3 ms·

I had an AFCI breaker constantly tripping when put under load. I went through and replaced every receptacle in the circuit (everything in the house is nasty st

by cduzz 4y ago

I had an AFCI breaker constantly tripping when put under load. I went through and replaced every receptacle in the circuit (everything in the house is nasty stuff from the 1950s). Still tripped constantly. Opened up every box going back to the breaker, took everything apart, but a test outlet with a test load on each junction and it was "fine" until I put it all back together and started tripping again (replaced the wire nuts, pull tested each junction). Opened up every junction again, replaced every junction with wagos, and no more "nuisance" trips (they were clearly not nuisance trips, though every electrician said "they all do that I just replace the AFCI breaker when the inspector finishes, I'd do that here if you wanted me to fix the nuisance trips here") But of course, I don't pay (money) for my own time... and fixing this wasn't fast.

inferiorhuman 4y ago
Sure, there was an actual problem, but was it a problem that would (eventually) cause a fire? Something something not letting perfection be the enemy of good enough. I think arc fault interrupters are a great idea that's not ready for prime time. I was reading something on a more trades oriented forum where someone asserted that recent updates to the AFCI breakers reduced "nuisance" trips at the expense of actually tripping when there is a legit arc fault. I've no idea how true that is but it's worth noting that GFCIs have been around since the 70s, were worked into the NEC by the 80s, and are comparatively far more mature. AFCI breakers… are not and they have fucking firmware on them that requires periodic updates. With your house I wonder how much was not the wire nuts. Could some of those older receptacles have been contributing to the problems? Without anything more than handwaving and emotion to go on I'd rather see aluminum wiring and back stab receptacles get banned along with some sort of push to get rid of the current installs.
- cduzz 4y ago
  Each step took some part of a weekend; there were typically several months between each step State: 1970s house weirdly full of pre-1970s outlets (probably using whatever the builder could get on the cheap). "Basement" bedrooms have AFCI that trips when using an 8 amp space heater. Circuit breaker is a generic "Fit any panel" model not specifically made for the panel. Outlets wired with a devil-may-care attitude where hot and neutral were both regarded as "makes sparks" and no outlets had grounds. Even though the branch is in a basement area and ends in a bathroom with an outlet right above a sink, there's no GFCI. * replace all the outlets in the circuit, put GFCI outlet on first outlet in the circuit. (still tripped with space heater); GFCI doesn't trip except when tested. * switch circuit to another AFCI circuit; fault follows circuit not circuit * switch back to AFCI, open up boxes between last outlet and breaker and test with a test outlet off each box/junction I can find; can't make it trip; I did reuse the wire nuts; Fixed!) many many months go by * trips under load again * get another AFCI breaker (15 instead of 20A; yes I downsized even though it was tripping -- I didn't think it was tripping from load and I wanted some buffer against the potential there were 14ga wires in the branch) and a bag of wago connectors (for another project). Replaced the breaker -- still randomly tripped but wasn't surprised. (I found an electric supply place only 20 minutes drive away that had the correct siemens breaker style, and finally had free time when they were open!) * open up boxes (again) and replace wire nuts with left-over wago connectors from prior project. That fixed the problem. Now -- the flaky junction was in a steel junction box, but that box was nailed into a rafter against the ceiling. Could it have caught fire? Maybe? It was a 20A circuit, with 12gauge wire. I'll say yeah, it could have started at least smoking if it'd been on a dumb breaker.

by cduzz 4y ago

inferiorhuman 4y ago

Sure, there was an actual problem, but was it a problem that would (eventually) cause a fire? Something something not letting perfection be the enemy of good enough. I think arc fault interrupters are a great idea that's not ready for prime time. I was reading something on a more trades oriented forum where someone asserted that recent updates to the AFCI breakers reduced "nuisance" trips at the expense of actually tripping when there is a legit arc fault. I've no idea how true that is but it's worth noting that GFCIs have been around since the 70s, were worked into the NEC by the 80s, and are comparatively far more mature. AFCI breakers… are not and they have fucking firmware on them that requires periodic updates. With your house I wonder how much was not the wire nuts. Could some of those older receptacles have been contributing to the problems? Without anything more than handwaving and emotion to go on I'd rather see aluminum wiring and back stab receptacles get banned along with some sort of push to get rid of the current installs.

cduzz 4y ago
Each step took some part of a weekend; there were typically several months between each step State: 1970s house weirdly full of pre-1970s outlets (probably using whatever the builder could get on the cheap). "Basement" bedrooms have AFCI that trips when using an 8 amp space heater. Circuit breaker is a generic "Fit any panel" model not specifically made for the panel. Outlets wired with a devil-may-care attitude where hot and neutral were both regarded as "makes sparks" and no outlets had grounds. Even though the branch is in a basement area and ends in a bathroom with an outlet right above a sink, there's no GFCI. * replace all the outlets in the circuit, put GFCI outlet on first outlet in the circuit. (still tripped with space heater); GFCI doesn't trip except when tested. * switch circuit to another AFCI circuit; fault follows circuit not circuit * switch back to AFCI, open up boxes between last outlet and breaker and test with a test outlet off each box/junction I can find; can't make it trip; I did reuse the wire nuts; Fixed!) many many months go by * trips under load again * get another AFCI breaker (15 instead of 20A; yes I downsized even though it was tripping -- I didn't think it was tripping from load and I wanted some buffer against the potential there were 14ga wires in the branch) and a bag of wago connectors (for another project). Replaced the breaker -- still randomly tripped but wasn't surprised. (I found an electric supply place only 20 minutes drive away that had the correct siemens breaker style, and finally had free time when they were open!) * open up boxes (again) and replace wire nuts with left-over wago connectors from prior project. That fixed the problem. Now -- the flaky junction was in a steel junction box, but that box was nailed into a rafter against the ceiling. Could it have caught fire? Maybe? It was a 20A circuit, with 12gauge wire. I'll say yeah, it could have started at least smoking if it'd been on a dumb breaker.