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Wall Charger Tripping AFCI's on Other Circuits

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This is an interesting issue.. i wonder if the chargers are lacking noise suppression and the afci breakers are seeing that noise as as an arc...

Here is an approximation of what an afci sees under fault conditions.

upload_2019-12-5_19-27-24.jpeg


So, i’m not sure what is in the wall chargers but i there is some sort beefy capacitor in there it could generate some kinda noise while the capacitor charges....

Another view....

upload_2019-12-5_19-30-0.jpeg


upload_2019-12-5_19-30-0.jpeg

Arc Detection with the AFCI - IAEI News magazine
 
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I’ve had the same issue. Mine was not actually the car charging itself it was caused when my car was charging and the refrigerator kicked on or the Hairdryer. Went and checked those neutrals at both the panel and receptacles, ended up being the receptacle creating an arc condition exasperated by a slightly lower voltage replaced and problem solved.

Does it trip everything when just powering on or when plugging the car in? In other words is it immediately or delayed?
 
Sounds like bad AFCI/GFCI breakers to be honest. I had similar problems in my new construction house (pre-Tesla) on two specific circuits until the electrician replaced the breakers. He said his company has seen the problem quite often and that its normally an overly sensitive breaker.

This ^^^^^^^^^^

It is very unlikely that this is a Tesla issue. I agree with the comment that electricians miss things. I am a bit frightened that the OP appeared to be working on some of this stuff himself? Yikes. No matter what you tweak in this world, if it's done incorrectly it can lead to seemingly unrelated issues.
 
I have been watching this thread with interest but have not chimed in as I did not have any clear advice.

So tripping AFCI on an unrelated circuit is really weird. I am thinking there are a few ways that the Tesla could influence this:

1. As the Tesla ramps up charging it may be pulling the voltage down on your service over all. There may be some condition on that AFCI branch circuit that was very close to tripping the circuit but it did not quite do it. Once the voltage is dragged down enough it may put it over that threshold. (AFCI trip mechanisms are complicated and driven by a microprocessor)
2. The Tesla may be creating some kind of noise or harmonic on the electrical service that again is pushing the AFCI over some limit. This would be really hard to troubleshoot without advanced tools and skills. We have seen Tesla’s trip some GFCI breakers, perhaps for similar reasons.
3. AFCI’s also I believe have some basic ground fault circuitry in them. This is more of a long shot, but if there was some really weird leakage of current from the Tesla circuit into the AFCI circuit (to like nicked wires that are touching in the same conduit) it could cause an issue like this. But that is such a long shot I don’t even think I should have mentioned it.

My first course of action here would be to look at the voltage when you first plug the car in (immediately before charging starts) and then compare that to the voltage after the car fully ramps up and has been charging for a minute or so. If that drop is excessively high that could indicate other issues.

Next, I would troubleshoot the circuit in question. There are two paths you could start with:

1. Replace the breaker with a new one. The newer models may be a little less sensitive than the old ones (I would check if your current breaker is still sold or if it has been superseded by a new one). This by itself could solve it if your breaker is bad or just the old model is overly sensitive.

2. The other thing to do is to try to track down a device on the circuit that may be causing it. Catalog every receptacle/light/device on the circuit and disconnect/turn things off and see if the issue occurs. It could be a bad device that has a legit frayed cord and is causing arcing, or it could just be a device that always causes nuisance trips (that is not otherwise malfunctioning). If is not obviously isolated to one device, then you may need to tear into every single receptacle/switch box/junction box and make sure all the wires are right and not touching each other. I recently upgraded my in-laws to some a AFCI breakers and they were having nuisance trips when running relatively high current loads on the circuit (but not isolated to a single device). I found a receptacle where the bare ground wire was touching the neutral screw. So this had probably been that way for decades. Some current was returning to the transformer via the ground path rather than via the neutral. This was causing trips on the AFCI breaker since it also has some
GFCI like functionality.

I know this sucks, but these issues can be very difficult to troubleshoot. I do find is extremely odd that the Tesla causes nuisance trips on unrelated 120v circuits! Not good!

Please do report back on any resolution or new learnings!
 
I've done a lot of charging over the last few days and no issues to report at all. Pretty confident it was just an out of spec AFCI breaker giving me the trouble. Hopefully this can help others if they run across this odd issue in the future.
I’m in a newer home and having AFCI issues on other circuits. Still no issue after switching out breakers?

Thought about buying a Gen 1 mobile connector to see if that helps.

I’m having random circuits tripping while my Tesla charges. Looking for any help.
Electricians are bleeding me dry haha.
 
I have a model Y and my home was built in 2020. I have the Tesla wall charger (2nd Gen). I have the same issue as mentioned above. I have a 50amp breaker on the wall charger and I have set the wall charger at 9 (40amps). After few mins of charging, a whole bunch of other AFCIs get tripped. The electrician who did the electrical work for my entire house looked at it and is asking to change all the breakers to GFCI since he tried replacing the new AFCIs and they had the same issue. Any resolution will be greatly appreciated.

thanks
 

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I have a model Y and my home was built in 2020. I have the Tesla wall charger (2nd Gen). I have the same issue as mentioned above. I have a 50amp breaker on the wall charger and I have set the wall charger at 9 (40amps). After few mins of charging, a whole bunch of other AFCIs get tripped. The electrician who did the electrical work for my entire house looked at it and is asking to change all the breakers to GFCI since he tried replacing the new AFCIs and they had the same issue. Any resolution will be greatly appreciated.

thanks

I have an idea:

AFCI breakers have electronics in them that can detect arcing within a circuit (typically caused by a loose connection). I am wondering if you have a loose connection somewhere on the main feeds to your panel, in the meter base, or even more likely, outside the home between your house and the utility transformer nearby.

As the Wall Connector ramps up it pulls enough current to trigger this arcing condition which each of the AFCI breakers notice and properly trip.

I don't know that those breakers can tell the difference between an arc happening within the circuit vs. upstream of the circuit.

Did you ever come to a resolution on this?
 
i have a similar issue...
not sure if mine are GFCI or combo
i added a 100amp breaker for Gen2 80amp WC
everything works fine unless i'm using some other heavy draw in the house

one day car was charging at 72amp n i turned on the espresso machine in the kitchen n 20A GFCI breaker tripped n wouldn't reset
i thought it was broken, got new one but when i disconnected tripped one it reset. put it back n week later same story
put coffee machine on diff circuit n week later had this 2nd 20A kitchen breaker pop, although this one resets ok every time
so, now i'm thinking that somehow WC causing other GFCIs to pop but only under somewhat heavy load (1kW coffee machine)...
everything works fine when its not charging or any lights etc are used
house is built in 2018 n no issues till i started using WC...

For electricians here, does placement order of regular vs GFCI breakers matter??
i noticed that all my regular ones are at the top...

1671311910620.png


1671312049012.png
 
i have a similar issue...
not sure if mine are GFCI or combo
i added a 100amp breaker for Gen2 80amp WC
everything works fine unless i'm using some other heavy draw in the house

one day car was charging at 72amp n i turned on the espresso machine in the kitchen n 20A GFCI breaker tripped n wouldn't reset
i thought it was broken, got new one but when i disconnected tripped one it reset. put it back n week later same story
put coffee machine on diff circuit n week later had this 2nd 20A kitchen breaker pop, although this one resets ok every time
so, now i'm thinking that somehow WC causing other GFCIs to pop but only under somewhat heavy load (1kW coffee machine)...
everything works fine when its not charging or any lights etc are used
house is built in 2018 n no issues till i started using WC...

For electricians here, does placement order of regular vs GFCI breakers matter??
i noticed that all my regular ones are at the top...

View attachment 886145

View attachment 886146

It doesn’t matter, but if the tripped breaker were close to the 100amp breaker for the evse you might wonder if the heat generated by the evse breaker is preloading your 20 amp breaker with heat and when the additional load is applied the temperature rises above the trip threshold.

Is the the same breaker tripping both times?
 
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It doesn’t matter, but if the tripped breaker were close to the 100amp breaker for the evse you might wonder if the heat generated by the evse breaker is preloading your 20 amp breaker with heat and when the additional load is applied the temperature rises above the trip threshold.

Is the the same breaker tripping both times?
its #14, 3 up from 100amp breaker so don't think its that..
first 2 times #14 tripped n wouldn't reset
then #12 (2nd kitchen circuit) twice but reset every time

actually fast forward, 2 days ago my bedroom one tripped, #15
it was during ramp up when i started the charge n both kids were gaming on PCs, so 500W power supplies in those plus monitors
so my guess it was pulling around 1kW...

It seems that any circuit that has heavier load trips, at least during charging start... Noise maybe as others said? or sensitive breakers??
 
Breakers go bad. AFCI and GFCI go bad more often because there is more junk in them to go bad.
that might be true in general n it is true for my first one that won't reset but 3 separate ones tripping randomly is too much of a coincident
so i vote that its either sensitive breakers (designed without EV chargers in mind) or noisy charger (maybe just nature of WC?..)
i'll do more testing with new breaker n update here.
 
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Reactions: NevG
so i vote that its either sensitive breakers (designed without EV chargers in mind) or noisy charger (maybe just nature of WC?..)
i'll do more testing with new breaker n update here.
The WC really doesn't do anything while your car is charging, it just has big contactors/relays that connect the power straight to the car, where the actual charger exists.
 
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The WC really doesn't do anything while your car is charging, it just has big contactors/relays that connect the power straight to the car, where the actual charger exists.
i understand that, but i believe i've read somewhere on here that WC/UMCs do some test or ping to ground...
bottom line is something has to fluctuate either on power line or ground to set off the breaker only while charger is running...
 
  • Disagree
Reactions: NevG
i understand that, but i believe i've read somewhere on here that WC/UMCs do some test or ping to ground...
bottom line is something has to fluctuate either on power line or ground to set off the breaker only while charger is running...
Correct, the WC tests the ground connection, and AFCI and GFCI breakers interpret that as a fault.

Your breakers are the problem.
 
This is an interesting issue.. i wonder if the chargers are lacking noise suppression and the afci breakers are seeing that noise as as an arc...

Here is an approximation of what an afci sees under fault conditions.

View attachment 485159

So, i’m not sure what is in the wall chargers but i there is some sort beefy capacitor in there it could generate some kinda noise while the capacitor charges....

Another view....

View attachment 485160

View attachment 485160

Arc Detection with the AFCI - IAEI News magazine
I had the same problem brand new GFCI breaker kept popping. I replaced it with the old non GFCI so far so good.
I’m using a 240 volt 30 amp with a portable charger