-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Adapter question
- Thread starter jschnepf
- Start date
eprosenx
Active Member
Should work fine! Just be sure to verify what size breaker it is on and make sure the car does not try to draw more than 80% of the breaker rating. Also, optimally a good idea to verify what size and type of wire the circuit was run with. Some welder plugs may have a 50a receptacle but not a full 50 amp capable circuit.
Ditto. I own this one. This is what I would do.
doghousePVD
My grandfather’s car
I made my 10-50 adapter. Bought a replacement stove wire with plug from Amazon and a Camco 14-50 receptacle. Worked great. So long as the breaker is either a 40A or 50A you are fine; the mobile charger won't draw more than 32A anyway. It would be highly unusual and out of code for a 10-50 outlet to have a breaker smaller than 40A.
srs5694
Active Member
Rather than a 10-50P to 14-50R adapter, you might consider buying a 10-50P to Mobile Connector adapter. This way, the temperature sensors will work to detect heating in the wall outlet, which is information that will be lost with the sort of adapter recommended earlier, since there's a length of cord between the sensors in the Mobile Connector's plug/adapter and the actual outlet. (Unfortunately, Tesla doesn't seem to make a 10-50 plug/adapter, so you've got to go with third party products, no matter how you do it.) Heating in the wall outlet should only happen if something is wrong, like undersized in-wall wiring or loose connections; but those are the sorts of conditions that can start a fire, so having the temperature sensor work is a useful safety feature. OTOH, if you need an extension cord anyhow, one that doubles as a converter between NEMA 10-50 and NEMA 14-50 won't have any drawbacks, AFAIK.
Last edited:
doghousePVD
My grandfather’s car
There is no temp sensor at the plug end of any adaptor or plug, Tesla or 3rd party. There is a convenience factor if using a Tesla 30 A adapter, eg 14-30, that it will set the charge rate to 24A (80%), but you can do that easily in the car, too.Since the mobile charger only takes 32 A no matter what is plugged in, it doesn't matter if a 6-50 or 10-50 connected via a 14-50.
Technically a 10-50 adaptor is out of code since there is no ground, only a neutral. It could in unusual circumstances trip the mobile charger and refuse to charge. There isn't really any danger, it just won't work (rarely) with a Tesla that requires a ground. I haven't heard of any real world failures of this sort.
srs5694
Active Member
According to this article describing the innards of the Gen1 and Gen2 Mobile Connectors, the Gen2 unit does include temperature sensors on the wall plug end. The description of the third-party Mobile Connector plug/adapter that I recommended (note: I initially provided the wrong URL, but I corrected it) includes the following: "For your safety, this adapter has an internal circuit that monitors the plug temperature."
doghousePVD
My grandfather’s car
eprosenx
Active Member
10-50 receptacles are allowed if they were “grandfathered” in from an old install. You can’t install new ones.
Tesla’s have a factory adapter for 10-30. They simply use the neutral as if it is a ground. It is mostly the same anyway (connected to the same place). The same would hold true with a 10-50 as well, so the Tesla adapter would not trip out. All Tesla’s will check to make sure ground is good though.
Tesla using the neutral as a ground is actually way safer than using an oven on an old 3 wire circuit. In the case of the oven, the chassis of the oven is tied to neutral which is slightly sketch.
Though now that I think of it, I wonder if the chassis of the car gets tied to the ground (or neutral in this case) while charging? I would not be surprised if it is isolated.
I also have a 10-50P in my garage.
Anyone with experience in this:
AC Works 50 AMP 3-Prong NEMA 10-50P to 14-50R
Anyone with experience in this:
AC Works 50 AMP 3-Prong NEMA 10-50P to 14-50R
eprosenx
Active Member
That would work fine, but first a question:
Is that receptacle used for anything else? If not, I would simply replace it with a 6-50 and buy the proper Tesla adapter from Tesla for $35 and call it a day. As long as it is not fed from a sub panel, no work has to be done in the electrical box itself.
It is safer to use the Tesla adapters with thermal monitors in them than it is to use a third party adapter. Also, 10-50 is a super ancient receptacle type that kind of needs to die (it has no ground, but in your case the Tesla uses the neutral as the ground).
I would of course verify the breaker size it is on and what the wire type / size is (aluminum or copper) to validate its ampacity before trusting it.
Good luck!
It is not being used for anything else. It used to be connected to the dryer. If the panel descriptions are accurate, it's hooked to a 40 amp breaker. I have a panel outside with a single 100 amp breaker, and this is connected to a panel inside. Not sure if that makes it a sub panel?
I have read some things online about changing to a different receptacle, may I know:
1. Is it 'plug and play' with the new receptacle? Do I just use the same wires and attach it to the 6-50?
2. Why 6-50 and not 14-50?
3. What about the ground wire that's missing from the 10-50?
4. Why is this 50 amp receptacle wired to a 40 amp breaker?
5. How can I verify the wires? Look at the breaker connected wires?
Thanks for your help.
To do a proper conversion of a 10-50 to a 6-50, you'd have to modify the circuit inside the electrical panel it is fed from. You'd move the neutral wire to the ground bar from the neutral bar. Then you could replace the 10-50 receptacle with a 6-50 one.
You would not be able to install a 14-50 since the 14-50 requires four wires and you only have three for the 10-50.
It is fairly common to have 50 amp rated receptacles connected to 40 amp breakers since our system does not have 40 amp receptacles, only 30 amp and 50 amp ones. Tesla's adapters only draw 32A from their 50A adapters, so they work fine with 40A breakers.
I'm not sure what you mean by verifying the wires, but if you mean making sure the receptacle is attached to the breaker you think it is attached to, then get a volt/ohm meter. Turn the volt meter to AC, stick the probes into the receptacle, make sure you see about 240V. Then flip the breaker off, and go back and make sure the reading is now 0. You can do the same thing with a small inductive live circuit tester. Its those small things that you place near a receptacle and when you press the button, it'll flash and/or beep if the circuit is live.
Converting to a new 6-50 receptacle is the best way to do this since you you'll get a new receptacle, and get to use a Tesla adapter directly. It isn't unusual for old dryer receptacles to not be in the best shape.
You would not be able to install a 14-50 since the 14-50 requires four wires and you only have three for the 10-50.
It is fairly common to have 50 amp rated receptacles connected to 40 amp breakers since our system does not have 40 amp receptacles, only 30 amp and 50 amp ones. Tesla's adapters only draw 32A from their 50A adapters, so they work fine with 40A breakers.
I'm not sure what you mean by verifying the wires, but if you mean making sure the receptacle is attached to the breaker you think it is attached to, then get a volt/ohm meter. Turn the volt meter to AC, stick the probes into the receptacle, make sure you see about 240V. Then flip the breaker off, and go back and make sure the reading is now 0. You can do the same thing with a small inductive live circuit tester. Its those small things that you place near a receptacle and when you press the button, it'll flash and/or beep if the circuit is live.
Converting to a new 6-50 receptacle is the best way to do this since you you'll get a new receptacle, and get to use a Tesla adapter directly. It isn't unusual for old dryer receptacles to not be in the best shape.
Thanks @eprosenx @Cosmacelf
I will find someone to switch my receptacle to 6-50 and switch the neutral to ground on the sub panel for this circuit.
eprosenx
Active Member
You are asking the right questions!
If your outside panel has a 100a main breaker then yes, it probably is the single point in your system where neutral and ground should be bonded together. This makes your inside panel a sub panel.
The reason I asked is because if the panel the dryer circuit is in is a subpanel then you would need to move the neutral wire over to the ground bus in the panel when converting from a 10-50 to a 6-50 receptacle. If it is the main panel then the neutral and ground bus are functionally the same and so it would not need to be moved.
So since we are assuming this is a subpanel, it is technically not plug-and-play. If you just swapped the receptacle out it would work fine, but if a neutral wire from the sub panel to the main panel came loose at a later date it could cause a very dangerous condition.
If you have a four wire conductor (two hots a neutral and a ground) then I would do a 14-50 (since it is more common), but my best guess is that you only have a three conductor wire. The good news is that for EV charging there is no need for the fourth conductor, so a 6-50 works great.
As @Cosmacelf mentioned, it is common to find 40a circuits connected to 50a receptacles. As long as you are using a UMC Gen 2 you will be fine since it only draws 32a continuous (which only needs a 40a circuit).
It is critical to verify the wire type/gauge though since I also often see the wrong size breaker on things. It could be only 10 gauge wire or something!
To verify the wires you could look in the breaker panel or in the receptacle box (or better yet, both to make sure nobody changed wire type in the middle of the circuit).
Good luck and please report back! It sounds like you are on the right track!
Feel free to post pictures of your panels and the receptacles if you have any questions!
Similar threads
- Question
