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Outdoor NEMA 14-50 Enclosure

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GE 50 Amp Temporary RV Power Outlet-U054P - The Home Depot

Something similar to this is what I’ve seen at a lot of people do for an outdoor 14-50. I don’t own one personally but it’s what I’d want if I was doing an outdoor install

I vastly prefer this one:

The Eaton one is way better than the other one I bought from Home Depot (not sure if it was the GE one linked above or not)

https://www.homedepot.com/p/Eaton-5...Temporary-RV-Power-Outlet-Box-CHU1S/100565603

Now none of these are going to cover your EVSE, but they will cover the plug/receptacle.

I personally am not convinced that UMC units left outdoors all the time is a really good idea from a security and shock hazard standpoint. By default most say NEMA 14-50 receptacles I have seen are not on GFCI protected circuits. So there is a shock hazard when plugging them in upstream of the EVSE. The EVSE has its own built in GFCI so everything downstream is protected.

Note that in 2017 NEC in Article 625 is a new requirement that all EVSE receptacles be GFCI protected. Now I personally think this is an onerous requirement for receptacles installed in dry locations (like a garage) since the EVSE has built in GFCI protection, but for outdoor use I absolutely see the merits. The issues are that the GFCI breakers are stupid expensive (over $100) and you can't get them for all model of panels, you can't use Tandem breakers, etc... Oregon stripped many of the new GFCI requirements out of the 2017 NEC when they adopted it, but the committee did not have a chance to review this provision since it was added to 2017 NEC last minute through an emergency process.

So with that all being said, I am a much bigger fan of installing HPWC units outdoors. They don't require a GFCI breaker since they are hard wired and they are much more environment and vandal resistant.
 
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625.54 or 625.56 I believe. Am at dinner on my phone. I have posted about it elsewhere on this forum.
Looked it up, it is 625.54 - good memory!

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.
Does this apply to a 240v circuit? Obviously 240 > 150 but are they considering each 120v phase separately?
 
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thinking about doing this for a future house ill be living at, as it has no garage. Ill just tell the installer that its for an RV and no questions will be asked about EV charging :)

my only hope is nobody steals the UMC as i dont plan on unplugging it everyday.
 
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Looked it up, it is 625.54 - good memory!


Does this apply to a 240v circuit? Obviously 240 > 150 but are they considering each 120v phase separately?

Yes, this applies. Residential service in the US is 120/240v split phase, so this means neither "hot" leg is more than 150 volts to ground. So yes, they intend to require GFCI's on *ALL* EV outlets.

thinking about doing this for a future house ill be living at, as it has no garage. Ill just tell the installer that its for an RV and no questions will be asked about EV charging :)

my only hope is nobody steals the UMC as i dont plan on unplugging it everyday.

Hah, yes, I have never seen RV outlets with GFCI breakers, although, there does seem to be some debate as to if 2017 NEC intended to require them:

GFCI and RV parks

I think Oregon stripped a lot of the higher amperage GFCI requirements out of their adoption of the 2017 NEC (probably too costly still to justify).

I would call out that telling your electrician something is intended for an TV might result in different NEC load calculations (since RV's probably typically draw a fraction of what an EV does), so it could in theory make a difference (but yeah, in most practical situations, probably not).

As to the stealing of the UMC: Again, that is one reason I am a fan of the Wall Connector (though I am sure there are ways as others pointed out of building a custom enclosure for it).
 
I would call out that telling your electrician something is intended for an TV might result in different NEC load calculations (since RV's probably typically draw a fraction of what an EV does), so it could in theory make a difference (but yeah, in most practical situations, probably not).

As to the stealing of the UMC: Again, that is one reason I am a fan of the Wall Connector (though I am sure there are ways as others pointed out of building a custom enclosure for it).

The house has 100A service, but i'm pretty sure it can handle a 50A outlet that only charges up to 32A anyways (gen2 UMC). My parents house built in the 50s has a wall connector on a 50A circuit and its also on 100A service.

It's a small house (~1600sqft) in rhode island. If the electrician doesn't think it can support a 50A circuit though, ill relent and get a Wall connector on a smaller circuit. even 24A charging will fulfill my daily needs. I don't want to go that route though because i will be living there temporary, so a NEMA 14-50 makes more sense for temporary solutions vs long term (with the wall connector).
 
Yes, this applies. Residential service in the US is 120/240v split phase, so this means neither "hot" leg is more than 150 volts to ground. So yes, they intend to require GFCI's on *ALL* EV outlets.
I spoke to my electrician friend, who spoke to the engineer who designs all of the car charging installations for his company (a fairly large electrical company). He says that GFCI protection is not required for a 240v circuit.

I will be calling and talking to one of the city inspectors later today, hopefully he can bring some clarity to the situation.
 
I spoke to my electrician friend, who spoke to the engineer who designs all of the car charging installations for his company (a fairly large electrical company). He says that GFCI protection is not required for a 240v circuit.

I will be calling and talking to one of the city inspectors later today, hopefully he can bring some clarity to the situation.

I am genuinely curious what he would say about NEC 625.54. Would you mind asking him (send him a copy of the text of the article)?

GFCI is not required for hard wired HPWC’s but 625.54 is very clear that it is required for receptacles.

It is also possible that he is correct in the market he works in - either they may not have adopted 2017 NEC yet or they may have modified it.

Please report back on what your electrician friend and inspector say!
 
I am genuinely curious what he would say about NEC 625.54. Would you mind asking him (send him a copy of the text of the article)?

GFCI is not required for hard wired HPWC’s but 625.54 is very clear that it is required for receptacles.

It is also possible that he is correct in the market he works in - either they may not have adopted 2017 NEC yet or they may have modified it.

Please report back on what your electrician friend and inspector say!
I specifically mentioned 625.54, he said it doesn't apply to 240v circuits. Therefore 625.22 is the one to pay attention to. His words:

I spoke with our engineer and he elaborated on the requirements for GFCI in a situation like that, pretty much a dwelling unit receptacle like that is exempt. 625.22 is the major article to pay attention to, that puts the onus of personnel protection on the manufacturer of the vehicle. When we install charging stations all personnel protection is built in, be it GFCI or, I believe in Tesla’s case, CCID. This protection should be built into the cable plug for the Tesla charger.
As for the part that talks about 150 V to ground, that does not apply to a 240 V outlet. Only 120v circuits.
So technically, there has to be protection, but it’s not on the electrical installation side.

We do follow the 2017 NEC here. I'm wondering if they are getting mixed up between a hardwired EVSE vs the 14-50 outlet + UMC. As far as I know, the UMC doesn't have any sort of protection built in, correct?

I tried to connect with the city inspector (seeing as how he will be the one doing the actual inspection) but I wasn't able to get him on the phone today. He's supposed to call back so I will update this thread when I hear from him.
 
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