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GFCI Breaker is Code for EV Charging

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In preparation for getting our MY we had an electrician install a NEMA 14-50 outlet on a dedicated 50A breaker in our sub-panel. We didn't want to pay a Tesla tax, so we said it was for a family member's RV (which is true) and that we hoped to use it for a future electric vehicle (also true). Today we had the county inspection and we were told that the new code for EV charging requires a GFCI breaker and he signed off on it only for use for the RV. Had I known, I would have had the electrician install a GFCI breaker as I definitely want to be following code and I do think we should have been advised of the new requirement by the electrician. That said, we passed inspection and we have our charging outlet. Should we change it? It is in an enclosed garage and it is hard to imagine that there is any real risk here. Has anyone had issues with a GFCI breaker tripping without cause? I think the company that did the install will correct it upon request, with minimal additional charges. I also have a family member who can do it the next time they visit. Any experience or advice in regards to GFCI breakers for EV charging? Should I correct this, or just use it as is?
I put a 60amp line in and no GFCI BREAKER. GFCI breakers would be appropriate for an RV because of appliance and moisture proximity.
GFCI breakers respond to spikes in amperage, like dropping you electric saw in your wife’s bath. My understanding is a hand shake takes place between the charger sensor and the EV cpu and that charging is a gradual process. Wait till you get the EV.
 
I put a 60amp line in and no GFCI BREAKER. GFCI breakers would be appropriate for an RV because of appliance and moisture proximity.
GFCI breakers respond to spikes in amperage, like dropping you electric saw in your wife’s bath. My understanding is a hand shake takes place between the charger sensor and the EV cpu and that charging is a gradual process. Wait till you get the EV.
If you installed a 240V/60 amp circuit it would be for the Wall Connector or other hard wired EVSE. A GFCI circuit breaker is NOT required for a hard-wired installation.
 
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I put a 60amp line in and no GFCI BREAKER. GFCI breakers would be appropriate for an RV because of appliance and moisture proximity.
GFCI breakers respond to spikes in amperage, like dropping you electric saw in your wife’s bath. My understanding is a hand shake takes place between the charger sensor and the EV cpu and that charging is a gradual process. Wait till you get the EV.
Incorrect - GFCIs respond to current differentials between the wires. They do not respond to spikes and are not over current protection devices like a circuit breaker or a fuse.
 
Incorrect - GFCIs respond to current differentials between the wires. They do not respond to spikes and are not over current protection devices like a circuit breaker or a fuse.
Exactly. It is looking for current that doesn't return on the neutral (for 120v) or other hot line in the case of 240v. This would be the case if, for instance, a person touched one of the hot wires and current tried to follow through their body to ground.
 
Doesn't the Tesla mobile charger have built-in GFI protection? I know the HPWC does. No experience with it but I have always been under the impression that it's not recommended to follow one GFI with another, as they can trip unnecessarily. Is this true?
I don't think the mobile connector is GFCI protected. Even if it was, it wouldn't cover the bigger risk - the long prongs on a 14-50 are easy to touch when partially plugged in.
 
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Doesn't the Tesla mobile charger have built-in GFI protection? I know the HPWC does. No experience with it but I have always been under the impression that it's not recommended to follow one GFI with another, as they can trip unnecessarily. Is this true?
To my knowledge it doesn’t. I’ve never seen anything stating it does, either.

GFCIs in series shouldn’t be an issue but they’re unnecessary. As @MY-Y said, the bigger risk is with at the plug. Even if the mobile connector has GFCI protection it won’t protect you from issues upstream.
 
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Doesn't the Tesla mobile charger have built-in GFI protection? I know the HPWC does. No experience with it but I have always been under the impression that it's not recommended to follow one GFI with another, as they can trip unnecessarily. Is this true?
All EVSE have built-in GFCI protection. The EVSE GFCI is designed to protect the user when plugging and unplugging the charging connector into the charging port of the vehicle. Adding GFCI protection for the receptacle, accomplished either by installing a GFCI receptacle or installing a GFCI circuit breaker, protects the user when plugging and unplugging the EVSE power plug from the power source. (You could turn off the circuit breaker prior to plugging or unplugging the EVSE from the power source, especially recommended whenever plugging or unplugging an EVSE into a 240V circuit, and accomplish the same level of protection as the GFCI receptacle for the user handling the power plug.) When the EVSE is hard wired, as with the Wall Connector there is no power receptacle, no need for a GFCI circuit breaker.
 
I'm coming in very late to this thread. I've read the first page and last page and I haven't seen anyone mention the user manual for the Gen 2 Mobile Connector, which I think is a good source for answering the question of whether that EV connector has GFCI protection. Surprisingy, there is no direct answer to that question in the manual, But in the section where it talks about "Status Lights", you can find the following:

Green light OFF with Red light showing 1 Flash, indicates: "Ground Fault. Electrical current is leaking through a potentially unsafe path."

That sounds to me like built in GFCI protection, which agrees with many answers in this thread.

The other part of the original question is this: What happens if I put a GFCI breaker in the panel and then plug a GFCI protected Mobile Connector into that GFCI protected outlet to charge my EV? In my experience and based on verbal answers from an experienced electrician who has installed many EV circuits: When you have two GFCI devices on the same circuit, it may work briefly, but then one of the GFCI breakers will trip and shut off the circuit. His advice to me (for installing an outlet for EV charging) was that you should install a GFCI breaker in the panel just to pass inspection, but then take the GFCI breaker out and put a standard breaker in the panel.

There have been a number of responses that address the issue of a potential shock hazard when plugging in or unplugging the Mobile connector to/from the outlet. That appears to be a valid concern, but I don't see a solution to that concern other than to not touch the prongs of the plug. I, personally, have sufficient respect for and maybe even fear of 240V electric circuits that I don't consider that a real threat.

To find the user manual for the Get 2 Mobile connector from Tesla.com home page try this:

Move cursor onto: Charging
Click on: Home Charging Learn
Scroll down a little and click on: Compare Products
Scroll to the bottom to "Additional Resources" and click on: Installation Manuals and Product Guides
Under "Owners Manuals" click on: Owners Manual Gen 2 Mobile Connector
Click on: North America
Click on: English
Scroll down to page 12 and look for "Green light OFF, Red light 1 Flash"
 
Doesn't the Tesla mobile charger have built-in GFI protection? I know the HPWC does. No experience with it but I have always been under the impression that it's not recommended to follow one GFI with another, as they can trip unnecessarily. Is this true?
Longer reply below, but the short answer is: Yes it is internally GFCI protected, and yes if you put two GFCIs in series on a single circuit, one of the GFCIs will trip.

I'm no expert either but I think your answer is the most direct and the most correct answer I've read in this thread (I only read the first and sixth pages).
 
The NEC now specifies that a GFCI is required for new residential electrical circuits used for EV charging where the circuit terminates at a receptacle and the electric vehicle service/supply equipment (EVSE) is fitted with a power cord and a plug. Currently GFCI protection is not required for hard wired installation of the EVSE. The GFCI at the breaker or at the receptacle is there to protect the user when plugging or unplugging the EVSE from the receptacle.

This risk has always been present, not addressed until this code update. The owner's manual for Level 2 EVSE typically include a warning to always turn off the power at the panel before plugging or unplugging the EVSE from the receptacle. This is especially important for 240V receptacles, i.e. 14-50 receptacles. (Note: 14-50 receptacles used for kitchen appliances and for powering RVs do not require GFCI. (An RV motorhome's electrical system is a distribution panel, not electrical equipment (the GFCI is not compatible with an RV.)

In the future GFCI will be required for all outdoor electrical equipment (even if hard wired.) This will apply to home air conditioner compressors which are currently not compatible with GFCI (a child was electrocuted, died while stepping over a backyard fence onto an AC compressor housing that was energized.) This will apply to outdoor installations of hard wired EVSE such as the Tesla Wall Connector (even though the Tesla Wall Connector like all EVSE has built in GFCI protection.) One risk is that someone could drill or hammer into extruded metal conduit feeding the EVSE/Wall Connector and damage the wiring inside the conduit, be electrocuted.

The GFCI that is built into the Tesla Mobile Connector, Tesla Wall Connector and other EVSE is there to protect the user when plugging the charging connector into the EV (even when the ground is wet, raining or snowing, etc.)

Most users have no issue with using the Tesla Mobile Connector with any of the power plug adapters where the receptacle/circuit has GFCI. If the circuit GFCI trips the solution may be to replace the GFCI receptacle or GFCI circuit breaker with one that is slightly less sensitive. Electrical Supply houses are one source for less sensitive GFCI equipment for specific applications.
 
What happens if I put a GFCI breaker in the panel and then plug a GFCI protected Mobile Connector into that GFCI protected outlet to charge my EV? In my experience and based on verbal answers from an experienced electrician who has installed many EV circuits: When you have two GFCI devices on the same circuit, it may work briefly, but then one of the GFCI breakers will trip and shut off the circuit.
and yes if you put two GFCIs in series on a single circuit, one of the GFCIs will trip.
These answers have a tiny, tiny nugget of truth buried in there, but it's mostly misleading.

First off, what is false:
The multiple GFCI's don't affect each other in any way, so stacking two of them in the circuit path isn't really doing anything at all to the other one making it more likely to trip. So that's not real.

What is true:
GFCI's are notoriously temperamental finnicky little buggers, and have a high rate of nuisance tripping or getting out of spec quickly. So all this is doing is a statistical thing, where you have now put two chances of that happening in line, so the % chance of failure goes up. It's like the chances of drawing something from a deck of cards, but you're now taking two draws from the deck instead of just one.

So yes, there is more chances of a failure, just because there are more of them that can potentially fail.
His advice to me (for installing an outlet for EV charging) was that you should install a GFCI breaker in the panel just to pass inspection, but then take the GFCI breaker out and put a standard breaker in the panel.
Sigh. An experienced electrician is intentionally recommending that you violate NEC? Run away. It is a real code requirement, so it's just pushing toward that it's easier and more reliable to just do hard wired devices from the start instead of outlets with plug-in devices.
 
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Longer reply below, but the short answer is: Yes it is internally GFCI protected, and yes if you put two GFCIs in series on a single circuit, one of the GFCIs will trip.

I'm no expert either but I think your answer is the most direct and the most correct answer I've read in this thread (I only read the first and sixth pages).
The mobile connector will NOT automatically trip if put on a GFCI circuit. If so, it would be literally impossible to use one in a code compliant installation. It can happen, but it means the GFCI breaker or outlet, or the mobile connector itself is faulty.
 
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Bottom left is a GFCI for my 14-50 mobile connector (GFCI), Bottom right is my hardwired HPWC (non-GFCI). Safe, to code, and no GFCI trips.
20230907_205217.jpg
 
These answers have a tiny, tiny nugget of truth buried in there, but it's mostly misleading.

First off, what is false:
The multiple GFCI's don't affect each other in any way, so stacking two of them in the circuit path isn't really doing anything at all to the other one making it more likely to trip. So that's not real.

What is true:
GFCI's are notoriously temperamental finnicky little buggers, and have a high rate of nuisance tripping or getting out of spec quickly. So all this is doing is a statistical thing, where you have now put two chances of that happening in line, so the % chance of failure goes up. It's like the chances of drawing something from a deck of cards, but you're now taking two draws from the deck instead of just one.

So yes, there is more chances of a failure, just because there are more of them that can potentially fail.
Sigh. An experienced electrician is intentionally recommending that you violate NEC? Run away. It is a real code requirement, so it's just pushing toward that it's easier and more reliable to just do hard wired devices from the start instead of outlets with plug-in devices.
Thank you. I can add that I have a 30A GFCI protected outlet at my cabin and I have yet to have it trip from plugging my mobile connector in.

I fall back to my standard warning: "The code was written by people with more experience and broader perspective than you so you should think twice before ignoring it."