Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
  • Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
  • The final cut of TMC Podcast #27 is available now with topics time-stamped. We discussed: Consolidation in LiDAR manufacturers; Volvo EX90 shipping with LiDAR; FSD Beta Full Release in N.A.; FSD detecting autopilot cheats, Gwen Shotwell directly overseeing SpaceX Starship; and more. You can watch it now on YouTube. We should have it published to podcast networks shortly.

What extension cable should I use (50AMP or 30AMP) NEMA 14-30 and NEMA 14-50?

I have two places that I visit and trying to figure out the EV charging setup. One is in Canada. It has a dryer outlet 14-30R and other in the USA has NEMA 14-50 type of plug--not sure of the Amperage. I have a Tesla adapter for NEMA 14-50. Ideally, I want to use one extension cord for both setups.
I have bought a NEMA 14-30P to 14-50R adapter. The question is that what specification for the extension cord will work, or will I need two extension cords with two adapters?
I am getting a reasonable price ($70) for an extension cord with 30 Amp 10AWG/3c 36 FT with NEMA 14-50 male and female plugs. Will this work for both? I understand it will deliver less power and more charging time for NEMA 14-50 location. The second option is that 50A, 8AWG cord with NEAM 14-50 male and female, which costs $135.

Screen Shot 2022-08-31 at 1.00.06 PM.png
Screen Shot 2022-08-31 at 12.59.15 PM.png

Screen Shot 2022-08-31 at 12.48.42 PM.png
I went with Lectron 20 foot extension to Tesla native cable. It avoided me to carry three separate extension cords (5-15, 14-30 and 14-50) as suggested above in this discussion by various members. It is little pricey. With coupons etc. you can get it for $200 but still cheaper than buying 3 or 4 extension cords, and the undesirability of carrying those fat cables with you everywhere you go.

So now I have Tesla adapters of 5 types and one extension cord seems to work for all of them.

Lectron is making Tesla adapters of all sorts for a while , so I guess they...
Absolutely NOT safe. If you have a 14-30 outlet and connect it to a 14-50 extension cord, you need to convert back to 14-30 on the other side and use the 14-30 plug adapter for your mobile connector, so that it's hardware limited to 24A. If you're plugging a 14-30 extension cord into a 14-30 outlet, you should not be converting to a 14-50 before connecting to your mobile connector, you should use the proper adapter (in this case, a 14-30 adapter). Using the car to limit to 24A while the EVSE advertises 32A on a 30A outlet is not safe and could overdraw if the car has a software regression bug (and Tesla is always having those).
If you had quoted a different post this would be a good reply. However poster was using 30amp cord and 30 amp tesla adapter though.
  • Informative
Reactions: Rocky_H
Upvote 0
I also wanted to buy two and asked the support and was told that you cannot combine but she did not seem very knowledgeable.
Please confirm if you can combine and it works.
Bought 3 of them and have now been using them. Hooked up to a wall charger at 40amps (50amp breaker) all 3 of them work fine combined! I'd say about 1 volt drop on each one, normally I get about 245 Volts and with all three it's around 242 volts. Much less voltage drop than I'd expect. Connections seems very secure and cable is much thicker than gen3 wall connector so appears good quality.

I now can have Tesla UMC plug at recepticle which monitors the temperature. Previously I had a 14-50 extension cord with all sorts of different adapters. Now I can get rid of almost all of those and just use my UMC adaptors with this Tesla extension cord(s). Only adapters I have that I might carry are 10-50, L14-30 as Tesla doesn't make an adapter. I bought the evse tt30 UMC one.

Super excited to use this setup.
  • Like
Reactions: wadood
Upvote 0
This is probably the best solution but maaan... pretty pricey.

Yeah its probably not an ideal use of money. Especially as more chargers pop up and the new CCS adapter being available. I end up doing camping and other activities in remote areas where the flexibility to plug into any dryer/stove/rv outlets is a huge benefit. Plus I plan to have a Tesla over a decade.

However the 14-50 extension cords and additional adapters are many hundreds of dollars as well, so its only the difference in cost needed if someone were to jump into buying.

If a company comes up with a bigger extension such as a 40'+ tesla extension then it would probably be ideal to have one of those and a 20' extension instead of the three 20' ones I have.

These are the only Tesla extension cables I have seen so I jumped at buying up a few from a reputable company because I was skeptical they would be available.
  • Like
Reactions: Gaige and wadood
Upvote 0

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.