caused by the storm surge. It's been over a week and all is well. Thanks for the assistance. – J2G Jun 18 '18 at 17:29
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If the amplifier was unplugged during the storm, then I would suspect that a surge damaged the breaker slightly, causing it to trip more quickly on a surge. The surge from turning lights on a few at a time isn't enough to trip it, but the larger surge caused by the amplifier power supply is.

Temporarily swap the wires in the panel between two adjacent 15A breakers. If the problem stays with the breaker, then the breaker is definitely the problem. If the problem stays on the same circuit, then the problem is NOT in the breaker; it's either in the circuit wiring or in the amplifier.


Note that the building code now requires arc-fault circuit breakers in certain areas of a residence, including bedrooms. Unfortunately, these are notorious for nuisance trips, even when not damaged. If this is an AFCB, it's even more likely that a storm surge has made it more sensitive to transients than it should be.

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If you or your maintenance man want to provide any ammo at all, you need to be able to make a reasonable argument. So you need verifiable evidence. You can get that by using an ammeter, preferably one that will give you a high and low reading. So you write down each breaker, its size, test it and the amperage it was reading when it tripped. Also if you have a multimeter you can read the voltage drop across the breaker to see if has unusually high resistance. You can usually buy both meters for about $100.00.

There is no way you can verify without a meter. If you maintenance guy is saying everything is ok then ask him how he is determining it. If he doesn't have any meters then his analysis is mute.

So someone has to test it with meters to get some short of verifiable evidence. It better than looking at each other and shouting "liar liar pants on fire".

  • I'm definitely a numbers guy so this makes obvious sense to me--test the damn thing. I'll see if I can get apartment maintenance guys to go this far in terms of testing or not, but it's quite the logical approach. Thanks. – J2G Jun 5 '18 at 15:03

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