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48 amps through a 50 amp NEMA 14-50?

Edit - Mods, if this is in the wrong place, please move.

Hi everyone. Normally, we plan for 80% utilization for a given circuit. If you have a 40A circuit, you can charge at 32A for example. 50A can charge at 40A, and 60A can charge at 48A. You get the idea.

I have a dedicated 60A circuit running 5 feet with #6 wire. It can easily handle the max charge rate of my model Y at 48A. This issues is that I have a 50A 14-50 plug in line.

Now, I know to pass code, I can swap the 60A breaker for a 50A and the problem is solved. This is what I would do if I was selling the house or had any concern of anyone plugging in a load greater than 50A. Since I'm the only one using it and I know they only load will ever be my car and it tops out at 48A and the plug is rated at 50A, do you think its OK to leave it there?

I have a Tesla Wall connector and it is currently set to charge at 40A and I'm wondering about cranking it up to 48A. Thoughts?
 

Rocky_H

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Feb 19, 2015
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Boise, ID
No.
1. It is a code violation
2. Sure, you say if/when you sell the house, you'll change it. What if you die suddenly, and the house gets sold without a chance for you to change that? Then there is a dangerous, unsafe, code violating outlet left there to catch someone else.
3. So it's a wall connector? You added a pigtail cord with a 14-50 plug on it, in violation of the manufacturer's installation instructions? Another code violation.
4. The ratings of the outlets are I think about the same as the wiring. 50A for short term cycling loads, not for long term permanent ones.
5. Cord and plug is yet another set of not tight touching contacts, (unlike hardwiring) which is yet another place where things can get loose and have a not good connection, which can become resistive and a hot spot and a fire risk. That is exactly the place where I WOULD NOT recommend trying to push the current extra high.
 
NEMA 14-60P to 14-50R, 60A to 50A RV Adapter – EVSE Adapters

This claims to be good for a 60A plug and 50A continuous for a NEMA14-50 socket.
I can't read the fine print on the plug in the pic, whether it is UL approved for the USA. The "Contact us" has a USA address so the implication is that it's legal approved. YMMV.

What I did for my Gen2 charger was put a power cord on it with a NEMA 14-50 plug, so I could use the charger (limited to 40A) or the mobile charger (Max 32A). Can you not find a power cord and plug to attach your charger to plug into a 60A socket?

(You have a charger that's good for 48A? What sort of charger?)
 
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Rocky_H

Well-Known Member
Feb 19, 2015
7,853
9,882
Boise, ID
NEMA 14-60P to 14-50R, 60A to 50A RV Adapter – EVSE Adapters

This claims to be good for a 60A plug and 50A continuous for a NEMA14-50 socket.
I can't read the fine print on the plug in the pic, whether it is UL approved for the USA. The "Contact us" has a USA address so the implication is that it's legal approved. YMMV.
Ugh. I love EVSEAdapters, but that is really irresponsible of them to suggest that it can be used for 50A continuous. Since it has a 14-50 receptacle on one end, you really shouldn't be overdrawing it like that, which is what continuous 50A would be doing. Even IF you were to allow that this is plugging into a 60A outlet type, continuous loads STILL should not be above 48A for that!!

And he doesn't have a 14-60 receptacle in the wall anyway. And this would be worse relating to my point 5 above if this were to go from a 14-60 outlet in the wall, through this adapter pigtail, to his attached cord, and into his wall connector. That is getting even more spring tension plug connections, for even more weak points in the chain. Not good.

Just being in the USA certainly doesn't imply that it's UL approved, and I would doubt that something like this is. They make a lot of other adapter cables that in no way could ever be UL approved.

What I did for my Gen2 charger was put a power cord on it with a NEMA 14-50 plug, so I could use the charger (limited to 40A) or the mobile charger (Max 32A). Can you not find a power cord and plug to attach your charger to plug into a 60A socket?

(You have a charger that's good for 48A? What sort of charger?)
He already explained all that. He has a wall connector that has a separate 14-50 cord attached.
 
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This is what my install looks like. I swapped out the 60A for a 50A breaker tonight and will leave the Wall connector set to 40A. You can ignore the mess of wires at the bottom of the panel box. That will connect to a separate 20A breaker to run a line to my workshop but I wanted to get everything into the panel box at the same time as I was working on the EVSE.
 

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Good idea - 40A, 48A - what's the difference? My 40A charges my 3 at 59km/hr (39mi/hr) which means I could go from 0 to 100% at just over 8 hours, theoretically. In real life, going to 80% it's a rare day (overnight) when I need more than 4 hours, and usually only 2 or 3. (More in winter) I have set charging to start at 1AM and I don't recall ever interrupting charging to leave.

And If I come home and am worried about an evening trip, I can add a bit for an hour or two. If I could do 48A then I'd maybe charge about 12km/hr more. (8mi/hr). Hardly matters. The biggest change in driving mindset is starting each day with a "full tank".

Ugh. I love EVSEAdapters, but that is really irresponsible of them to suggest that it can be used for 50A continuous. Since it has a 14-50 receptacle on one end, you really shouldn't be overdrawing it like that, which is what continuous 50A would be doing. Even IF you were to allow that this is plugging into a 60A outlet type, continuous loads STILL should not be above 48A for that!!
Yeah, thanks - that's why my question. I'm surprised it's legal to sell (or import) electrical devices that don't have the certification, but then you're talking about a country where one state's whole electrical system can't even handle the snowstorms that happen every 10 years.
 

Rocky_H

Well-Known Member
Feb 19, 2015
7,853
9,882
Boise, ID
Yeah, thanks - that's why my question. I'm surprised it's legal to sell (or import) electrical devices that don't have the certification,
Well, it doesn't seem that unusual that a lot of products are sold that are "Use at your own risk", but that's what the certification is there for. They can't announce that it has it if it doesn't have it. That is proof that it has been checked and tested to certain standards, and people might pay more for certain types of products that do have that certification.

But we're kind of in a niche of products that just can't be UL certified. Adapter pigtails that make all kinds of things fit into other things they weren't intended for is not something that is going to be approved, but it's the kind of thing we do sometimes need in the EV world with some places lacking enough "official" type of charging infrastructure. And being able to buy really well built ones from EVSEAdapters is a hell of a lot better than DIY.
 
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Rocky_H

Well-Known Member
Feb 19, 2015
7,853
9,882
Boise, ID
Why would you say this is a violation?
Because people have been DIY adding cords to them in violation of the install instructions for many years. That's what I thought was going on with yours.
My wall charger came with a 14-50 plug on it from the factory.
OK, I did not know you had gotten one of those. They only sold those for a very short time--less than a year. So that's why I was not expecting that you had one of the official supported ones.
You can order it with or without.
No, they've been discontinued for quite a while now.
 
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