AFCI Tripping on Lighting Circuit

[Burbman]

UPDATE: AFCI Tripping on Lighting Circuit

So all the lights in my 24x30 garage are on one circuit, fed by a 15a AFCI breaker in the garage subpanel. This is a brand new garage built about a year ago and a new 100a subpanel installed.

This circuit includes the four 6-bulb t8 fluorescents in the main part of the garage, two 4' shop lights over the workbench, a motion-activated LED fixture outside each of the two service doors, and a motion-activated spotlight over the garage door. The exterior lights are direct wired, the inside fluorescents are wired with cords that plug into outlets. The outlets are single-receptacle and only there as a means to disconnect the fixtures should I need to bring one down to change a ballast. There are NO outlets on this circuit that you can plug anything into like tools, etc..

All was fine until about 2 months ago, now the AFCI breaker is starting to trip at random. It trips about once per week now.

The big fluorescents are these: https://www.prolighting.com/catalogsearch/result/?q=b4146t81mht0000

I have heard that electronic ballasts in these lights can create issues with AFCI breakers. I'm wondering if I should replace the AFCI breaker with a regular one?

 

[ddawg16]

I have AFCI's in my house and the only time it tripped was when I had a broken wire....it was doing what it was supposed to do.

How old is your AFCI?

Have you tried disconnecting one light at a time and seeing if it still trips?

Have you tried swapping out the AFCI with a regular breaker? (for troubleshooting reasons only)

If it was me, I'd turn on the lights and start banging on the lights and fixtures. If you have a loose wire, this might illuminate it's location. (pun intended)

 

[Burbman]

This whole install was done in Jan of 2017, so almost a year old. The infrequent occurrence makes me reluctant to operate with one or more fixtures offline.

 

[Norcal]

Attached or detached garage?

 

[Burbman]

Detached with 100a subpanel

 

[Bert_]

I hate afci's with a passion. I've had brand new dishwashers, refrigerators, vacuums, some electronics trip them randomly. Usually just switching out the breaker, with another AFCI, will solve the problem. But I've put in regular breakers if, after a close inspection of the circuit, the problem persists. Power tools will trip them every time.

If this is a detached shop I'm surprised you were required to install AFCI's.

 

[Norcal]

According to the Mike Holt website, NY is is on the 2014 NEC, which has no requirements for AFCI's in garages either attached or detached, the 2014 NEC added kitchens, & laundry to the AFCI list but not garages. since it's not required, replacing the AFCI with a circuit breaker is fine. GFCI protection is more important & required for garage receptacles.

 

[Burbman]

Yeah, I didn't have a good experience with this electrician. Instead of using my guy, I let the contractor bring in his guy....big mistake....He originally installed a 20 amp AFCI breaker on a circuit fed with 100% #14 wire (I changed it out for a 15a AFCI). When the "inspector" came, it actually passed, but he never took the cover off of the subpanel, never looked at the trench (since it was already filled in) and never went into the basement to see how the wire was run and how it tied into the main panel. Then the inspection company wouldn't release the cert to me so I could get the CO, since apparently I was the last job the electrician did before he closed up and went out of business. I had to pay the $175 inspection fee to get then to release the cert to me.

I am leaning towards just installing a regular breaker if the code allows, rather than waste time trying to diagnose a problem that may not even exist.

 

[cybrdyke]

I'm not certain how it would affect an AFCI breaker, but it's well known that leakage current from electronic ballasts play havoc with GFCI breakers. Just a heads up if you intend to swap the AFCI to a GFCI.
Good luck,
CD

 

[ddawg16]

I hate afci's with a passion. I've had brand new dishwashers, refrigerators, vacuums, some electronics trip them randomly. Usually just switching out the breaker, with another AFCI, will solve the problem. But I've put in regular breakers if, after a close inspection of the circuit, the problem persists. Power tools will trip them every time.

If this is a detached shop I'm surprised you were required to install AFCI's.

I've ran just about every power tool I have off one of my AFCI's and never had a trip.

I do have a heat gun that will trip one of my garage GFCI's. If I move that heat gun to the last outlet on the string, it doesn't trip. But that same heat gun did not trip the AFCI.

But....one of my required AFCI's did trip when I had a broken wire in a box.

 

[Burbman]

Went out to the garage last night to turn off the lights and....they were already off. Breaker had tripped again. Frequency of trips is increasing to every other day, not sure if I have a wiring problem that's getting worse or the breaker is failing.

 

[Burbman]

UPDATE: This is a Bryant AFCI and it has 2 LEDs that indicate the trip reason when it trips.

It looks like it's tripping for "Arc Fault or PTT Passed"...I guess that means it is detecting an arc somewhere. It's definitely the fluorescent lights because the breaker doesn't trip with them off.

I calculated that max potential draw on the circuit is about 9a, so it shouldn't be overloaded.

 

[cybrdyke]

Could be a small arc in one of the fluorescent sockets. Might not be big enough to be a problem, but just big enough to trip your AFCI. Look for a lamp that has a blackened end as a likely culprit.
CD

 

[fastjohnny]

Had a 15A GE AFCI on a lighting circuit tripping more frequently, then finally wouldn't reset. Today, I replaced with a new AFCI to test, and no more tripping.

 

[ddawg16]

Do you have more than one AFCI? If so, swap breakers

 

[nomadskidoo]

Fun of contractors!Bid @$4k done @$8k kinda normal guys!Thanks to general