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Any Issues Using GFCI Breakers for Charging Circuit?

According to the electrician who did my NEMA 14-50 install who has done “countless” other Tesla specific installs in my area, Square D breakers seem to be more tolerant and cause fewer ground faults than any other brand of breaker he had used in an install. So far I have had zero trips while maxing out my mobile connector.
 
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ElectricIAC

Good-Natured Rascal
Dec 31, 2019
6,398
6,765
Tesla Friendly Place
Hi Folks,

Any issues with having their home charging circuit on a 30 or 40 Amp GFCI breaker?

I understand that there are longer charging times on these lower amperage circuits.

I'm still in my planning phase. This circuit/outlet will be in my garage.

Thanks in Advance,
Our 14-50 has an Eaton GFCI box which regularly made the Gen2 UMC lose its ever loving mind: My solution? Buy Gen1 UMC and enjoy 40A charging.

I’m aware this isn’t *ideal* but after giving up trying to find a 14-50 plug HWPC or at least a modified one this was the next best thing. For your setup what’s truly stopping you from just going 50A?
 
According to the electrician who did my NEMA 14-50 install who has done “countless” other Tesla specific installs in my area, Square D breakers seem to be more tolerant and cause fewer ground faults than any other brand of breaker he had used in an install. So far I have had zero trips while maxing out my mobile connector.

Now that it's been 9 months do you still have no issues with tripping?
 
Hi Folks,

Any issues with having their home charging circuit on a 30 or 40 Amp GFCI breaker?

I understand that there are longer charging times on these lower amperage circuits.

I'm still in my planning phase. This circuit/outlet will be in my garage.

Thanks in Advance,

I have a 240V / 50A line (shared between the unused outdoor hot tub and beloved 14-50 in the garage) on a GFCI. Never an issue...
 
  • Funny
Reactions: ElectricIAC
The 2017 NEC is generally interpreted to REQUIRE GFCI on EVSE circuits, so no, it’s not an issue.
If you are hard-wiring a wall connector, the GFCI is present in the unit, and as such the instructions state that there should not be a GFCI breaker on the circuit, as multiple GFCIs can cause unexpected trips, as some have reported here.

A prior resident of a friend's home had a 14-50 plug installed outdoors for mobile charging, which did require a GFCI to pass inspection, but then swapped in a non-GFCI breaker to avoid that issue. She then used that outlet and a 50A cable (normally used for electric stoves, presumably) to hook up her wall connector, and hasn't had any issues. As I don't have 240V available at home, I'm quite grateful for this :)
 

ucmndd

Well-Known Member
Mar 10, 2016
10,171
19,994
California
If you are hard-wiring a wall connector, the GFCI is present in the unit, and as such the instructions state that there should not be a GFCI breaker on the circuit, as multiple GFCIs can cause unexpected trips, as some have reported here.
Yes, I agree. I think my statement is still accurate but your clarification is good - 2017 NEC requires GFCI on circuits intended for EV charging. Whether that's provided internally by a hard-wired EVSE or via a GFCI breaker on a circuit with a receptacle is immaterial, but you probably don't want both.
 

Rocky_H

Well-Known Member
Feb 19, 2015
8,794
11,471
Boise, ID
Yes, I agree. I think my statement is still accurate but your clarification is good - 2017 NEC requires GFCI on circuits intended for EV charging.
No, that's not true. (I just noticed I accidentally gave an informative mark on your comment from before, when it wasn't accurate.)
It is not for CIRCUITS used for EV charging. It is very specific in that it states for RECEPTACLES being installed for EV charging. Hard wired devices are excluded from that GFCI breaker requirement completely.

And for people trying to explain it by saying it is because the wall connector has a GFCI built into it, no, that's not the reason, because the mobile connector cable does too. They are the same in that way. The real difference is in how they are physically used. People will be holding a plug with exposed prongs in their hands to push it into a receptacle. There is some potential for shock there. With hard wired units, the wires are hidden, not exposed, and not being handled by people as they use the device, so it doesn't have the shock risk that a plug in device does.
 

ucmndd

Well-Known Member
Mar 10, 2016
10,171
19,994
California
No, that's not true. (I just noticed I accidentally gave an informative mark on your comment from before, when it wasn't accurate.)
It is not for CIRCUITS used for EV charging. It is very specific in that it states for RECEPTACLES being installed for EV charging. Hard wired devices are excluded from that GFCI breaker requirement completely.
Point taken and fair enough - although in practice I'm guessing the difference is immaterial as I don't imagine there's a hard-wired EVSE on the market without built-in GFCI.
 

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