Circuit Breaker (GFI) Suddenly Tripping

Truth71 · Post by **Truth71** » Sun Jul 10, 2022 7:27 pm

Over a year ago I had a dedicated 20 amp line added for the audio room. Code "reguired" a GFI. Worked great, among other benefits lowered noise floor significantly. Last night the breaker blew, twice. This is the first time ever had this happen. Almost 2 months ago swapped out 3-way transmission line box speakers for Maggie 1.7i and DWM, but have not had this happen until last night, so I'm reluctant to attribute to this change?

For those with experience/knowledge: Premature breaker wear? Worse because it's a GFI?

AnotherJohnson · Post by **AnotherJohnson** » Sun Jul 10, 2022 8:30 pm

It is odd for something like this to just “show up” long after a gear change.

If it’s a GFI breaker, you might want to look for a ground issue.

Otherwise it would be due to excessive current draw. Is there a whisker of + speaker wire near a whisker of - speaker wire? I would go back through my speaker connections making sure there were no loose connections, or possibilities of shorts.

None of your gear is protecting itself by blowing its own fuses, so my first thought is the bad ground somewhere idea.

AnotherJohnson · Post by **AnotherJohnson** » Mon Jul 11, 2022 2:38 pm

FWIW, I have owned a lot of houses over the last 44 years, and I’ve seen exactly two failed breakers. So a breaker could fail, but when it fails, I’d expect it to stay failed.

Perhaps there is a less than fully tight ground screw. An electrician on site might be the best troubleshooter.

Post by **admin** » Mon Jul 11, 2022 2:43 pm

I've had GFI outlets and breakers go bad. They are more complex (and thus less reliable) than non-GFI equivalents. If you don't want to buy a new one, you can swap it with another in the breaker box and see if the same behavior exists. BE CAREFUL WORKING ON A BREAKER BOX IF YOU ARE NOT USED TO WORKING ON ELECTRICAL.

The other question I have is why does it need to be a GFI breaker? Those are typically only in places of the house where electric shock would be a concern (bathrooms, kitchen, etc..) I'm not aware of any reason why you would want a GFI breaker for an audio room?

They also tend to flip a lot if there are any electrical motors on the circuit (like fans, etc...).

Truth71 · Post by **Truth71** » Mon Jul 11, 2022 3:20 pm

No ground issues or loose wires that I can see. I’m trying to get an electrician in next week. Interestingly , listened last night with no problems.

Admin- I totally agree with you on the non need for GFI, but the local commissars have safety-itis and have written them into “the code” for ANY new circuit .

AnotherJohnson · Post by **AnotherJohnson** » Mon Jul 11, 2022 3:31 pm

admin wrote: ↑Mon Jul 11, 2022 2:43 pm
The other question I have is why does it need to be a GFI breaker? Those are typically only in places of the house where electric shock would be a concern (bathrooms, kitchen, etc..) I'm not aware of any reason why you would want a GFI breaker for an audio

It is probably an AFCI rather than a GFCI. AFCI is arc fault. GFCI is ground fault.

AFCIs can be required in family rooms, living rooms, bedrooms, etc.

AFCI breakers are for fire prevention rather than electrocution prevention.

Also, if the breakers come by the case from China, they’re not likely to be up to historic QC standards. The two breakers I’ve had fail were both in the Chinese sourced breaker era. If I buy breakers or switches from good electrical supply houses, they’re good. If I buy from big box stores, like Lowes or Home Depot, I have trouble. Especially on the switches.

Truth71 · Post by **Truth71** » Mon Jul 11, 2022 8:29 pm

Another Johnson: Correct, it's an AFCI. Will have electrican check out.

Post by **admin** » Mon Jul 11, 2022 8:51 pm

Ok, AFCI for the room makes sense.

Any chance you have a ceiling fan on in that room?

Truth71 · Post by **Truth71** » Mon Jul 11, 2022 9:41 pm

Nothing should be on the circuit but the duplex receptical for the audio system....BUT....that is one of the things I will have the leectrician check.

AnotherJohnson · Post by **AnotherJohnson** » Mon Jul 11, 2022 11:34 pm

If it is a dedicated 20 amp run, nothing but your gear should be tripping it.

Having the electrician check it out is wise. Something must have arced to trip it unless it is defective. It could be defective, but if it isn’t flipping now, maybe the arc condition was random. If it flipped on starting one item, I’d look to the power switch for that item.

AnotherJohnson · Post by **AnotherJohnson** » Mon Jul 11, 2022 11:37 pm

The fire that an arc fault interrupt is designed to protect against is a simultaneous gas leak and arc. If you don’t have natural or propane gas, it’s overkill. But it is often required by code.

We’ve had arc conditions from failed wall switch contacts, but it doesn’t sound like you’ve got a wall switch on that circuit ( in which case iyou can hear the arc pop when the switch is thrown). Our solution has been to replace the wall switch with an industrial/commercial grade switch.

Truth71 · Post by **Truth71** » Tue Jul 12, 2022 8:46 am

The only propne we have is for a "back-up" generator which is outside the house and more than 50 feet away. LIkewise no wall seicthes thaqt I KNOW of, as it was to be a "dedicated line." But what's behind the breaker in the service box is a mystery that my next electrician ( who seems much more qualified) will check out.

AnotherJohnson · Post by **AnotherJohnson** » Wed Jul 13, 2022 1:57 pm

When we were finishing up our addition, a carpenter moved a big table saw to cut base board and trim. Nearly every time he ran that saw, it flipped the breaker. Of course this is the idea behind admin’s question about the fans. Motors with brushes can, and do, arc.

Here, they finally got an extension cord and ran the saw from a “normal” breaker in the original structures. No trips.

Meanwhile, we’ve not had any trouble with the questionable breaker.

Post by **admin** » Wed Jul 13, 2022 2:01 pm

If that solved the fault, I don't think you have anything to worry about. Not exactly sure what it is about electric motors but those breakers can be finicky with them in my experience.

AnotherJohnson · Post by **AnotherJohnson** » Wed Jul 13, 2022 2:09 pm

They draw huge current on start up, and as they are loaded by cutting.

The motor brushes arc. Brushless motors, which cost more, solve the problem too.

AnotherJohnson · Post by **AnotherJohnson** » Fri Jul 29, 2022 2:57 pm

I hope the OP’s issue has been resolved.

I have enjoyed the P12 power regenerator so much that I’ve been thinking about the P20. And I remembered that the P20 doesn’t really regenerate more than the P12 unless you provide it with a 20 amp circuit.

I wondered how much trouble it would be to add a 20 amp circuit, so I went to the breaker box to see if there were open slots.

Lo and behold, I was greeted with further evidence that I had a good electrician when I built the addition last year.

Every plug in my listening room is on a 20 amp breaker, and it was all inspected and approved by the State Inspector, so the wiring matches the breakers. I could easily accommodate a P20, except for its excessive weight.

Even without a P20, that’s good news for the LP275Ms too. They can ride on one outlet with plenty of current to spare if need be.

Post by **admin** » Fri Jul 29, 2022 5:21 pm

If you are going to add a 20 amp outlet, you basically need to have three criteria for safety:

1) The breaker needs to be rated at 20A
2) The wire needs to be capable and this will depend on the distance to the outlet. This is a good reference article: https://learnmetrics.com/20-amp-wire-size/
3) The outlet needs to be 20A rated.

AnotherJohnson · Post by **AnotherJohnson** » Fri Jul 29, 2022 5:28 pm

The breaker and wire are correct.

The outlet is trivially simple to swap out.

Truth71 · Post by **Truth71** » Sat Jul 30, 2022 10:11 am

"Re: Circuit Breaker (GFI) Suddenly Tripping
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Unread post by AnotherJohnson » Fri Jul 29, 2022 2:57 pm

I hope the OP’s issue has been resolved. "

I haven't had an electrician out yet, but tincture of time has so far proven effective.

Post by **admin** » Sat Jul 30, 2022 2:37 pm

Keep an eye on it. If it does start faulting in the future, I would have that looked at. After all, it's a fire prevention mechanism.