Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Charging Outlet Question

This site may earn commission on affiliate links.
I have a NEMA 6-50 outlet in my garage for my welder. I'm planning to use that outlet with the UMC to charge my car. I could cut off the fourth pin of the 14-50 plug on the UMC, and it appears that would fit the 6-50 outlet? Will that work instead of using an adapter?

Thanks
I may be wrong but the plug configuration doesn't look the same.
nema 14-50.JPG
 
I am not an electrician, but I have made many adapters. You can go to Home Depot, et al, and pick up receptacles and plugs and a few feet of wire and make an adapter, or wire your outlet as a 14-50 and make an adapter for your welder. Make sure you use adequate wire size, #6, for 50 amp (40 amp continuous).

Cutting off the grounding pin on the UMC sounds like the wrong way to do this. Most electrical devices check for voltage and ground, and when making an adapter, you need to make sure that both ground and neg wires are hooked up to the ground of the circuit breaker box. If you cut off the pin, that won't happen. And then your UMC probably won't work.

Since you will be using the outlet to charge more than weld, I would make the 14-50 the outlet of choice, and then when you weld, you can plug that adapter in, leaving it on your welder cord.

There are several 50 amp plug types. You might make several adapters. They are relatively easy to do. Then you can charge where ever you might be.
 
FYI, I assume the OP is asking about the Roadster, not the Model S.

Cutting off the grounding pin on the UMC sounds like the wrong way to do this.
It's the unused neutral blade on the NEMA 14-50 that he'd cut off, not the ground pin. That would help for a NEMA 14-30 outlet, but not with a NEMA 6-50.

UMC adapters can be had from Tesla for $100.
Universal Adapters - Available in North America Only (charging) Tesla Motors
Assuming it's in stock, that's your simplest solution. (You are talking about the UMC, right?? And not the old MC240?)

You could convert the outlet the NEMA 6-50 outlet to a NEMA 14-50, but you'd have to make sure a neutral line is included in the wiring. It might not be.
 
This is in the Roadster section... I removed (not cut off) the neutral pin on the UMC quite easily. Having opened the 14-50 pigtail, it will be trivial to remove the 14-50 plug and put a 6-50 plug on it. Although if Tesla is truly not making the 6-50 anymore, I would recommend building your own pigtail or ordering an extra 14-50 and replacing the plug.
 
Isn't Tesla offering a 6-50 end for the UMC? Charging Model S | Tesla Motors

I think they do offer the adapter but I was thinking that for something that is being used all the time I would prefer to avoid using an adapter. It reminds me of using those adapters that would allow you to use a grounded plug on the old outlets that had no ground. Well, that and the $100 price of the Tesla item. :biggrin:

- - - Updated - - -

I may be wrong but the plug configuration doesn't look the same.View attachment 11792

Hmmm, you may be right. I'll run up to the hardware store to take a look.

Thanks

- - - Updated - - -

I am not an electrician, but I have made many adapters. You can go to Home Depot, et al, and pick up receptacles and plugs and a few feet of wire and make an adapter, or wire your outlet as a 14-50 and make an adapter for your welder. Make sure you use adequate wire size, #6, for 50 amp (40 amp continuous).

Cutting off the grounding pin on the UMC sounds like the wrong way to do this. Most electrical devices check for voltage and ground, and when making an adapter, you need to make sure that both ground and neg wires are hooked up to the ground of the circuit breaker box. If you cut off the pin, that won't happen. And then your UMC probably won't work.

Since you will be using the outlet to charge more than weld, I would make the 14-50 the outlet of choice, and then when you weld, you can plug that adapter in, leaving it on your welder cord.

There are several 50 amp plug types. You might make several adapters. They are relatively easy to do. Then you can charge where ever you might be.

That all makes a lot of sense.
Thanks

- - - Updated - - -

FYI, I assume the OP is asking about the Roadster, not the Model S.


It's the unused neutral blade on the NEMA 14-50 that he'd cut off, not the ground pin. That would help for a NEMA 14-30 outlet, but not with a NEMA 6-50.

UMC adapters can be had from Tesla for $100.
Universal Adapters - Available in North America Only (charging) Tesla Motors
Assuming it's in stock, that's your simplest solution. (You are talking about the UMC, right?? And not the old MC240?)

You could convert the outlet the NEMA 6-50 outlet to a NEMA 14-50, but you'd have to make sure a neutral line is included in the wiring. It might not be.

I thought the UMC and the MC240 were the same thing, apparently I thought wrong. I probably will get the MC240 with the car.

Thanks

- - - Updated - - -

This is in the Roadster section... I removed (not cut off) the neutral pin on the UMC quite easily. Having opened the 14-50 pigtail, it will be trivial to remove the 14-50 plug and put a 6-50 plug on it. Although if Tesla is truly not making the 6-50 anymore, I would recommend building your own pigtail or ordering an extra 14-50 and replacing the plug.

Thanks
 
I have both the 6-50 and 14-50 pigtails. They're definitely not interchangeable - the blades on the 6-50 are spaced closer together than the 14-50 blades. I'd just get the 6-50 from Tesla. It's a replacement pigtail, not an adapter for a 14-50, so it's good for regular use.
 
Sorry all, have had Model S on the brain lately and using the "New Posts" feature didn't realize it was in the Roadster section.

But Doug and I are right, why don't you just buy the 6-50 adapter from Tesla?

If I go that route,:biggrin: I'll probably just make up my own. It would kill me to pay $100 for something I can probably make for $20. :biggrin:

Thanks

- - - Updated - - -

I have both the 6-50 and 14-50 pigtails. They're definitely not interchangeable - the blades on the 6-50 are spaced closer together than the 14-50 blades. I'd just get the 6-50 from Tesla. It's a replacement pigtail, not an adapter for a 14-50, so it's good for regular use.

Thanks
 
So it looks like the MC240 has a 30 amp rating where the UMC has a 40 amp rating. Is there a way to upgrade the MC240 to 40 amps?

Interesting, when my MC240 was first delivered (with the car), it would happily charge at 40 Amps. But then there was the software upgrade for the car to work with J1772s, and the MC240 stopped working with it. They loaned me one of the newer charger cables, for a couple of months, and when the MC240 came back it was limited to 30 Amps.