120V to 240V outlet without any electrical work?

120V to 240V outlet without any electrical work?

I am getting ready to put a deposit on either a Model 3 RWD or an case it makes a difference (I'm struggling to choose....if anyone wants to chime and help sell me on one or the other, I'd appreciate that too).

Main question: I rent a house and cannot install anything permanently at this residence. So, I am wondering if I can buy something that would make a 120V outlet into a 240V outlet. Is that possible?

RES IPSA | 12. Oktober 2018

Many other owners will know more than me on this subject, but you do have some options for charging:

1. Use a supercharger or a Level 2 charger in your area (a lot of those are free) can help

2. Unplug your dryer if it is in your garage once a week to charge your car (I think that is a Nema 14-30 outlet) You would need to buy an adapter from the Tesla website. Probably less practical would be to use your oven plug which is normally a Nema 14-50 outlet.

3. Talk with your landlord about you paying to improving his property by adding a new 240v outlet in the garage.

As for AWD or RWD, it depends on where you live. If you live where it snows or freezes for 2-3 months out of the year, buy AWD

Jlomb436 | 12. Oktober 2018

Honestly, depending on how much you drive, I'm currently getting awya with 120. It only charges about 50 miles overnight (12 hours), but i sometimes drive 5 miles to work and sometimes 100 when I have to meet clients. All in all, it's working now. So it's possible.

neiljbailey | 12. Oktober 2018

Firstly I would say that charging at 120v is possible - if you are not doing that many miles/km per day it is quite possible to re-charge at 120v overnight. Especially if you might have access to charging during the day - my local grocery shop offers free fast charging while parked there (although the parking itself is not free...)
I am not an electrician but I can tell you you cannot "convert" a 120v outlet to 240v.
As the answer above from RES IPSA implies, most houses do have a 240v circuit for dryers and (sometimes) stoves. It is relatively cheap to add an outlet to this circuit provided the capacity is there - your landlord may not object if you explain it as he or she will then benefit from that in the future - but you will need an electrician to do it safely.

I have an AWD because I need to drive in snowy conditions 4-5 months per year.

FromSeatosea | 12. Oktober 2018

Couple notes:

My commute is 60 miles round trip 4-5 times a week (sometimes I work from home). I also typically drive an additional 100-120 miles on the weekend (LA!) being able to get my 60 miles back every night would work. I can plug it in at 6pm and I leave the house around it would have 12-13 hours to charge.

I can charge at work for free on a rotating basis. I work in Santa Monica on thinking there are places there I can charge for cheap/free near work as well.

I also found this thing:

Wouldn't this work?

Coastal Cruiser. | 12. Oktober 2018

It is *possible* to turn a 120V outlet into a 240V, but a number of variables must line up for you.

1) You would have to do some rewiring at the panel. This would have to be undone of course when you move.

2) You would have to change out the outlet (likely a NEMA 5-15) to a NEMA 6-15. If you are lucky enough to have a 20A outlet in the garage (NEMA 5-20) then you could swap in a NEMA 6-20. Again, would have to be undone.

3) Those two procedures may sound like a pain, but the nice thing is the wiring does not have to be upgraded.

4) If the circuit breaker that feeds the outlet you want to upgrade feeds other outlets, lights, etc. in the garage then this strategy won't work.

5) You also have to have an open slot in the panel to upgrade from a single-gang 120V breaker to a double-gang 220V split-phase breaker.

If any of this scares you or does not sound familiar then you should have an electrician check out your circuits to see if upgrading an outlet to 220V is feasible.

Finally, do you NEED the higher charging rate. You might want to check the Model 3 Home Charging guide, which has a calculator for how much charging capacity you need based upon your driving patterns:


FromSeatosea | 12. Oktober 2018

Just a follow up comment...thanks for the replies...

I shouldn't have said "convert" I meant more of "can I connect two different 120V outlets to some adapter like the above and make it into 240V power?

Coastal Cruiser. | 12. Oktober 2018

Short answer, NO.

It's funny, because if you HAD to do something like that, and you knew which legs of the incoming street line went to what outlet via the breaker box, you could HACK something together. But that is sort of getting into MacGyver or The A-Team territory.

FromSeatosea | 12. Oktober 2018

Damn it. -_-

elecfan2 | 12. Oktober 2018

There is a box that can do this but you have to plug them into different phases, a hassle. Look into a very heavy 220v extension cord and use the dryer plug, also look at dryer buddy.

FlyingPig | 12. Oktober 2018

Is it possible? Yes. Is it safe to use even if you do that? Absolutely not.
120v will likely give you about 4 mph. So, if your commute is more than 20 miles each way, you will just have to catch up on the charging during the weekend, or stop by a supercharging station once a week (you'd probably get more if you work regular hours and not 15 hours a day)

FromSeatosea | 12. Oktober 2018

The dryer buddy recommendation above is legit, thanks!

jjgunn | 12. Oktober 2018

Here's the box ewd7 is referring to. Before you go buy this, make sure you have (2) separate 20 Amp circuits that are out of phase. You can test your outlets with a tester first. Incidentally, one comes with the package too.

Output is NEMA 6-20 & I get 4kW to my Tesla. On the model 3 you should get about 15 MPH. Provided all the pre-reqs are in place for you. Good luck.

Coastal Cruiser. | 12. Oktober 2018

That little box is cool. One caution though. That included tester is likely not going to identify which leg of the split phase you plug it in to. There's likely a procedure that comes with the device though. And it seems like you'd have to get lucky that the garage has outlets derived from each of the two phases. But it sounds like you've done this so you can't argue with success. I'm curious how you identified which outlets ran off which phase jjgunn.

FromSeatosea, if you go the dryer buddy route I strongly suggest you first read the dryer buddy section in the link I gave you earlier. The passage is a write up from one of our regular forum contributors about the right dryer buddy to purchase.


jjgunn | 13. Oktober 2018

I live in an apartment too. Found the (2) circuits wired in the kitchen. (1) for the food garbage disposal & the other is an outlet where my microwave is plugged in. Both outlets are 120v @20 Amps

Guess I just got lucky both were out of phase & non-GFI.

I've charged the MX 100D numerous times now. Car reads 233v-234v at 16 Amps. Never blow a breaker as long as I don't try to use the microwave or the toaster or hot water kettle. Haha

Always charge after 9 PM & stop before 7 AM.
Used enough kWh's to get into Tier 2 & bill was still only $60 this past month.
It works for me but people need to be cautioned I'm in a unique situation so it may not work for them.

1 more thing I'll add is be 100% certain you're using proper extension cables (12 awg) rated for 250v-300v & 20 Amps. Don't cheap out & use grandma's cell phone extension cable that reaches her nightstand. Buy properly rated cables for your entire setup.

Mzab | 13. Oktober 2018

And you wonder why there are house fires. I’m hearing some scary stuff. Fromseatosea: Do it right or don’t do it at all. Stick with the 120 or talk to your landlord about adding a 240 outlet in the garage. It cost me $1400 for an electrician to run 240 line to the garage. If you can’t flip the bill for that, you probably shouldn’t be buying a $50k plus car.

jon | 13. Oktober 2018

@FromSeatosea no there is nothing you can buy that is going to be plug & play kind of setup. At a minimum you would have to change wiring in the breaker box.

1) How far do you drive per day and is your car parked for 8+ hours a night? 120v may be enough for you with a trip to a supercharger every couple of weeks to help fill it up if you can't quite recharge your use daily but are close.
2) Is there room in the breaker box? I asked the people who own the house I am renting if they were ok with me installing it at my expense and they were. I found an electrician that did the install directly below the panel which is in the garage for only $325 and now I have a 6-20 outlet (I installed it for my Volt before the M3 came). I did this at 2 previous rental homes as well.

kevin_rf | 13. Oktober 2018

Just a side note, while waiting to service for my wall connector to be turned on I used a very heavy duty RV extension cable on the houses 120v and was seeing 5 miles of charge per hour.

If you can plug the wall connector directly into a 120v outlet or have a heavy duty extension cable (often referred to as an RV) 5 miles per hour charging is quite doable. Also, I second the drier buddy idea if your drier is in a convenient location to run a cord to. It just plugs in between your drier and the outlet.