I have learned the following in preparation for a trip to Newfoundland in our Model 3 long range. We need to be able to charge from as many sources as possible, but want to keep the number of cables and adapters down. The long range car can take 48A at 240V, the UMC gen 2 can charge at 32A. The UMC uses resistors in the supplied adapters to set the charging rate so its not easy to make an adapter on your own to fit the UMC socket, so its easier to set the charge rate limit on the car screen.
I have chosen to use a 30A, 50 foot RV extension cord. A 50Amp cord would be heavier and more expensive. With the Gen2 UMC the car can only take 32A max anyway. If you do buy a 30A cords or adapters, do not get ones with lights as they will be designed only for 120V not 240V. RV parks have 50A outlets (240VAC) of which only about 40A should be used and 30A outlets (120VAC) of which only about 24A should be used.
If you buy a normal 50A male to 30A female RV adapter you will only get 120VAC (one hot and one neutral) and the car will not charge with the Tesla supplied 50A UMC adapter (as the hot and neutral are not connected to the 2 hot pins on the 50A connector that the 14-50UMC is looking for). If you buy a special 50A male to 30A female adapter marked for Tesla (amazon or EVSE chargers) it will work as they will be wired to the 2 hot pins but this adapter can't be used for RVs as it will be twice the voltage the RV is expecting.
Oven outlets (NEMA 14-50) and dryer outlets (NEMA 14-30) are the same shape and size except for the neutral pin (flat blade in the centre). To save on connectors since the 14-50 UMC adapter does not use the neutral pin, removing it allows a male plug 50A to fit in both Oven and Dryer sockets.
Lowes sells the male 14-50 replacement head plug which has two different neutral pins which can be switched for ovens (straight neutral) or dryers (L shape neutral) or left off for less than $20.
I will be setting 24A max charge rate using the extension cord which should give about 37km/hour or 23 miles/hour at 240VAC and half this at 120VAC.
Here are two non standard adapters. The first converts the 240VAC from a oven or dryer to NEMA 14-30, for attachment to a 14-30 extension cord. The second converts it back to 14-50 for the UMC.
Then also regular adapters can be purchased for use with 120VAC. So only one extension cord can be carried.
I hope this information helps.
On Amazon
Conntek 14364 RV 30-Amp STW 10/3 Durable Extension Cord with Straight Blade, 50-Feet
Camco 55353 50 AMP Female Replacement Receptacle
Camco 55175 RV 18-Inch Power Grip Dogbone Electrical Adapter with Handle
I have chosen to use a 30A, 50 foot RV extension cord. A 50Amp cord would be heavier and more expensive. With the Gen2 UMC the car can only take 32A max anyway. If you do buy a 30A cords or adapters, do not get ones with lights as they will be designed only for 120V not 240V. RV parks have 50A outlets (240VAC) of which only about 40A should be used and 30A outlets (120VAC) of which only about 24A should be used.
If you buy a normal 50A male to 30A female RV adapter you will only get 120VAC (one hot and one neutral) and the car will not charge with the Tesla supplied 50A UMC adapter (as the hot and neutral are not connected to the 2 hot pins on the 50A connector that the 14-50UMC is looking for). If you buy a special 50A male to 30A female adapter marked for Tesla (amazon or EVSE chargers) it will work as they will be wired to the 2 hot pins but this adapter can't be used for RVs as it will be twice the voltage the RV is expecting.
Oven outlets (NEMA 14-50) and dryer outlets (NEMA 14-30) are the same shape and size except for the neutral pin (flat blade in the centre). To save on connectors since the 14-50 UMC adapter does not use the neutral pin, removing it allows a male plug 50A to fit in both Oven and Dryer sockets.
Lowes sells the male 14-50 replacement head plug which has two different neutral pins which can be switched for ovens (straight neutral) or dryers (L shape neutral) or left off for less than $20.
I will be setting 24A max charge rate using the extension cord which should give about 37km/hour or 23 miles/hour at 240VAC and half this at 120VAC.
Here are two non standard adapters. The first converts the 240VAC from a oven or dryer to NEMA 14-30, for attachment to a 14-30 extension cord. The second converts it back to 14-50 for the UMC.
Then also regular adapters can be purchased for use with 120VAC. So only one extension cord can be carried.
I hope this information helps.
On Amazon
Conntek 14364 RV 30-Amp STW 10/3 Durable Extension Cord with Straight Blade, 50-Feet
Camco 55353 50 AMP Female Replacement Receptacle
Camco 55175 RV 18-Inch Power Grip Dogbone Electrical Adapter with Handle