Q: How does Tesla respond to NEMA 14-50 questions?
A: While an existing NEMA 14-50 outlet will work to charge the car, you would need to purchase the $35 adapter from Tesla to make it work, they are not provided with the vehicle.
Tesla does not recommend installing a new NEMA 14-50 outlet to charge your car. Installing a Tesla Wall Connector is the recommendation, and it is for a number of reasons.
First off, the electrical code has changed to require all new NEMA 14-50 outlets be installed on GFCI breakers. The Tesla already has one on-board to protect itself, and if you have two GFCIs on the same circuit, they tend to trip each other, making for a very unreliable charging setup. Not all building departments are enforcing this code requirement, though, so you’ll have to check with your electrician if you might be able to get away with a standard breaker on a new NEMA 14-50 outlet.
Second, the maximum charge rate for a Model S on a NEMA 14-50 outlet is 23 miles of charge per hour. The Wall Connector on a 60amp circuit will give you 34 miles of charge per hour, so 50% faster charging.
Third, the reliability of charging on a NEMA 14-50 outlet is limited by design and quality of the outlet your electrician buys. There is a $15 (Leviton brand) residential grade NEMA 14-50 outlet sold at Home Depot that is not sufficient to support daily vehicle charging. The Leviton outlet has fiberglass insulators that tend to melt out after a few months of vehicle charging. The outlets are not designed specifically for EV charging; they are designed for plugging in RVs and range ovens. Ranges will pull max power once in a while when we roast a turkey, but EV charging will be pulling maximum amperage for hours on end every night. For this heavy use, we recommend an industrial grade NEMA 14-50 outlet, by one of these three brands: Hubbell, Bryant, or Cooper. These use glass or ceramic insulators and should last 3-5 years before they, too, eventually need to be replaced. At $50 – $100, they are not cheap.
Fourth, installing a Tesla Wall Connector lets you keep the mobile connector that comes with the car in the car. If you are using the cord that comes with the car to charge at your home every night, you will need to unplug it and take it with you every time you travel, which is time consuming and will wear out your plug faster. Most owners in this situation end up purchasing a second Mobile Connector Bundle to keep in the car as a backup, which is ~$300. Many folks expect to save some money by installing the NEMA 14-50 outlet instead of the Wall Connector, but that usually doesn’t end up being the case in the long run.
So for faster charging, a more reliable charging setup, a future-proofed design (the Gen3 Wall Connector gets OTA firmware updates), and a better looking unit, the Tesla Wall Connector is our only recommendation. I have attached the Gen3 Wall Connector installation guide as a reference.
I hope this helps!
Jonas Clausen | Tesla Installation Project Manager
47700 Kato Rd. | Fremont, CA 94538
Shared with Jonas Clausen’s permission.
