Extension cord for charging from Dryer outlets

Extension cord for charging from Dryer outlets

Many owners say that if they are visiting a friend's home and need a charge, they rely on dryer outlet if available. In case dryers are away from garage or a place where car is parked, I am assuming that these folks are using an extension cord. What are the specificaitons and links for some of these extension cords? I am wondering if on road trip, we should also keep such an extension cord along with UMC for just in case. This allows us to get power from many homes at a faster rate than say 110 V.

plusplusjames | 01. Februar 2014

Great question! I've been looking at this and found this 10-30 extension cord:

I imagine for safety's sake that if you are connecting this outside you should wrap the join in Saran wrap to keep out moisture from rain, snow, dew, etc.

Has anyone else used this particular extension cord?

Tesla apparently does not sanction the use of electrical cords at this amperage (for obvious reasons).

RFD | 01. Februar 2014

There are two different 30-amp plugs that are commonly used for clothes dryers in the US, depending on local electrical codes and when the house was built. 10-30 is a three wire plug--L1, L2, and a combined ground and neutral. 14-30 is a four wire plug where the ground and neutral are separate. This is more common in newer homes.

Tesla sells adapters for both, but you need to be sure which one you need. For charging, you do not need the neutral, but you do need the ground.

Fifty-amp plugs have the same complication--6-50 and 14-50.

You can buy plugs, receptacles, and wire at Home Depot if you want to make your own.

amitb00 | 01. Februar 2014

I was looking at my dryer and indeed it is 14-30. Shape is like NEMa 14-50. So we may need two types of extension cords for two types of dryers. I am learning so much. If we use UMC to get power from 14-30 is it smart enough to not ask for 40 amps and trigger the breaker as I am guessing same cable will be going in 14-30 or 14-50.

Roamer@AZ USA | 01. Februar 2014

He common conductor pin is different on a 14-30 and a 14-50. When you use the adapter for the outlet the car will know what it is plugged into and set amps accordingly. You can also set amps manually in the car.

Roamer@AZ USA | 01. Februar 2014

Not sure that was clear. A 14-30 won't plug into a 14-50. And a 14-50 won't plug into a 14-30.

amitb00 | 01. Februar 2014

Thanks Roamer. Getting more clarity.

DouglasR | 01. Februar 2014

There are many threads on this topic. Perhaps the most comprehensive is this one:

If you look at my post on August 24, I list everything I got and where I got it. I based this set around a 50' NEMA 6-50 (welder) cord. I chose that cord for several reasons: with three wires, it is a lot lighter than a comparable four-wire cord, plus I can adapt it back to virtually any other outlet type, so I don't need to carry more than one extension cord. The cord is good quality, and they will even print your name on it. I have tried virtually all of the permutations and combinations in this set, and all have worked fine. In other words, I can charge from up to about 70' away from just about any drier, welder, RV, or standard 110V 15 or 20 amp outlet.

Always check the cord an hour or so after you plug in to make sure it is not getting warm.

jcaspar1 | 01. Februar 2014

I just did this with a 10g extension cord used to use for my table saw. Put a 14-50 female on one end, 10-30 (old style dryer) on the other and tried it at my In-Law's house. Turned the rate down to 24 amps. Worked great.
This is the best resource I have found (from link on TeslaTap site):

Pungoteague_Dave | 01. Februar 2014

I made my own dryer-to-1430 10-foot extension cable and outlet based on instructions on this forum, and parts from Amazon. Just make sure you use heavy enough cable. I have used it at several relatives' houses to extend the UMC's reach into laundry rooms and basements. I am not an electrician, but can connect A to B without causing a short. There's not much risk, as the car self-evaluates the connection and won't engage if you do something wrong. Your mileage may vary...

Dr. Bob Reinke | 03. Februar 2014

We bought a 100 ft 6 gage yellow contractor job site cord equiped with 14-50R and 14-50P on the ends at Menards. They also had 14-30 14-50 pig tail adapters. Actually got change from a couple of hundred dollars. For about half that cost they had plugs and drop-cord to make your own---but you woudn't get the nice molded plugs on the cord.

Dwdnjck@ca | 03. Februar 2014

I use an unused 10-30 dryer plug for all my charging. I did have it moved from laundry room to garage. It works fine at 17mph and stays nice and cool.

shop | 03. Februar 2014

You won't find a ready made dryer plug extension cord (either for a NEMA 14-30 or 10-30), so use one of the resources listed above to learn about and make your own.

aaronw2 | 03. Februar 2014

I made a 20 foot NEMA 14-30 extension cord using a nice outlet and plug I found at my local Ace Hardware along with flexible 10 gauge wire (rated for 30A). It cost me under $30 to make and worked quite well until I was able to install my HPWC.

riceuguy | 03. Februar 2014

For 14-50, just search Amazon for RV extension cords!

whitex | 03. Februar 2014

What I got is a 50Amp extension cord and 4 adapters for different plugs, including the 2 different dryer types:

30' 50Amp extension

Adapter 1:

Adapter 2:

Adapter 3:

Sorry, can't find a link for the last one, but you get the gist. The extension is also useful when I want to charge my MS outside my garage (my 14-50 plug is on the back of the garage as I back into the garage to get the most out of the space with 2 cars in it - both car driver sides facing each other).

shop | 04. Februar 2014

whitex - all three of those adapters you list WILL NOT WORK for Tesla charging. They all adapt a 120V source to the NEMA 14-50, but do it in a way that is useful for RVs, but useless for Tesla charging. Briefly, they take the single 120V hot from the 120V source and put it on BOTH 240V hots for the NEMA 14-50. The Tesla will see 0V when one of these is used.

Also you will rarely find a use for those three adapters. The first is a TT-30, generally found only in campgrounds, and usually there would be NEMA 14-50s available there. The other two are locking connectors generally only found on generators.

Finally, I like this extension cord better (it is far lighter, more supple, but it does cost more):

plusplusjames | 04. Februar 2014
amitb00 | 04. Februar 2014

@shop: Cable link from you costs $178 whereas whitex cable costs $104. So yours seems more expensive.
Third adopter by whitex (link below) seem to change from 14-30 to 14-50. Is that also from 120V and Tesla will see nothing. I thought third adopted can get us power from dryers from friend's place.

mantin | 04. Februar 2014

Based on above, just ordered dogbone adapter and 50 amp cord - camco. Hope it works as well as recommended. Thanks.

amitb00 | 04. Februar 2014

Hi Mantin, what do you mean by dogbone adapter? Can you provide me its link? Thanks

shop | 04. Februar 2014

@amitb00 - yes I said my extension cable costs more, but was nicer.

Third adapter from whitex does not change from NEMA 14-30 to NEMA 14-50. It adapts a NEMA L14-30 Locking Plug. Which is quite different. I find it very unlikely that a NEMA L14-30 can plug into a dryer receptacle.

shop | 04. Februar 2014

@plusplusjames - I stand corrected. That is indeed a NEMA 10-30 extension cord for an old style dryer receptacle which would work fine for Tesla charging using a Tesla 10-30 adapter. Kinda expensive though.

Solarguy01 | 04. Februar 2014

James the cord you show is 10 gauge wire while the is 6 gauge wire for caring 50 amps with a 8 gauge ground wire. This cable has a lot more copper in it to carry the higher amperage. I dud choose this type of cord as it can safely carry the amperage required for a faster charge. You get what you pay for.

whitex | 04. Februar 2014


You are correct, I won't find much use for the the first two adapters unless I find a 220V generator with one of those plugs. So far I've only used the extension cord. The 4th adapter I got (haven't used it yet) is a 4 prong dryer plug to NEMA 14-50 - it has a 1:1 connection for each phase, neutral and ground, so it should work fine.

I think the key here is to get one extension cord and a set of adapters for the the extension cord plug, rather than many adapters for the Tesla charging cable (which would require folks to get many different extension cords). The only drawback is that you have to limit your charge current manually according to what you plug into, rather than it being automatically detected by the car (I am assuming here, haven't used any of the other Tesla adapters).

whitex | 04. Februar 2014


Correction, after looking at the first 2 adapters again, I think you are right, they won't work.

Rheumboy | 04. Februar 2014

plusplusjames | 05. Februar 2014

@solarguy01: Colin from Tesla called me yesterday and explained to me (as someone who knows nothing about electricity) the importance of gauge. This confirms what you wrote. The lower the gauge, the safer the wire. I think reducing the possibility of fires at my friend's and family's houses is kinda important.

Accordingly, I am now thinking of buying the cable you suggested together with adapters from

My Model S doesn't get delivered until March 28th so I have lots of time.

plusplusjames | 05. Februar 2014


slipdrive | 05. Februar 2014

Several other considerations when approaching these projects:
1. Know where the outlet breaker is, so it can be flipped if things go unexpected. Advisable not to unplug at these power flows, which is often the first instinct.
2. The longer the extension cord, the bigger (lower number) gauge wire required. There are many charts and graphs.
3. Might consider picking up a Class C fire extinguisher at Home Depot.

BrassGuy | 05. Februar 2014

I bought a dryer cord and a 14-50 outlet to charge while away in ME, since Tesla doesn't sell a 10-50 adapter. Cost about $35, and easy to put the 2 together. Luckily I didn't need to add much length to use their outlet.
I have a 10-50 in my house too for a dryer, but it's wired to a 30A breaker(!) so I suggest anybody finding this old outlet check the breaker panel before using it.

shop | 05. Februar 2014

plusplusjames - there are several product links and conversations on this thread so it is hard to keep track of it all. Yes, the link that you posted at steambrite is only a 10 gauge wire, but it has connectors only for 30A plugs. 10 gauge wire is rated for 30A loads, so there is nothing wrong with the steambrite extension cord if all you need to do is to extend a NEMA 10-30 dryer connection.

The 50A extension cords do indeed have 6 gauge wire, but that's because they are rated for 50A.

And yes, if you are looking for a GENERAL solution for multiple plug types, then get a 50A extension cord with NEMA 14-50 ends, and buy adapters from or make your own following this document:

WARNING: the current software release that most people have in their cars (5.8.4) has a dangerous bug in that if you are charging and you dial down the amps to a safe setting for a home made adapter (eg. you plug into NEMA 10-30 via a Tesla 14-50 adapter and a home made adapter), the software has a bug that if it detects some anomalous current drop or spike, it will override the user set amp draw to 80% of the Tesla adapter's rating (ie. it will reset it to 30A for a 14-50). This reset will exceed the maximum safe continuous current draw rating for a 10-30 (which is 24A). I told Tesla about this bug over a month ago, haven't received a reply yet, however reports in the field are that there is a 5.8.6 software release being pushed out that fixes this bug. So if you use a home made adapter I recommend calling Tesla ownership and requesting 5.8.6 for this reason.

Panoz | 05. Februar 2014

I have little to add here other than this thread convinces me to NOT make my own adapter/cord. I'm sure many of you have had good experiences, but as the son of a lawyer let me just state that you are asking for trouble. If you were to use a jury-rigged extension cord and a fire began, you would have full liability as far as insurance goes. If Tesla says "no extension cords", even if it's overly cautious, you're asking for trouble. Burn your own house down, but don't burn down someone else's. It wouldn't take an insurance attorney 5 seconds to look up the "no DIY" recommendation on the Tesla website and unload both barrels at you.

I don't want to sound harsh, but having to carry around a fire extinguisher in case your homemade extension cord goes south would be bad...

plusplusjames | 05. Februar 2014

Jeepers! I picked the wrong morning to stop drinking!

sbeggs | 05. Februar 2014 are clearly in "Airplane" mode!

plusplusjames | 05. Februar 2014

That being said, and notwithstanding software bugs, inadequate gauge, defective cables, unknown circuit breaker locations, underpowered fire extinguishers, incendiary forum posts, hell, high water, and the Second Coming -- I will need to charge this damn thing when it arrives in late March.

Hopefully my charred remains will not be meeting anyone else's in the afterlife this coming April.

slipdrive | 05. Februar 2014

@shop Thanks for the information on the software bug. Hopefully, folks have the house wiring and breakers to protect the house wires. It is the extension cords/adapters and all those screwed connections that are potentially vulnerable. @plusplus We are still all better off than driving around sitting on top of a gasoline tank! You will be love this car ....

Big T | 05. Februar 2014

This issue of insurance not covering you has come up before, particularly in threads related to self-installing a 14-50 receptacle. While having dinner with an insurance attorney, I asked him about this issue. This man is a partner in one of the largest U.S. firms and is an acknowledged expert in insurance. He is licensed in multiple states and even argues cases before federal appellate courts. What's more, he is hired by insurance companies to defend the insured or to deny a claim by an insured. He says that your homeowners insurance is there to protect you even against your own negligence or stupidity. You have to have been found to be willfully or grossly negligent for a claim to be denied.

Not tightening a screw enough or forgetting to dial down the amps is not gross negligence. If they could prove you knew better and purposefully drew higher amps because you wanted to charge faster then they would have a case against you for gross/willful negligence. If your insurance company were to deny your simple negligence claim (by calling it gross negligence), the company can be defeated by a decent attorney.

Of course, you may just want to protect yourself from even the possibility of a denial and the hassle of fighting it.

plusplusjames | 05. Februar 2014

Hey, I just learned that there are 2 -- dos, deux, due, zwei -- different connectors for a NEMA 10-30. An old one and a new one.


Does anybody know if the NEMA 10 Universal adapter handles both? The illustration shows a 10-30 and a 10-50.

Tâm | 05. Februar 2014


When you use your friends' & family's dryer socket, you've got to know whether it's an old standard or new.

Old: 3 Prongs, NEMA 10-30
New: 4 Prongs, NEMA 14-30

They are all 30 amperes but different numbers of holes to fit in.

shop | 05. Februar 2014

@plusplusjames - not quite right - there is a single connector for a NEMA 10-30 and a different connector for a NEMA 10-50. That EVSEadapter does actually fit both the NEMA 10-30 and the 10-50. It's a nice adapter to have for just this reason.

What Tam is referring to is that there are two different dryer sockets commonly in use. A NEMA 10-30 and a NEMA 14-30.

What were you thinking of charging with, james?

@Big T - thanks for the info about insurance. I always thought the overreaction on these forums about anything DIY was a bit much.

plusplusjames | 05. Februar 2014

@shop: here's what Colin wrote me:

Here is a photo of the NEMA 10-30 and its orientation;

There are old NEMA 10-30 outlet that look like this;

Obviously these are slightly different so the one at the other house may need to be swapped out for the newer 10-30 to be compatible with our adapter.

I asked: Are there really 2 different 10-30 outlets? Looks like you have sent me a picture of a 14-30 and a 10-30. Please clarify.

Colin: Yes there are two different 10-30 outlet, the first picture is of the newer one that is the same configuration as our adapter. The second picture is of the old one which I don’t think they sell in the stores anymore and is not compatible with our 10-30 adapter.

So, I am not sure how to reconcile your comments with Colin's.

GeekEV | 05. Februar 2014

Try StayOnline, you can get all kinda for extension cords, etc. there.

plusplusjames | 05. Februar 2014

I have corrected Colin from Tesla! He was confusing the TT-30 with the 10-30. There is only one 10-30. So we are all good.

My plan is to install a 10-30 where I rent here in Glenside, PA (Philly suburbs). The whole house only has a total amps of 200 so I can't go with a 14-50, it's just too much. The 10-30 should give 17 mph which will give me 130 miles overnight. My round trip commute is 60 miles so that will keep me in an accumulating balance.

Tâm | 05. Februar 2014


Good that you did. I wonder whether Tesla staff should pass basic electric theory and physics first before they are allowed to work with customers :)

shop | 05. Februar 2014

Good God. While I love Tesla and everything they do, the lack of basic knowledge of some of their people continues to amaze me. It would never have made sense for an electric socket standard to have two shapes. Sheesh.

If you are installing a new socket, I would recommend installing a NEMA 14-30 since that is the new standard. The 10-30 does have one less wire, so it would be slightly cheaper, but it is an old standard that does have some deficiencies (like no safety ground). But either will work.

Were you actually going to install a new outlet, or use an existing 10-30 at the rental house?

plusplusjames | 05. Februar 2014

@shop: Install a new outlet outside.

You see, at my other hub (ski house near Hunter, NY), I have an old dryer plug to use. So I was thinking of installing a new (old) 10-30 so I can use the same prongs at both places.

shop | 05. Februar 2014

@plusplusjames - ah, I see. Sure, whatever, I think this thread has beaten this horse to death already :-)

Brian H | 06. Februar 2014

Those pix that didn't show up can be posted only if web-hosted. In general, display full size, rt-click image for context menu, select Copy Image Location, paste in this HTML:

<img src="URL" width="600">

dave_wu | 03. März 2014

I'm taking delivery of my model s soon :-). I'm having a electrician install a 14-50 NEMA. in reading this thread looks like I can use a extension cord . I'm so confused. I'm not technically savy. Which cord should I buy and will be safe? Sorry I sound stupid as you guys might of answered in this thread.


amitb00 | 03. März 2014

What is your purpose to get the cord?