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Bag of Spare Adapters?

TM now has several adapters for sale. Is there much benefit to buying some or all of them to have on hand when out on the road?

@jat - I am using the NEMA TT-30P RV Plug to 14-50R Adapter, made expressly for the Model S.

I believe the first version of this adapter did not work for the reasons you cite, but several people on this forum state that the revised adapter works fine.

Thanks jat and shop for your input. I will try testing this configuration before I need to use it.

@DouglasR - that should work fine then

Speaking of kids and cords and lamp plugs, one day many moons ago my 4-yr old decided to see if my pliers/wire cutter/stripper would remove the plug from a lamp cord by cutting the wire. While it was attached, and the lamp plugged in. The bang it made vaporizing about ¼-½"sq. of the cutting edges was quite dramatic. The handles were rubberized, so no fatalities occurred.

BrianH-I did the exact same thing as a kid with a pair of insulated diagonal cutters. Not only did it burn 2 clean holes along the cutting edge, but it also welded the hinge. I was duly impressed... :)

This discussion seems to be way too complicated.

Two places I visit have NEMA 10-30 outlets. Why should I buy any of the adapters above and dial down the amps when 1) I can buy a NEMA 10-30 adapter from Tesla for $45 and then 2) an extension cord with 10-30 on each side?

Is that too simple of a solution?

If all you need is a 10-30, it is a perfect solution. The complex collection is if you feel you may need any of a number of adapters, and extensions. The ideal is to carry only one extension because to be rated for high current they tend to be quite heavy and bulky. After you have chosen one extension you choose the appropriate adapters, and then may have to dial down current.

@plusplusjames - it originated from the time before Tesla had many adapters... I used a 10-30 home made adapter for the first about 6 months until after much asking finally they had a couple at the factory and I got one.

Thanks for the get-backs. My 10-30 solution looks pretty good except for the $150 extension cord.

Ha - I had missed your post Brian H.

When I was a kid my brothers and I tried to make light bulbs. We stripped old copper wires and shaped a filament, and inserted the ends into an extension cord which we then plugged in. It did glow red momentarily... Then it went pow, right at the moment the circuit breaker flipped...

We had so much awesome fun in our attic.

I did successfully make a microphone.

@plusplusjames - If you only visit two places, then you don't need all of this. If you like to drive off the beaten path, where you may not find the type of outlet you need, or you may not be able to get close to the outlet you need, then the extension cord and "bag of adapters" can be a lifesaver. I can charge so long as I get within about 70' of a drier, welder, RV, or standard 110 (15 or 20 amp) outlet. That has come in handy several times.

Btw, I highly recommend getting the Tesla NEMA 5-20 adapter. I just finished a 24 hour trip (3 hour drive, stay overnight, drive back the next evening), and it was critical that I could get enough charge in that overnight period. The only plug available was a garage 120V plug, but luckily it was a NEMA 5-20, so with my adapter, I grabbed 50 miles of charge overnight versus 34 miles if I had only the default NEMA 5-15 adapter that came with the Tesla. Yes, that extra 16 miles did mean something - peace of mind and the ability to drive fast on the way back.

Various adapters do come in handy from time to time.

So far I haven't found the NEMA 5-30 mentioned. I have a house vacuum plugged into a high-amp 110V outlet. I know the adapter for the Tesla immediately drops the current pull if it senses 110V rather than 240V, but it would be nice to get ~24 amps from a 110V plug that already exists in my garage. It's plenty for my driving range. A NEMA 5-15 is not. I hate to invest in a 240V install when I don't really need it. Anyone know if the Tesla charger is current-restricted BECAUSE it's drawing from a 110V source or BECAUSE the 110V source won't supply more current? The designer for our house had installed nearly 100kW worth of solar panels, and put in industrial-grade wiring throughout, so there are a number of 110V high-current outlets that are NEMA 5-20 and 5-30. Tesla made it clear they won't provide a 5-30 adapter, but I think I could make one if the car can pull 24 amps from 110V. This seems like the correct forum to ask this.


(LMB spouse)

@Shop - Might want to be a bit careful with 5-20. Non-professionals who install outlets aren't always careful about wire size, breaker rating, or shared loads. If you know everything is good or you can check it, no problem. Otherwise...

@pstaffor - NEMA 5-30 are not very common, so I'm not surprised that Tesla won't be making such an adapter. You have several options.

1. Buy the Tesla 5-20 adapter. I believe (don't know for 100% sure though) that a 5-20 plug can fit into a 5-30 receptacle. With the Tesla 5-20 adapter, you'll be able to charge at 16A, 120V. This will give you about 5 miles an hour, or 60 miles for a 12 hour period.

2. Make your own NEMA 5-30 to NEMA 14-50 adapter, and then use Tesla's NEMA 14-50 adapter. You will then be able to charge at 20A (since Tesla's software limits you to 20A charging at 120V). This will give you about 75 miles of range per 12 hour period.

3. Splurge the $500 or so to have an electrician install a 240V receptacle.

As to why Tesla limits 120V charging to 20A, beats me. My wild ass guess is that they didn't realize there were many 30A 120V sources, and they decided to be ultra cautious and limit charging so as to not pop breakers in case people started making their own home made adapters and using them improperly.

Note that you should not use the same circuit as your house vacuum should you decide to use one of your 30A 120V circuits. The Tesla load and the vacuum load together would trip the breaker (hopefully).

@LMB - don't worry, the 5-20s I've seen were in relatively new condo garages - there is little doubt they didn't build them to code. The 5-20s weren't add ons...

@pstaffor - 100 kW solar array? Really? That's like 260 panels - That's like 10,000 square feet of panels - or about 1/4 of an acre.


If you have 100kW of solar, you should just get a old 90kW supercharger for your garage :)

@shop, your adapters PDF at is awesome. Thank you for sharing your knowledge!

I made a NEMA 6-50 to 14-50 adapter using the parts you specified. I'd love for the group here to take a quick look to make sure that nothing terrible will happen if I plug this in! Thank you. I am a new Tesla owner, and am super excited to drive it and to participate in this community.

Pictures here:

@public looks good.

Yes indeed, looks good.

@shop - you saved me. I had made my two 30A 240V adapters per your careful instructions and thought I was good to go for a KOA 30A charge at a friends permanent site. Then at the last possible moment I learned from your (updated) instructions that RV 30A hookups are completely different. Just had enought time to order and make my TT-30 adopter before I left yesterday for upstate NY. It's working like a champ and, without your detailed advice, would have been SOL. You're da man! Thank you.

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