Outdoor NEMA 14-50 Enclosure

[Runt8]

@eprosenx The inspector called literally right as I posted my last message. He had actually never heard of 625.54. In his book it stops at 625.52 (oddly enough, my electrician friend has a NEC app on his phone that also stops at .52). I pointed him to the NFPA website and he saw .54 for the first time. After reading he agreed with the electrician that the GFCI protection doesn't apply to 240v circuits.

Depending on what I can find about what protection the UMC has built in I may use a GFCI breaker anyway. What's a hundred bucks when you're plugging in a $60k car?

 

[brkaus]

@eprosenx The inspector called literally right as I posted my last message. He had actually never heard of 625.54. In his book it stops at 625.52 (oddly enough, my electrician friend has a NEC app on his phone that also stops at .52). I pointed him to the NFPA website and he saw .54 for the first time. After reading he agreed with the electrician that the GFCI protection doesn't apply to 240v circuits.

Depending on what I can find about what protection the UMC has built in I may use a GFCI breaker anyway. What's a hundred bucks when you're plugging in a $60k car?

My understanding is the UMC has ground fault detection built in.

 

[SSonnentag]

I used one of these simple outdoor 14-50 enclosures for 3 years before redoing the entire setup for our two Teslas. We never had any issue with the plug, and this outlet sits out on our front porch where the wind and rain hit it every time it winds and rains.

 

[eprosenx]

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:



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.

So to be 100% clear:

GFCI breakers are NOT required if the EVSE (Wall Connector) is hardwired. However:

All EVSE's have GFCI built in from what I understand. They also have "contactors" in them that de-energizes the end of the EVSE cable port that goes into the car so that you can't shock yourself while plugging in the car. Once it is plugged in and the car is talking to the EVSE then it will energize the cable. Note that the GFCI ability inside the EVSE units only protects users downstream of the EVSE, not upstream at the receptacle the EVSE is plugged into (if it is not a hard wired unit). So the danger is that you are plugging in your UMC in the rain and you come in contact with one of the hot pins while doing so.

I should also call out that a UMC is an EVSE like any other and so it has a GFCI protection ability built in as well as a contactor (that is why it clicks when it engages just like the Wall Connector does).

Here is the full text of 625.54:

So a 240v receptacle in the US is generally considered by definition a single phase receptacle. It is typically 120v from "hot" to ground on each leg, 240v from hot to hot. So therefore it falls into the above of "150v to ground or less".

Ergo, you just have it on a GFCI.

I personally feel this is overkill for dry locations (considering the breaker cost is a difference of $10 vs. like $130 if you can get them) and it is ridiculous since I have never seen an RV park with GFCI breakers, but regardless, it is what is written in NEC 2017.

I have emailed with the Chief Inspector for Oregon and his feeling was that the committee did not intend to accept this change in the 2017 code, but it would appear it snuck through since it was an "emergency" last minute modification and it did not get reviewed as part of the code making process.

 

[Rocky_H]

Wow. Yeah, both of them are B.S.ing hard on their excuses of why they don't think it applies. "150 volts to ground or less" absolutely 100% applies to ALL 240V split phase outlets. There's no getting around that.

 

[brkaus]

But if you intend the 14-50 for an RV or industrial compressor, GFCI isn’t required?

 

[eprosenx]

But if you intend the 14-50 for an RV or industrial compressor, GFCI isn’t required?

Yeah, I think you are right (no GFCI required) if it is installed at a "Dwelling Unit". (though I have not exhaustively read all other code sections to verify)

625 only applies to EV's so an RV or industrial compressor is exempt.

Now 210.8(B) "Other Than Dwelling Units" does require GFCI's on 50 amp and lower receptacles (150 volts and less to ground) in a lot of cases. Specifically anywhere outside or wet (so that would include RV parks?) So I am assuming that only applies to commercial locations? Though not sure if it would apply if you have a shop building on your property or not? Depends on how far the definition of "Dwelling Unit" in article 100 is interpreted.

 

[reidthaler]

I'm thinking of installing an outdoor charger based on the following photo. (Forgive my hack Photoshop job) and was wondering if it's possible, safe, legal? I'm in northern CA. I would like to keep the cable plugged in at all times. Do I need to have another weatherproof box. for the cable organizer? I figured I could skip the cord retractor I was thinking of.

Of course, open to suggestions.

Thanks,

Reid

 

[Eno Deb]

The installation instructions for the cable organizer explicitly mention outdoor installation. Also, unless gravity suddenly reverses direction , I don't see how rain water could possibly get into the plug (and even if it did, nothing much would happen because there is no high voltage on the plug while it's not plugged in).

For installation of the NEMA 14-50 outlet I'd recommend to hire a licensed electrician. You'll also need a permit.

 

[eprosenx]

I'm thinking of installing an outdoor charger based on the following photo. (Forgive my hack Photoshop job) and was wondering if it's possible, safe, legal? I'm in northern CA. I would like to keep the cable plugged in at all times. Do I need to have another weatherproof box. for the cable organizer? I figured I could skip the cord retractor I was thinking of.

Of course, open to suggestions.

Thanks,

Reid

View attachment 333515

Downstream of the UMC as others mentioned, the line is not hot until the car is connected. The UMC also has GFCI protection built in, so my concerns would be limited.

Upstream of the UMC is a different story. An outdoor box like you have depicted (I like the Eaton one) will protect the connector, but the UMC itself is a different story. I am not really sure how waterproof it is. It has a connector from the 12” adapter to the UMC. I doubt that it rated for water immersion. I would want to protect it (also how do you keep it from being stolen?) as well.

Note that according to NEC 625 (which covers electric car charging) if you have a EV charging receptacle then it has to be GFCI protected. On a 14-50 this means a GFCI breaker which is usually over $100. For these reasons, I am a big fan of the Wall Connector. No GFCI breaker needed and it has a lot of other benefits (potentially higher amperage, longer cable, harder to steal, more robust, etc....)

I like keeping my UMC in my car always anyway, so for me the delta cost was between a second UMC and a Wall Connevtor. I ended up with a Wall Connector outside and a 14-50 in my garage just as backup or in case I park inside (uncommon). I did all the work myself, so not really much cost other than the Wall Connector.

 

[hotony13]

@reidthaler if you figure out your situation, do you mind helping me out? I'm also in NorCal and looking at ways to charge my car from home Thanks!

 

[reidthaler]

@reidthaler if you figure out your situation, do you mind helping me out? I'm also in NorCal and looking at ways to charge my car from home Thanks!

Where are you located? How to get in contact with you?

 

[hotony13]

@reidthaler I'm in San Jose, CA. Feel free to text me, I can send you a direct message on here

 

[ai4px]

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?

AH ha!!!! 240 is never more than 150 from ground! Unless you could peak to peak, but they /dont/. What is the verbiage for other instances of GFCI's? I'll have to look this up at work today.

 

[reidthaler]

So if I understand things correctly, I have two choices: one, use the 1450 connector and the cable that comes with the car, or 2) use the Wall Charger, which may have some advantages for charging and protection, and have that directly hardwired to the circuit box.

So my question is can I install a 1450 outside and use the UMC, leaving it plugged in all the time and save $500, or do I need to buy the Wall Charger if I want the convenience of outdoor charging since the car is not garaged at night.

 

[brkaus]

So my question is can I install a 1450 outside and use the UMC, leaving it plugged in all the time and save $500, or do I need to buy the Wall Charger if I want the convenience of outdoor charging since the car is not garaged at night.

Yes, you may install the 14-50 and use the portable UMC leaving it plugged in.

Considerations -

- You may want to occasionally take the UMC with you
(I ONLY take it with me when I am going to visit family, everywhere else I use the J1772 adaptor, so this is really a non-issue for me)

- UMC will charge at 32a on a 14-50. The WC will charge a Model 3 at 48A on a 60a breaker (wired appropriately)

- It looks like NEC 2017 requires a GFCI breaker (depending on your jurisdiction) on a 14-50. Those are pretty expensive, reducing the gap in cost between the 14-50 and Wall Charger.

- Security - with an RV box, you can lock the 14-50 adaptor in the box. The UMC gets locked to the car when charging, but when just hanging there not charging it could be disconnected from the 14-50 adaptor pigtail and be stolen.

- The WC has a longer cord.

There is really no correct answer. If any of the above are important to you, you can spend the extra money on a WC. Otherwise, the UMC will work fine.

 

[reidthaler]

Thanks for your great info. So the difference between the two would be length of time to charge?

I'm not concerned about theft, especially if it's behind a 1/2 wall fence. The outdoor location appeals as we don't park in the garage, and I wouldn't have to pull the cable in and out of the garage, or buy the wall charger

 

[wws]

Thanks for your great info. So the difference between the two would be length of time to charge?

The Gen 2 UMC is limited to 32 amps so that it will work safely with a 14-50 on a 40 amp circuit. With a hard-wired wall charger you can up that to 40 or 48 amps - given a 50 or 60 amp circuit.

 

[brkaus]

The Gen 2 UMC is limited to 32 amps so that it will work safely with a 14-50 on a 40 amp circuit. With a hard-wired wall charger you can up that to 40 or 48 amps - given a 50 or 60 amp circuit.

Exactly. The WC can charge approx 50% faster. Both cases will fully charge overnight. If one has circumstances that required quicker turnaround it might make a difference.

For example frequent long trips and to turnaround quickly.

 

[eprosenx]

Yes, you may install the 14-50 and use the portable UMC leaving it plugged in.

Considerations -

- You may want to occasionally take the UMC with you
(I ONLY take it with me when I am going to visit family, everywhere else I use the J1772 adaptor, so this is really a non-issue for me)

- UMC will charge at 32a on a 14-50. The WC will charge a Model 3 at 48A on a 60a breaker (wired appropriately)

- It looks like NEC 2017 requires a GFCI breaker (depending on your jurisdiction) on a 14-50. Those are pretty expensive, reducing the gap in cost between the 14-50 and Wall Charger.

- Security - with an RV box, you can lock the 14-50 adaptor in the box. The UMC gets locked to the car when charging, but when just hanging there not charging it could be disconnected from the 14-50 adaptor pigtail and be stolen.

- The WC has a longer cord.

There is really no correct answer. If any of the above are important to you, you can spend the extra money on a WC. Otherwise, the UMC will work fine.

Great post! I totally agree!

My only question: Do you think the UMC itself needs protection from the elements? Do you think were the 12" adapter connects to the UMC would be a water ingress point (as it would be hanging down below the cover to the receptacle box presumably?)

I have not studied my UMC Gen 2 that closely to see how waterproof that port is and if there are any other breather holes in the UMC.