Home charging NEMA 6-50 question

[Dayho]

We have in our garage a hold over from a previous owner. It is a NEMA 6-50 receptacle that at the breaker box is only 30 Amps and labelled welding plug.

If I get the Tesla 6-50 adapter will this be a problem with a 50 amp receptacle wired to a 30amp breaker?

 

[jerry33]

First check the wiring to see if the wiring is only 30 amp rated. If it is, you should replace the wiring. If it's actually 50 amp wiring, then you can replace the breaker.

It's possible to be okay if you manually set the Tesla to charge at 24 amps. The problem with this is that you have to check it every single time because once in a while it will revert back to the higher setting.

Personally, I wouldn't do it without upgrading the wiring and putting a new receptacle on. If you're going to that much trouble, then just install a 14-50 and be done with it.

 

[Dayho]

First check the wiring to see if the wiring is only 30 amp rated. If it is, you should replace the wiring. If it's actually 50 amp wiring, then you can replace the breaker.

It's possible to be okay if you manually set the Tesla to charge at 24 amps. The problem with this is that you have to check it every single time because once in a while it will revert back to the higher setting.

Personally, I wouldn't do it without upgrading the wiring and putting a new receptacle on. If you're going to that much trouble, then just install a 14-50 and be done with it.

Thank you. I’ll call out an electrician. Was hoping to get by on just the NEMA 6-50 adapter and hoping the car/charger was smart enough to control the AMPS to a safe level for the car on its own.

 

[Eno Deb]

This seems to be a somewhat common setup, see here for another thread:

Charging On 6-50

Some options:

- Check what gauge the wire leading to the outlet is. If it's 8 AWG or lower and you have a UMC gen 2, you can replace the 30A breaker with a 40A one and safely use the 6-50 adapter (since the gen 2 maxes out at 32A). If it's 6 AWG or lower you can put in a 50A breaker as mentioned by jerry33 above.

- If the above options don't apply and replacing the wiring is not an option, you can replace the outlet with a 6-20 and get Tesla's 6-20 adapter, or replace it with a 6-30 and get the unofficial 6-30 adapter from EVSEAdapters.

 

[Cosmacelf]

You can also just use the 6-50 adapter as is and just dial down the charging amps in the car to 24 amps. The car will remember to keep charging at that setting.

 

[camalaio]

If you want the maximum convenience (not having to set the charge current) with minimum electrical changes ($$$), see if you can get someone to swap the outlet for a NEMA 10-30. You can't do a NEMA 14-30 since you'd need an extra wire for the (not that Tesla uses it, but the plug does). Of course, you'd need to get the NEMA 10-30 adapter as well. This way, the car will only ever pull the safe maximum 80% continuous load for the 30A circuit (24A).

 

[Cosmacelf]

If you want the maximum convenience (not having to set the charge current) with minimum electrical changes ($$$), see if you can get someone to swap the outlet for a NEMA 10-30. You can't do a NEMA 14-30 since you'd need an extra wire for the (not that Tesla uses it, but the plug does). Of course, you'd need to get the NEMA 10-30 adapter as well. This way, the car will only ever pull the safe maximum 80% continuous load for the 30A circuit (24A).

I wouldn’t recommend this. First, it isn’t allowed since by code, you aren’t allowed to install new nema 10-30 outlets. Second, the nema 10-30 neutral wire would have to be connected to the bare copper ground wire that you most probably have for the 6-50 receptacle. This isn’t great for a variety of reasons. Oh, it’ll probably work, but there are corner cases where it could be dangerous which is why the electrical code has deprecated the 10-30 receptacle among other reasons.

I like the idea of swapping out the receptacle for a 6-30 and then using the EVSE 6-30 adapter available here

NEMA 6-30 Adapter for Tesla Model S/X/3 Gen 2 – EVSE Adapters

 

[M3BlueGeorgia]

You could swap the 6-50 for a 14-30, if the breaker and wiring are both at 30A. The 10-30 was superseded by 14-30 over 20 years ago.

The primary difference is the 14-30 is grounded, and the 10-30 wasn't.

 

[Cosmacelf]

You could swap the 6-50 for a 14-30, if the breaker and wiring are both at 30A. The 10-30 was superseded by 14-30 over 20 years ago.

The primary difference is the 14-30 is grounded, and the 10-30 wasn't.

You cannot do this without running an extra wire.

 

[camalaio]

I wouldn’t recommend this. First, it isn’t allowed since by code, you aren’t allowed to install new nema 10-30 outlets. Second, the nema 10-30 neutral wire would have to be connected to the bare copper ground wire that you most probably have for the 6-50 receptacle. This isn’t great for a variety of reasons. Oh, it’ll probably work, but there are corner cases where it could be dangerous which is why the electrical code has deprecated the 10-30 receptacle among other reasons.

I like the idea of swapping out the receptacle for a 6-30 and then using the EVSE 6-30 adapter available here

NEMA 6-30 Adapter for Tesla Model S/X/3 Gen 2 – EVSE Adapters

You are right of course. Don't listen to me. I checked only the Tesla first party adapters and didn't see a 6-30, good to know someone else has that covered to provide a similar and better option than what I suggested. Thanks for the correction.

 

[westie10019]

We have in our garage a hold over from a previous owner. It is a NEMA 6-50 receptacle that at the breaker box is only 30 Amps and labelled welding plug.

If I get the Tesla 6-50 adapter will this be a problem with a 50 amp receptacle wired to a 30amp breaker?

Electrical work is not a hobby, it can be dangerous if not fatal. That is why we have licensed Electricians and Licensed Electrical Engineers. I work in the Electrical Construction industry, PLEASE contact a Licensed Professinal. Don't put your life or your families life at risk. Don't listen to Jethro at Home Depot! Unfortunately I have witnessed first hand the work and results of Home Depot Electricians, belive me its not pretty! After the Fire Department and EMT leaves the home . The mess left behind is not pretty!

 

[Cosmacelf]

Electrical work is not a hobby, it can be dangerous if not fatal. That is why we have licensed Electricians and Licensed Electrical Engineers. I work in the Electrical Construction industry, PLEASE contact a Licensed Professinal. Don't put your life or your families life at risk. Don't listen to Jethro at Home Depot! Unfortunately I have witnessed first hand the work and results of Home Depot Electricians, belive me its not pretty! After the Fire Department and EMT leaves the home . The mess left behind is not pretty!

Note that the OP never asked about rewiring. He asked a simple question about using an adapter. It was everyone else who gave bad advice and then the rest of us had to step in and clear up the confusion. Threads like this can help educate people, which is no bad thing.

And there is nothing wrong with handyman electrical work as long as you learn the right way of doing it. Obviously electricians know a lot more than your typical home handyman, but that doesn’t mean a handyman can’t do a good safe job for simple work.