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Charging from NEMA 6-20 using NEMA 5-20 Adapter

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Hello,

I'm exploring my options. I'm converting a 110v outlet wired with 12/2 gauge (110v/20A) to a 240v. Since the maximum possible current is 20A with this 12 gauge is 20A, my only option is to replace it with NEMA 6-20 (240v/20A).

Tesla doesn't sell 6-20 adapter, but it does sell 5-20 adapter. What would happen if I used the 5-20 adapter? Does the internal charger adjust itself depending on the installed adapter?

I'm a bit confused... I noticed some people created their own adapter from 6-20 -> 14-40 but I'm not sure how the internal charger would know that the maximum available current is 20A (or 16A continuous) to avoid overloading the breaker and triggering it.

Please advice.


Thanks!
 
It will work no problem. It will just charge at 16 amps at 240v.

As most hotels/motels use a 6-20 for the Air conditioner/heater, I made a adapter that converts 6-20 to 5-20, then plug in the 5-20 Tesla adapter, the car then charges at the 16amps (remember, 16 amps sustained current from a 20 amp outlet) at 240v. Works great!
Cost about $8 to make the adapter. I used a 6-20 plug, then 4 inches of Romex (I had a ton laying around), then that goes to a 5-20 extension cord end.
 
This will work, but YOU MUST make sure that the 120V outlet you are converting IS NOT connected to any other 120V outlet. If it is, then somewhere down the road someone will plug into the 120V outlet and get 240V out of it and fry whatever they've plugged into it.

It is rare to have a single 120V outlet be on a breaker all by itself, so do be careful here.

Once you have a NEMA 6-20 outlet, then yes, using Tesla's NEMA 5-20 adapter and then a 5-20 to 6-20 pigtail will work great. You won't have to set any amperage settings in the car since the Tesla 5-20 adapter will draw the correct amount for a 20A circuit, and it doesn't care or know if it has 120V or 240V going through it (the UMC handles with 120V or 240V, of course).

Here are some products you can use:

Female 5-20 receptacle:
http://www.amazon.com/gp/product/B004285E6Q/ref=oh_details_o09_s00_i00?ie=UTF8&psc=1

NEMA 6-20 cord:
http://www.amazon.com/gp/product/B003OQVGNW/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
Just chop off the female receptacle end of the cord and wire it into the NEMA 5-20.
 
It will work no problem. It will just charge at 16 amps at 240v.

As most hotels/motels use a 6-20 for the Air conditioner/heater, I made a adapter that converts 6-20 to 5-20, then plug in the 5-20 Tesla adapter, the car then charges at the 16amps (remember, 16 amps sustained current from a 20 amp outlet) at 240v. Works great!

+1
One my favorite well labeled "Warning 230V", "Tesla ONLY" custom adapters used in conjunction with an unadulterated, molded ended 5-20 12AWG extension cord along with the factory Tesla UMC 5-20 adapter that requires no owner/operator amp adjustment.

As the previous electrical maven poster stated, first insure that it is the sole receptacle on that branch circuit.

I always mark the white neutral (previous) wire in both the receptacle box and load center with black electrical tape or black magic marker thus designating it as a hot conductor.
 
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Thanks, @Cosmacelf!

+1
One my favorite well labeled "Warning 230V", "Tesla ONLY" custom adapters used in conjunction with an unadulterated, molded ended 5-20 12AWG extension cord along with the factory Tesla UMC 5-20 adapter that requires no owner/operator amp adjustment.

As the previous electrical maven poster stated, first insure that it is the sole receptacle on that branch circuit.

I always mark the white neutral (previous) wire in both the receptacle box and load center with black electrical tape or black magic marker thus designating it as a hot conductor.

Yeah, thanks for pointing that out. I will use a tape for sure.
 
OH, I just realized that you were going to convert the circuit to 240V at the breaker box, but leave the NEMA 5-20 receptacle there and then just plug the Tesla into it with a 5-20 adapter? This will work, and a lot less trouble than replacing the receptacle with a NEMA 6-20 and making adapters. But if you ever got hit by a truck, and next poor guy who tried to use that receptacle would get quite a surprise. If you do this (not recommended), put up a sign on the exterior of the NEMA 5-20 receptacle making sure people know it is 240V.
 
OH, I just realized that you were going to convert the circuit to 240V at the breaker box, but leave the NEMA 5-20 receptacle there and then just plug the Tesla into it with a 5-20 adapter? This will work, and a lot less trouble than replacing the receptacle with a NEMA 6-20 and making adapters.

YIKES! ! I hope the OP ISN'T converting the existing NEMA 5-20 receptacle to deliver 240V!!! Certainly much easier like the electrical maven just stated, BUT PLEEZE replace the 5-20 receptacle with the proper code adhering NEMA 6-20 receptacle and take the time to make the $30 well labeled custom adapter.
 
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YIKES! ! I hope the OP ISN'T converting the existing NEMA 5-20 receptacle to deliver 240V!!! Certainly much easier like the electrical maven just stated, BUT PLEEZE replace the 5-20 receptacle with the proper code adhering NEMA 6-20 receptacle and take the time to make a well labeled custom adapter.

LOL. No, I'm actually converting a 5-15 to 6-20. And yes, I will be putting a 6-20 receptacle and adding a label to that (just in case). I was actually looking at the custom adapter minutes ago; i think it will be my little project tomorrow.

Thanks everyone for all the info. I'm sure many people will benefit from it.
 
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Here is a pic of the $30 adapter from the parts Cosmacelf recommended.
 

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I bought the 6-20p to 5-20R adapter from EVSEADAPTERS.COM and trying to charge using it with the Tesla 5-20P adapter and UMC. Unfortunately everytime the charge cycle starts it seems to dial up the Amperage to 48A and it trips the 20amp breaker.

I tried to manually dial down the amps drawn in the charge settings on the main screen to 5A before plugging it in, but it still seems to be happening.

Any ideas from anyone? I'm relegated to slow 5-15 110v charging until this can be solved :(
 
I bought the 6-20p to 5-20R adapter from EVSEADAPTERS.COM and trying to charge using it with the Tesla 5-20P adapter and UMC. Unfortunately everytime the charge cycle starts it seems to dial up the Amperage to 48A and it trips the 20amp breaker.

I tried to manually dial down the amps drawn in the charge settings on the main screen to 5A before plugging it in, but it still seems to be happening.

Any ideas from anyone? I'm relegated to slow 5-15 110v charging until this can be solved :(
That's very strange. Someone just returned my similar 6-20 to 5-20 after using it on a trip and said it worked just fine. Have you ever used your UMC 5-20 adapter by itself in a 120V 20A outlet? I wonder if that is defective. Also has your car set the amps wrong when using a 14-50?