# EVSE GFCI redux - 2017 nec TIA 625.54



## HackWork (Oct 2, 2009)

What if it's not for an electric vehicle? You are just installing an outlet for an RV or welder, right? :wink:

As for vehicle chargers not working with GFCI protection, I never knew that. Why don't they work? How do they know? What happens in commercial buildings with GFP mains? Sounds fishy.


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## MTW (Aug 28, 2013)

Only one month to go before this travesty is adopted in Massachusetts. :furious:


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## Awg-Dawg (Jan 23, 2007)

That’s a poorly written requirement.

The way it reads, if you have a 125/250v receptacle, it would need protection.

If you had a 250v receptacle, you wouldn’t.


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## CoolWill (Jan 5, 2019)

Awg-Dawg said:


> That’s a poorly written requirement.
> 
> The way it reads, if you have a 125/250v receptacle, it would need protection.
> 
> If you had a 250v receptacle, you wouldn’t.


250 V is still "150 V to ground or less".


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## Awg-Dawg (Jan 23, 2007)

CoolWill said:


> 250 V is still "150 V to ground or less".


The circuit voltage could be, but the voltage rating if the receptacle isn’t.

It says “receptacle” rating not circuit rating.


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## splatz (May 23, 2015)

CoolWill said:


> 250 V is still "150 V to ground or less".





Awg-Dawg said:


> The circuit voltage could be, but the voltage rating if the receptacle isn’t.
> 
> It says “receptacle” rating not circuit rating.



Of course a receptacle has a voltage rating, but does a receptacle have a voltage-to-ground rating?


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## Awg-Dawg (Jan 23, 2007)

splatz said:


> Of course a receptacle has a voltage rating, but does a receptacle have a voltage-to-ground rating?


The whole thing was terribly written, the next code cycle changes it to say circuit.


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> The circuit voltage could be, but the voltage rating if the receptacle isn’t.
> 
> It says “receptacle” rating not circuit rating.


As a receptacle rated 250V single phase, that means that it is rated under 150V to ground.


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## kb1jb1 (Nov 11, 2017)

I do not have the 2020 code yet but I believe it applies to all receptacles 50 amps or less and 150 volts to ground ( earth ). Ground, grounding, and grounded are sometimes interchanged. I like to use the term Earth and Neutral depending on the situation. Or White and Green depending on who I am talking with.

As I said before, we have to protect the general people from their own stupidity. We as electricians know what we can or should do when it comes to electric equipment. But the millennial who just bought his new TESLA has no idea of what electricity can do. I believe the " thing on the wall" is only a power port and the charger is part of the car. Things get abused by the user and could pose a danger down the road. 
If you think about it, every industry is putting " safety measures" into their codes. We have AFCI & GFCI. Cars now have back up alarms and cameras, They are mandating CO and gas detectors. Houses need re-enforced hurricane strapping. Bicycle helmets. Red fire caulk when in most cases regular thermal caulk will do.


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## mikewillnot (Apr 2, 2013)

Most of the replies above are off topic, in a way. I'm concerned about the GFCI problem, and the requirement to put 2 in series, which usually doesn't work.


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## HackWork (Oct 2, 2009)

mikewillnot said:


> Most of the replies above are off topic, in a way. I'm concerned about the GFCI problem, and the requirement to put 2 in series, which usually doesn't work.


 My reply was right on topic.

Can you please explain how/why it doesn't work?


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> As a receptacle rated 250V single phase, that means that it is rated under 150V to ground.


 A 480v receptacle would apply also then wouldn’t it?


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> A 480v receptacle would apply also then wouldn’t it?


No, because that is 277V to ground.


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## splatz (May 23, 2015)

HackWork said:


> As a receptacle rated 250V single phase, that means that it is rated under 150V to ground.


I don't see it that way. 



For example, a NEMA 6-50R is RATED for 250V irrespective of the voltage to ground; the rating doesn't mention to 150V to ground. If it so happens that it's installed with 240V coming from the usual residential split phase supply, then 150V to ground. If it happens to be supplied by, say, the high leg of a high leg delta, and one of the other legs, with no neutral, then it is not operating at <150V to ground.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> No, because that is 277V to ground.


 How can a 250v receptacle be 150v or less and not a 480v?

They are both over 150v.


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## HackWork (Oct 2, 2009)

splatz said:


> If it happens to be supplied by, say, the high leg of a high leg delta, and one of the other legs, with no neutral, then it is not operating at <150V to ground.


And then it wouldn't need GFCI protection.


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> How can a 250v receptacle be 150v or less and not a 480v?
> 
> They are both over 150v.


A nominal 250v feed is 125V to ground, which is less than 150V.

A nominal 480V feed is 277V to ground, which is more than 150A.

Int he super odd situation that splatz mentioned, then it wouldn't apply and GFCI protection wouldn't be required.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> A nominal 250v feed is 125V to ground, which is less than 150V.
> 
> A nominal 480V feed is 277V to ground, which is more than 150A.
> 
> Int he super odd situation that splatz mentioned, then it wouldn't apply and GFCI protection wouldn't be required.


 

I understand what you’re saying, it’s just the wording doesn’t agree with it. 

You’re saying circuit voltage , the wording is saying receptacle voltage.


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> I understand what you’re saying, it’s just the wording doesn’t agree with it.
> 
> You’re saying circuit voltage , the wording is saying receptacle voltage.


It's the same both ways.

Test that receptacle to ground and you will get less than 150v. The nominal voltage will also be less than 150V.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> It's the same both ways.
> 
> Test that receptacle to ground and you will get less than 150v. The nominal voltage will also be less than 150V.


 A 480v ungrounded system might show less than 150v to ground.


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> A 480v ungrounded system might show less than 150v to ground.


Then you wouldn't need GFCI protection.

You know the meaning, there is no question. I think this is silly.

If you want to pick something apart for the sake of picking something apart, there is far better code articles to do it with.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> Then you wouldn't need GFCI protection.
> 
> You know the meaning, there is no question. I think this is silly.
> 
> If you want to pick something apart for the sake of picking something apart, there is far better code articles to do it with.


 I’m not picking anything apart, I’m only commenting on what it says.

Using your logic , you’re could spend thousands of dollars on gfcis in a Restaurant, I’m only saying that the wording says it’s not provided.


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> I’m not picking anything apart, I’m only commenting on what it says.


 You are most certainly picking it apart. It's very clear, there is no question.



> Using your logic , you’re could spend thousands of dollars on gfcis in a Restaurant


 I don't know what that means.



> I’m only saying that the wording says it’s not provided.


I don't know what this means either.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> You are most certainly picking it apart. It's very clear, there is no question.
> 
> I don't know what that means.
> 
> ...


 It’s very clear, i read it like it says.

You read it by adding circuit to the wording, which it doesn’t, that clearly changes the requirement.


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## Dennis Alwon (May 9, 2009)

mikewillnot said:


> The problem is that every brand of EV charger (EVSE) that I install, both hard-wired and plug-in models, has GFCI built in. Over a number of experiments so far, when plugged into a circuit protected by a (pricey) GFCI breaker, they do not function. They REQUIRE NO GFCI.
> 
> So now what???
> 
> View attachment 138400


Mike are you sure it has gfci and not gfp built in. If they are both GFCI then there should be no reason for trouble however if there is gfp in the unit and then you install a gfci then I can see a possibility of an issue since they trip at different limits


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> It’s very clear, i read it like it says.
> 
> You read it by adding circuit to the wording, which it doesn’t, that clearly changes the requirement.


I didn't add anything to it. 

You can pick apart at least a third of the code to find little, tiny, minuscule ways to say how it's not exact int he same way as you are doing here, but we all know exactly what it means, like we do here.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> I didn't add anything to it.
> 
> You can pick apart at least a third of the code to find little, tiny, minuscule ways to say how it's not exact int he same way as you are doing here, but we all know exactly what it means, like we do here.


 I agree that we all know what the intent is.


The CMP does as well and have changed it to read that.


Again, I’m not picking anything apart, I’m only commenting on what it says.


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## HackWork (Oct 2, 2009)

> The CMP does as well and have changed it to read that.


 The CMP has HUNDREDS of other code articles that needs to be addressed first. Code that actually makes us do different installations in different municipalities because the AHJ's see the code completely differently than each other. 

This is not one of those instances, everyone know exactly what it means.


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## Awg-Dawg (Jan 23, 2007)

HackWork said:


> everyone know exactly what it means.


 

Apparently not,lol.


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## HackWork (Oct 2, 2009)

Awg-Dawg said:


> Apparently not,lol.


The only person who doesn't know what it means is someone who is picking it apart. 

How about getting back to the topic of the thread?

Will a ground fault protected vehicle charger trip a ground fault protected outlet? And how does one differentiate between a receptacle for vehicle charging and one for any of the many other purposes that people use 50A receptacles for?


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## JoeSparky (Mar 25, 2010)

Looks like we are all installing nema 14-50 RV outlets now. More importantly, when was the last time any of us have pulled a permit :no: to install an EV outlet? How soon before they eliminate the neutral bus terminals in Resi loadcenters?


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## micromind (Aug 11, 2007)

HackWork said:


> As a receptacle rated 250V single phase, that means that it is rated under 150V to ground.


Slightly out of context here but if the recept. was fed by the high leg of a 120/240 3Ø 4 wire ∆ system and one of the other phases, it'd be more than 150 volts to ground.


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## HackWork (Oct 2, 2009)

micromind said:


> Slightly out of context here but if the recept. was fed by the high leg of a 120/240 3Ø 4 wire ∆ system and one of the other phases, it'd be more than 150 volts to ground.


And then you wouldn't have to GFCI protect it. You also wouldn't have to GFCI protect it if the customer says they are going to plug their RV into it.


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## Dennis Alwon (May 9, 2009)

HackWork said:


> And then you wouldn't have to GFCI protect it. You also wouldn't have to GFCI protect it if the customer says they are going to plug their RV into it.


Well you would have to gfci protect it in 2020 which is what the op was talking about. 



> 210.8(A) Dwelling Units.
> *All 125-volt through 250-volt receptacles *installed in the locations specified in 210.8(A)(1) through (A)⁠(11) and supplied by single-phase branch circuits rated 150 volts or less to ground shall have ground-fault circuit-interrupter protection for personnel.





> 210.8(B) Other Than Dwelling Units.
> *All 125-volt through 250-volt receptacles* supplied by single-phase branch circuits rated 150 volts or less to ground, 50 amperes or less, and all receptacles supplied by three-phase branch circuits rated 150 volts or less to ground, 100 amperes or less, installed in the locations specified in 210.8(B)(1) through (B)(12) shall have ground-fault circuit-interrupter protection for personnel.


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## mikewillnot (Apr 2, 2013)

Dennis Alwon said:


> Mike are you sure it has gfci and not gfp built in. If they are both GFCI then there should be no reason for trouble however if there is gfp in the unit and then you install a gfci then I can see a possibility of an issue since they trip at different limits



[OP] Thanks for the on-topic reply, Dennis. 

The answer is, I don't know exactly what's built into the chargers. Details are not in the specs that I have access to, unless I missed something several times. The problem occurs with every brand of EVSE I've tried (about 5), several of which claim somewhere in their lit or in their support emails to have GFCI built in. If it's GFPE, that's worth knowing, I suppose, although I don't know enough about the technology itself to understand why if both are GFCI, they should work in series. I'll do some more research. 

What I DO know is that with a number of different brands now, plugging their unit into a GFCI-protected outlet (various brands of breaker) causes instant trip. Going back to a normal breaker -- no problem.


One manufacturer actually specifies that the outlet _must not be GFCI protected_.


Whatever's in there, its function poses an obvious compliance problem.


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## mikewillnot (Apr 2, 2013)

JoeSparky said:


> Looks like we are all installing nema 14-50 RV outlets now. More importantly, when was the last time any of us have pulled a permit :no: to install an EV outlet? How soon before they eliminate the neutral bus terminals in Resi loadcenters?



[OP] Off topic, but:
We're NOT all installing 14-50. A number of the EVSE models/brands I install come, or CAN come with, 6-50 plugs. For this application, the 14-50 is overkill and a waste of wire anyway, as none of the "level 2" chargers actually require or use a neutral. AFAIK, the only (resi) customers I interact with who can ever expect to NEED a neutral are those who might someday want to plug in an RV.


From what history I know, the origins of the EVSE industry's "standardization" on the 14-50 can be found in the early days of the Tesla Roadster, when the company determined that the best odds for finding a 240-volt outlet "in the wild" was in RV parks.


No matter, probably. I understand that technologically, Beta was actually superior to VHS.


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## mikewillnot (Apr 2, 2013)

HackWork said:


> You also wouldn't have to GFCI protect it if the customer says they are going to plug their RV into it.



I can't legally do this, as EVSE is almost all we do, and I often include the hardware with the sale, and usually/always hang it on the wall, plug it in, activate it, etc. I also specify in our agreements that our work is code compliant. What the customer :wink: "says" won't fly.


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## HackWork (Oct 2, 2009)

mikewillnot said:


> I can't legally do this, as EVSE is almost all we do, and I often include the hardware with the sale, and usually/always hang it on the wall, plug it in, activate it, etc. I also specify in our agreements that our work is code compliant. What the customer :wink: "says" won't fly.


If you are providing the charger, why are you using the plug-in models? The only time I install those is when the customer already bought it that way. Most customers buy the hardwired model and when they ask me beforehand that is what I recommend as well.


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## Dennis Alwon (May 9, 2009)

Some of those units come with a cord so short that they cannot plug into a receptacle with an in-use cover. We have been disconnecting the cord and doing a direct wire. Not sure if that is allowed but that is what we are doing.

It is literally impossible to use the 6" of cord and plug that they supply unless it is indoor.


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## mikewillnot (Apr 2, 2013)

HackWork said:


> If you are providing the charger, why are you using the plug-in models? The only time I install those is when the customer already bought it that way. Most customers buy the hardwired model and when they ask me beforehand that is what I recommend as well.



Good points. I guess this is where it's all going, isn't it. The only reasons I can see for a non-hardwired approach are (1) the RV scenario and (2) the possibility of an upcoming (1-2 yrs) house sale, and the desire to take the charger along. 

There was one other. Manufacturers for years have floated at times the notion of charger portability -- as in, "you can take it with you on vacation, to your second home." As far as I can see, if you can afford a second home, you can afford a second charger.


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## HackWork (Oct 2, 2009)

Dennis Alwon said:


> Some of those units come with a cord so short that they cannot plug into a receptacle with an in-use cover. We have been disconnecting the cord and doing a direct wire. Not sure if that is allowed but that is what we are doing.
> 
> It is literally impossible to use the 6" of cord and plug that they supply unless it is indoor.


Code requires the cord&plug to be no more than 12". Even at the full 12" (as you mentioned) there is no way to use an outlet with an outdoor in-use cover without putting stress on the cord, plug, and outlet. I don't like it at all, and many manufacturers say that the cord&plug models are for indoor use only.

They work fine when mounting the unit indoors and orienting the outlet upsidedown underneath the charger or sideways next to the charger.

As you know, removing the cord&plug to hardwire it is against code and many chargers are not meant to be opened at all. You'd be better off just getting the hardwired model.


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## HackWork (Oct 2, 2009)

mikewillnot said:


> Good points. I guess this is where it's all going, isn't it. The only reasons I can see for a non-hardwired approach are (1) the RV scenario and (2) the possibility of an upcoming (1-2 yrs) house sale, and the desire to take the charger along.


 I agree on your first reason. As for the second, I tell them that it is still advisable to use the hardwireable model. I explain that it's simple to disconnect the hardwired unit (I will do it for a minimal service call fee if they don't feel comfortable) and that leaving the box there with the feed will allow the next owner to connect their own charger, which is a selling point. In some areas they require new houses to be "EVSE Ready" and this is how I have seen it done, a feed going to an outdoor box. So that is how I install them, I just bring the whip into that outdoor box and splice it. I mainly install Clippercreek chargers which have the whip ready to go.



> There was one other. Manufacturers for years have floated at times the notion of charger portability -- as in, "you can take it with you on vacation, to your second home." As far as I can see, if you can afford a second home, you can afford a second charger.


I had one customer with this idea. I told them that I had to solidly mount the charger to the house and it was not ruggedized or meant to be carried around like a portable unit. Once they saw the unit and how cumbersome it was, they gave up on that idea.

If they really want to do it, I will do whatever they want.


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## CoolWill (Jan 5, 2019)

JoeSparky said:


> More importantly, when was the last time any of us have pulled a permit :no: to install an EV outlet?


Apparently, everyone in Canada, replete with load shedders and a load calc.:vs_OMG:


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## Dennis Alwon (May 9, 2009)

mikewillnot said:


> Good points. I guess this is where it's all going, isn't it.


I think you've been spending too much time eating those delicious Zwigles hot dogs that you have in Rochester. My wife is distantly related to them and they would occasionally send us a care package but I guess the kids run it now.


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## mikewillnot (Apr 2, 2013)

Dennis Alwon said:


> Some of those units come with a cord so short that they cannot plug into a receptacle with an in-use cover. We have been disconnecting the cord and doing a direct wire. Not sure if that is allowed but that is what we are doing.
> 
> It is literally impossible to use the 6" of cord and plug that they supply unless it is indoor.



That too.


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## mikewillnot (Apr 2, 2013)

Dennis Alwon said:


> I think you've been spending too much time eating those delicious Zwigles hot dogs that you have in Rochester. My wife is distantly related to them and they would occasionally send us a care package but I guess the kids run it now.



PM me an address and we will "rectify" that. :smile:


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## EtrnlFlux (Aug 8, 2018)

mikewillnot said:


> My local inspector provided me with the attached TIA, going into effect around here in February/March 2020, which states:
> 
> 625.54 Ground-Fault Circuit-Interrupter Protection for Personnel. *All single-phase receptacles installed for the connection of electric vehicle charging that are rated 150 volts to ground or less, and 50 amperes or less* shall have ground-fault circuit-interrupter protection for personnel. [emphasis added]
> 
> ...


So if you used lets say 6/3 THHN, with a 60amp recp. You could technically ignore this code, since it is 150v or less to ground AND 50 amp or less. So just get a reading over 50 amps and you're free and clear.


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## mikewillnot (Apr 2, 2013)

Dennis Alwon said:


> Mike are you sure it has gfci and not gfp built in. If they are both GFCI then there should be no reason for trouble however if there is gfp in the unit and then you install a gfci then I can see a possibility of an issue since they trip at different limits


 I've learned a bit more about the difference between GFCI and GFP. Essentially, sensitivity: 5 ma fault vs 30 ma fault. I still don't understand why GFCI and GFP in series would be any more or less likely to have problems than GFCI and GFCI. 

Also: I spoke to a tech at ClipperCreek today, and he explained that their unit has 20ma GFI protection built-in ... which I believe makes it Class B, which is only for swimming pool lights (HERE). He seemed to think that such a device would somehow make theirs more robust than the finicky GFCI breakers I'm using (i.e. what's available), I guess, which would somehow make mine (GFCI breaker) redundant or not necessary. I sent him the 2017 NEC TIA 17-2. They're looking into it. :surprise: They're not "mine," as in something I'm throwing in for the fun of it. They're code-required. 

ChargePoint includes in their installers' literature instructions to NOT connect their device to a GFCI-protected circuit. Contra to NEC, that is. So the OP problem is not my imagination. In series, they OFTEN don't play well together. 

Still no solution in sight... except that I'm now steering customers hard away from 240v outlet setups, towards hard-wired. I've told several customers lately that if they want a 240-volt outlet setup I would happily refer them to another electrician. That usually gets their attention.

I also don't understand why, given the NEC requirement, EVSE manufacturers are still selling (PUSHING) units that are equipped with both an input plug and GFCI technology built-in.


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## mikewillnot (Apr 2, 2013)

EtrnlFlux said:


> So if you used lets say 6/3 THHN, with a 60amp recp. You could technically ignore this code, since it is 150v or less to ground AND 50 amp or less. So just get a reading over 50 amps and you're free and clear.



No residential level2 EVSE comes equipped with a 60-amp plug. They're generally either NEMA 6-50 or 14-50. Also, on the one or two occasions I've tried, NO ONE locally stocks 60-amp receptacles.


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## HackWork (Oct 2, 2009)

I just looked, since this thread started I have installed 9 car chargers. All 9 of them were hardwired. No one asked for a plug-in model to be installed. They are not very common, my take is that the plug-in chargers are just a way for the charger manufacturers to sell their products to people who already have a 50A outlet.

And yes, I know that these are not actually "chargers" as that is built into the vehicle, but that is what we all call them.


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## mikewillnot (Apr 2, 2013)

HackWork said:


> my take is that the plug-in chargers are just a way for the charger manufacturers to sell their products to people who already have a 50A outlet.


Who has a 50-amp outlet in their *garage*? (Other than some RV owners?)

Two weeks back, installed what may be my last 1450 outlet, in a garage for a Porsche Taycan -- @$200k -- that came with an extremely over-engineered plug-in charger with wifi and lots of programmability and communications functionality, set up for a 1450 outlet -- like most stock car chargers seem to be. It's not just that nearly all aftermarket wall chargers are based on the 1450 (hard-wired models available); the CAR industry is "standardizing" on 1450.  So I have to address this GFCI question on almost every sale. Unless they're already away from the plug-in approach, as with the Tesla HPWC (hardwired only).

And I know there are trade-offs, regardless, that we talk about. E.g., if it were MY stock charger, it would live in the 1450 outlet normally, and when I go away on any kind of trip I'd forget to pack it and wind up somewhere wishing I had it.


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## HackWork (Oct 2, 2009)

mikewillnot said:


> Who has a 50-amp outlet in their *garage*? (Other than some RV owners?)


 Many people have 50A outlets in their garage or driveway for RVs as well as welders and electric vehicles. 



> Two weeks back, installed what may be my last 1450 outlet, in a garage for a Porsche Taycan -- @$200k -- that came with an extremely over-engineered plug-in charger with wifi and lots of programmability and communications functionality, set up for a 1450 outlet -- like most stock car chargers seem to be. It's not just that nearly all aftermarket wall chargers are based on the 1450 (hard-wired models available); the CAR industry is "standardizing" on 1450. So I have to address this GFCI question on almost every sale. Unless I can move them away from the plug-in approach.


 I don't see this at all, it's the exact opposite for me, as I posted.

A couple years ago when speaking directly with a higher level Clippercreek tech about how the cord&plug does not work with an in-use cover and asked how he recommend I install it, he literally told me that if I was installing new wiring/box that I should definitely use the hardwired model.


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## mikewillnot (Apr 2, 2013)

I raised the issue with ClipperCreek, and they have modified their recommendations policy, to _hardwired except when grandfathered_:


> Our recommendation for customers and installers would be to use a hardwired EVSE when purchasing and installing with new wiring and infrastructure. If the customer has a 240V outlet already installed in compliance with NEC code at the time (prior to requiring a GFCI) and would like to purchase an EVSE, we could recommend a plug type charging station (ideally for indoor use only).


They also said something interesting about GFCI breakers:



> I would encourage you to look into Class B GFCI breakers as they have a 20 mA threshold compared to Class A with a 5 mA trip point. From my reading into the NEC and recent changes, I can’t see anything that would consider this a code violation. A breaker with a 20 mA trip point should work perfectly with ClipperCreek EVSE’s as we test every unit and make sure that they trip the internal CCID when the current leakage is in the range of 16mA to 19mA.


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## tickthatbox (6 mo ago)

Awg-Dawg said:


> That’s a poorly written requirement.
> 
> The way it reads, if you have a 125/250v receptacle, it would need protection.
> 
> If you had a 250v receptacle, you wouldn’t.


250 receptacle still have a 125V pole to ground.


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## Almost Retired (Sep 14, 2021)

they worked it out over 2.5 years ago


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