Tesla Gen 3 Wall Connector--Exact Ground Fault Trip Threshold?

[wwhitney]

Does anyone know the ground fault current at which the Tesla Gen 3 Wall Connector will trip? The manual says it has a GFCI built-in, but it doesn't specify a Class or trip threshold.

Your typical GFCI receptacle is Class A which means it has to trip at 4-6 ma. Then there's Class B and Class C and maybe some Special Purpose GFCIs that are all allowed to have a higher trip threshold, e.g. 20 or 30 ma.

Thanks,
Wayne

 

[wwhitney]

I took a closer look at the manual, and I see it says "Ground Fault Circuit Interrupter Integrated -- no additional required (CCID20)." That term CCID20 is apparently from UL 2231-2 and refers to a 15-20 ma trip threshold.

So the Wall Connector does not provide Class A GFCI protection. And that definitely means that Class A GFCI protection must be provided on the supply to the EVSE in the locations that the NEC requires it. For the 2020 NEC, that's any EVSE connected to a receptacle (plugged in), or any EVSE installed outdoors at a dwelling unit on a circuit this is 50A or less.

Cheers, Wayne

 

[holeydonut]

I took a closer look at the manual, and I see it says "Ground Fault Circuit Interrupter Integrated -- no additional required (CCID20)." That term CCID20 is apparently from UL 2231-2 and refers to a 15-20 ma trip threshold.

So the Wall Connector does not provide Class A GFCI protection. And that definitely means that Class A GFCI protection must be provided on the supply to the EVSE in the locations that the NEC requires it. For the 2020 NEC, that's any EVSE connected to a receptacle (plugged in), or any EVSE installed outdoors at a dwelling unit on a circuit this is 50A or less.

Cheers, Wayne

The installation manual says not to use a GFCI breaker for a Gen 3 wall connector. Are you saying for 2020 NEC, that a GFCI breaker is indeed required?

 

[mongo]

I took a closer look at the manual, and I see it says "Ground Fault Circuit Interrupter Integrated -- no additional required (CCID20)." That term CCID20 is apparently from UL 2231-2 and refers to a 15-20 ma trip threshold.

So the Wall Connector does not provide Class A GFCI protection. And that definitely means that Class A GFCI protection must be provided on the supply to the EVSE in the locations that the NEC requires it. For the 2020 NEC, that's any EVSE connected to a receptacle (plugged in), or any EVSE installed outdoors at a dwelling unit on a circuit this is 50A or less.

Cheers, Wayne

I don't have the code itself, but aren't the outdoor and EVSE requirements only for outlets/ receptacles, not hardwired units?
GFCI Protection Updates in the 2020 NEC

 

[wwhitney]

The installation manual says not to use a GFCI breaker for a Gen 3 wall connector. Are you saying for 2020 NEC, that a GFCI breaker is indeed required?

Several initial points (I see some of this repeats my earlier posts, which I didn't review until now):

- The installation manual doesn't get to modify the NEC requirements. If it really won't work with a GFCI breaker, then the manual is basically saying "don't install this product in the situations where the NEC requires GFCI--get a different one."

- The listing standard for EVSEs I believe includes a test as to whether the EVSE will work with upstream GFCI protection, and I believe it's required to. There's definitely a test along this line for "ground leakage current," I'd need to double check that the limits imposed are low enough to not trip a GFCI.

- The Gen 3 Wall Connector does not provide GFCI protection at the J1772 end. It provide a 15ma-20ma ground fault protection; when the NEC requires GFCI protection, it means a Class A GFCI that trips at a 4-6 ma current imbalance.

As to your question, the 2020 NEC requires GFCI protection upstream of the EVSE if (a) the EVSE is cord and plug connected or (b) it is outdoors on a 50A or smaller circuit.

So the only way to avoid the requirement is hardwire it and (a) install it indoors (in your garage) or (b) install it on a 60A circuit.

Cheers, Wayne

 

[wwhitney]

I don't have the code itself, but aren't the outdoor and EVSE requirements only for outlets/ receptacles, not hardwired units?
GFCI Protection Updates in the 2020 NEC

In NEC-speak, an outlet != a receptacle. An outlet is any point where you connect utilization equipment; hardwired equipment still has an outlet, just not a receptacle-type outlet.

The GFCI requirements are in NEC section 210.8. Most of them only cover receptacles, but 2020 NEC 210.8(F) covers all outdoor outlets at 1 and 2 family dwellings on circuits of 50A or less. So that covers hardwired equipment as well as cord and plug connected equipment.

Cheers, Wayne

 

[mongo]

Several initial points:

- The installation manual doesn't get to modify the NEC requirements. If it really won't work with a GFCI breaker, then the manual is basically saying "don't install this product in the situations where the NEC requires GFCI--get a different one."

- The listing standard for EVSEs I believe includes a test as to whether the EVSE will work with upstream GFCI protection, and I believe it's required to. There's definitely a test along this line for "ground leakage current," I'd need to double check that the limits imposed are low enough to not trip a GFCI.

- The Gen 3 Wall Connector does not provide GFCI protection at the J1772 end. It provide a 15ma-20ma ground fault protection; when the NEC requires GFCI protection, it means a Class A GFCI that trips at a 4-6 ma current imbalance.

As to your question, the 2020 NEC requires GFCI protection upstream of the EVSE if (a) the EVSE is cord and plug connected or (b) it is outdoors on a 50A or smaller circuit.

So the only way to avoid the requirement is to (a) install it indoors (in your garage) or (b) install it on a 60A circuit.

Cheers, Wayne

There is a current level for self test which would need to be below 4mA to prevent tripping upstream GFCIs. However, the reason for a 20mA GFCI in the EVSE is due to the leakage and filter capacitance in the vehicle charger (along with any resistive leakage) which could nuisance trip a normal GFCI, and still will if one is upstream.

In NEC-speak, an outlet != a receptacle. An outlet is any point where you connect utilization equipment; hardwired equipment still has an outlet, just not a receptacle-type outlet.

The GFCI requirements are in NEC section 210.8. Most of them only cover receptacles, but 2020 NEC 210.8(F) covers all outdoor outlets at 1 and 2 family dwelling on circuits of 50A or less. So that covers hardwired equipment as well as cord and plug connected equipment.

Cheers, Wayne

Geeze, I blew reading comprehension on that one. From my link: "The use of the term outlets in the requirement makes it clear that GFCI protection is required if the equipment is cord and plug connected or hard-wired."

 

[wwhitney]

There is a current level for self test which would need to be below 4mA to prevent tripping upstream GFCIs. However, the reason for a 20mA GFCI in the EVSE is due to the leakage and filter capacitance in the vehicle charger (along with any resistive leakage) which could nuisance trip a normal GFCI, and still will if one is upstream.

That is a good point. So a corollary of the newish GFCI requirements for EVSEs in the 2020 NEC is that EVs better not have more than 4mA of leakage current. (BTW, the EVSE standard does include an option for CCID5, which is similar to a Class A GFCI).

Or a special more tightly calibrated GFCI could be used to allow up to 6 mA of leakage current. The Class A GFCI standard requires GFCIs to not trip below 4 mA, and to trip above 6 mA (at a speed depending on the current level), but tripping between 4 and 6 ma is optional.

Cheers, Wayne

 

[holeydonut]

...

So the only way to avoid the requirement is hardwire it and (a) install it indoors (in your garage) or (b) install it on a 60A circuit.

Hmmm that link Mongo just reference says:

Our last stop is Section 625.54, which covers electric vehicle charging systems with regards to GFCI protection for personnel. The protection requirements have been expanded to require all receptacles installed for the connection of electric vehicle charging to have GFCI protection. The previous requirements of single-phase, 150 volts to ground or less, and 50 amperes or less have been removed. These changes were made to clarify the intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings.

------------------------------------

So does this mean a Gen 3 TWC simply cannot be used with this 2020 NEC rules? Because you can't use an upstream GFCI breaker with the Gen 3 TWC and it doesn't meet GFCI requirements "at the outlet"?

 

[mongo]

That is a good point. So a corollary of the newish GFCI requirements for EVSEs in the 2020 NEC is that EVs better not have more than 4mA of leakage current. (BTW, the EVSE standard does include an option for CCID5, which is similar to a Class A GFCI).

Or a special more tightly calibrated GFCI could be used to allow up to 6 mA of leakage current. The Class A GFCI standard requires GFCIs to not trip below 4 mA, and to trip above 6 mA (at a speed depending on the current level), but tripping between 4 and 6 ma is optional.

Cheers, Wayne

Yeah, I was involved with EVSE in the early 2000s when they definitely needed higher trip points. Modern cars could be lower.

 

[mongo]

Hmmm that link Mogo just reference says:

Our last stop is Section 625.54, which covers electric vehicle charging systems with regards to GFCI protection for personnel. The protection requirements have been expanded to require all receptacles installed for the connection of electric vehicle charging to have GFCI protection. The previous requirements of single-phase, 150 volts to ground or less, and 50 amperes or less have been removed. These changes were made to clarify the intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings.

------------------------------------

So does this mean a Gen 3 TWC simply cannot be used with this 2020 NEC rules? Because you can't use an upstream GFCI breaker with the Gen 3 TWC and it doesn't meet GFCI requirements "at the outlet"?

Receptacle means plug in. Outlet can mean hardwired.

But yeah, it seems a Gen 3 outdoors needs a 60 Amp circuit to make everybody happy. No reason you couldn't then set it to a lower charge current though.

 

[holeydonut]

Receptacle means plug in. Outlet can mean hardwired.

But yeah, it seems a Gen 3 outdoors needs a 60 Amp circuit to make everybody happy. No reason you couldn't then set it to a lower charge current though.

The way that article reads; I feel even a 60A circuit regardless of indoor/outdoor ... outlet/plug ... phase-of-the-moon won't make NEC happy if the GFCI doesn't meet the Class-A-whatevers that Wayne was talking about.

 

[mongo]

The way that article reads; I feel even a 60A circuit regardless of indoor/outdoor ... outlet/plug ... phase-of-the-moon won't make NEC happy if the GFCI doesn't meet the Class-A-whatevers that Wayne was talking about.

I think 60 Amp outdoor outlets (hardwired) do not need GFCI:
"All other outdoor outlets that are supplied by single-phase branch circuits rated 150 volts or less to ground, 50 amperes or less, are now required to have GFCI protection for personnel."

A 60 amp receptacle (plug in) would:" The protection requirements have been expanded to require all receptacles installed for the connection of electric vehicle charging to have GFCI protection. <snip> These changes were made to clarify the intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings."

This also showns the mobile connector + vehicle must work reasonably well with normal GFCI.

 

[holeydonut]

I think 60 Amp outdoor outlets (hardwired) do not need GFCI:
"All other outdoor outlets that are supplied by single-phase branch circuits rated 150 volts or less to ground, 50 amperes or less, are now required to have GFCI protection for personnel."

A 60 amp receptacle (plug in) would:" The protection requirements have been expanded to require all receptacles installed for the connection of electric vehicle charging to have GFCI protection. <snip> These changes were made to clarify the intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings."

This also showns the mobile connector + vehicle must work reasonably well with normal GFCI.

This phrase literally says any EVSE circuit (even a 60A one) would need GFCI:

"...intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings."


But for real. I don't care about all this since I already have my two Gen 3 wall connectors on my house. And they ain't going anywhere hahaha.

 

[mongo]

This phrase literally says any EVSE circuit (even a 60A one) would need GFCI:

"...intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings."


But for real. I don't care about all this since I already have my two Gen 3 wall connectors on my house. And they ain't going anywhere hahaha.

Key phrase: "all cord and plug connected", wall connector is hardwired, not cord and plug.

 

[holeydonut]

Key phrase: "all cord and plug connected", wall connector is hardwired, not cord and plug.

But Wayne said 2020 NEC 210.8(F) covers cord and plug as well as hard-wired. So wouldn't 2020 NEC 625.54 still need to adhere to the GFCI requirements from 210.8 regardless?

BTW, I think a hardwired Gen 3 TWC still has a cord and plug ... since I back over the cord and plug with my Tesla all the time

 

[mongo]

But Wayne said 2020 NEC 210.8(F) covers cord and plug as well as hard-wired. So wouldn't 2020 NEC 625.54 still need to adhere to the GFCI requirements from 210.8 regardless?

BTW, I think a hardwired Gen 3 TWC still has a cord and plug ... since I back over the cord and plug with my Tesla all the time

What he wrote:

Most of them only cover receptacles, but 2020 NEC 210.8(F) covers all outdoor outlets at 1 and 2 family dwellings on circuits of 50A or less.

Also:

 

[h2ofun]

This phrase literally says any EVSE circuit (even a 60A one) would need GFCI:

"...intent of providing GFCI protection for personnel and all cord and plug connected electric vehicle power transfer equipment, regardless of phase, voltage or amperage ratings."


But for real. I don't care about all this since I already have my two Gen 3 wall connectors on my house. And they ain't going anywhere hahaha.

2 wimp, I am working in getting 5 gen 3s working

 

[wwhitney]

But Wayne said 2020 NEC 210.8(F) covers cord and plug as well as hard-wired. So wouldn't 2020 NEC 625.54 still need to adhere to the GFCI requirements from 210.8 regardless?

625.54 and 210.8 are separate requirements and you have to comply with each one individually; they don't interact. 625.54 covers all EVSEs connected with a receptacle. 210.8(F) cover all outdoor outlets at 1 and 2 family dwelling units that are on 50A or smaller circuits. So if you avoid using a receptacle, and you avoid being outdoors at 50A or less, then you can avoid a GFCI.

I.e. to avoid GFCI for a Gen 3 Wall Connector, you'd need the EVSE to be hardwired for sure, and then either indoors, or outdoors but on a 60A circuit (since that's the highest a Gen 3 Wall Connector supports, and 60A is the next breaker size up from 50A). Which is what I said in post #5.

Cheers, Wayne

 

[holeydonut]

625.54 and 210.8 are separate requirements and you have to comply with each one individually; they don't interact. 625.54 covers all EVSEs connected with a receptacle. 210.8(F) cover all outdoor outlets at 1 and 2 family dwelling units that are on 50A or smaller circuits. So if you avoid using a receptacle, and you avoid being outdoors at 50A or less, then you can avoid a GFCI.

I.e. to avoid GFCI for a Gen 3 Wall Connector, you'd need the EVSE to be hardwired for sure, and then either indoors, or outdoors but on a 60A circuit (since that's the highest a Gen 3 Wall Connector supports, and 60A is the next breaker size up from 50A). Which is what I said in post #5.

Cheers, Wayne

I feel like you've identified an unintended loophole of the rules, not necessarily something they wanted to build in.

Like it seems they just want to make EV charging safer. So excluding a 60A breaker-hard-wired-#6-THHN-EVSE just because the breaker is 60A doesn't make sense to me.