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50 AMP Extension Cord--important to Have??

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There are many threads regarding extension cords. I don't think you will find much use for this very heavy/bulky extension cord that carries an extraneous neutral conductor that actually has no connectivity to our Ses. The dogbone listed will most likely not function with the S as I believe the neutral and L1 are crossed for S charging. Sorry for sounding so negative, but just don't want you to waste money unless you have a need. Others may chime in, with legitimate counterpoints. Just my $.02.
 
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If I lived in California right now I wouldn't worry about an extension cord. My charging options in much more rural areas in Arkansas and MO make an extension an important option--I've had to charge through the window of my parents' house while parked in the front yard running the cord into the laundry room to the dryer outlet! That said, I don't carry it unless I know I'm going to need it or that there's a chance I'll need it on a very rural unfamiliar route.
 
NorCalSJ said:
DO NOT BUY THIS ADAPTER! It will not work with a Model S.

A couple of people hinted at the issue. The problem is that it is wired thusly:

1 - TT-30 ground <-> 14-50 ground
2 - TT-30 neutral <-> 14-50 neutral
3 - TT-30 hot <-> 14-50 hot #1
4 - TT-30 hot <-> 14-50 hot #2

Connections #1 is fine. Since the UMC never looks at neutral, connection #2 is irrelevant. Connections #3 and #4 are your charging downfall. The Model S draws charging power from the two hot legs. Since, with this adapter, both pins of the 14-50 are connected to the same hot leg, the voltage difference across them is 0V (not 120V, as you would hope).

This adapter (mostly) works for RV's, as it powers up both 120V legs in the RV. 240V appliances in the RV don't work, however, for the same reason the Tesla won't charge - they see 0V hot-to-hot.

Cosmacelf's home made charging adapters will show you how to wire a TT-30 adapter for a Tesla: http://cosmacelf.net/Home Made Adapters.pdf
 
Don't waste your money... I bought one and used it daily until I realized if I just backed in my UMC would reach. After that, the only time it's been used was when I loaned it to FLDarren for his road trip to visit family in KY. I think he used it once or twice. Had he not had it I'm sure he would have figured something else out.
 
As others have said, you most likely will not need a 50A-capable extension cord. Think about where and when you would even use it... You would never use it at home (just place a 14-50 or HPWC in reach of the car). You won't need it on any supercharger enabled routes. That leaves non-Supercharger enabled routes and destination charging -- so then you need to look at where you would charge. If you charge in an RV Park, you will park right next to the 14-50, so no extension needed. Perhaps you'd need it to plug into someone's drier outlet if staying with friends or family -- but would you even need to do that?

In my case, I purchased an extension cord for our AZ to BC road trip last summer -- but just bought a 20A version compatible with either the stock 5-15 adapter and the optional 5-20 adapter. Yes -- those are only 120V charging, but that was all that I needed to close the charging gaps on our trip. I ended up using it twice -- once at a hotel to add ~30 "insurance" miles overnight since our next leg required a ~90% Charge and it was going to be raining the entire drive. The other was to charge while at my in-laws for a week - there is one public charger on the island they live on, so we charged on that when in town and used 120V at their house. The rest of the charging on that trip was Superchargers, the Disneyland parking garage J1772s, and a hotel off the Supercharger route that had a J1772...
 
Also, these TT-30P/14-50R adapters are wired correctly for charging (but not for an RV):

NEMA 14-50R to TT-30P RV Plug Adapter
NEMA 14-50R to TT-30P RV Plug Adapter Cord

If you are handy with wiring, another option to consider is build your own. If you are willing to limit to 30A outlets, you can use 10/3 SOOJ cord, which is way lighter than the 6/3+8/1 in the Camco cord. This thread is worth perusing:

14-50 adapters vs multiple extension cords

I think there's something to be said for:
  • A custom 10/3 extension with an L6-30P on one end and a 14-30R or 10-30R on the other.
  • Use the 10-30 or 14-30 UMC adapter to limit charge power to 24A max (the 14-30 seems to be missing from the accessories store?!?)
  • Custom adapters for whatever plug to L6-30R. Adapters twist-lock securely onto the cord for positive engagement and can't come undone.
  • Make a 14-30P to L6-30R adapter, without the neutral pin on the 14-30 (which wouldn't be connected anyway). Then you can plug safely into any 14-xx outlet you find. You won't pull max current from a 14-50 or 14-60, but at least you can use it.
This is lighter and more versatile than multiple cords. You do loose the ability to pull max current from a distant 14-50, but so what. Besides, I suspect (a) driers are closer to garages than ranges, and (b) every dryer plug I've seen is reachable without moving the drier (the venting holds it away from the wall). I've never seen a range plug that is accessible without pulling out the stove.
 
Unless there is a known place where you are going to need the extension cord, such as a relative's house that you visit, you'll never use it--and a 30 amp dryer extension cord and the Tesla adapter would likely be more useful there. I purchased one when I got my Model S and gave it away to the local EV club. Basically, if you use RV parks, you'll always be within a couple of feet of the plug. If you use Superchargers, you'll never need one. Public chargers are J1772. PlugShare Tesla owners mainly have HPWCs.
 
There are two times in the past year I've used my 50 amp extension cord. First I was at a rented condo, only 120v plugs nearby the car. While I could have charged with that, it wouldn't have worked had I only stayed one night. Anyways, I ended up doing a direct breaker connection (yeah, I. carry a couple of 50A breakers with me, I'm a bit extreme), and I need a 50A extension cord to reach the interior breaker panel. The other time was in the mountains and there were trees blocking how close I could park to our cabin, and the cabin had a NEMA 10-50 plug for a stove that I used, so again the 50A extension was essential.

So, as usual, it all depends on your own specific use cases...
 
I've used mine. But I drive a lot - 30,000 in one year of ownership. I'm in the mid Atlantic and we don't have the density of superchargers. I have a 50 amp and 30 amp cable I carry all the time and I have used it at shore power docks, dryer outlets and campgrounds. I have also used it to get around ICED charging locations.
 
DO NOT BUY THIS ADAPTER! It will not work with a Model S.

A couple of people hinted at the issue. The problem is that it is wired thusly:

1 - TT-30 ground <-> 14-50 ground
2 - TT-30 neutral <-> 14-50 neutral
3 - TT-30 hot <-> 14-50 hot #1
4 - TT-30 hot <-> 14-50 hot #2

Connections #1 is fine. Since the UMC never looks at neutral, connection #2 is irrelevant. Connections #3 and #4 are your charging downfall. The Model S draws charging power from the two hot legs. Since, with this adapter, both pins of the 14-50 are connected to the same hot leg, the voltage difference across them is 0V (not 120V, as you would hope).

This adapter (mostly) works for RV's, as it powers up both 120V legs in the RV. 240V appliances in the RV don't work, however, for the same reason the Tesla won't charge - they see 0V hot-to-hot.

Cosmacelf's home made charging adapters will show you how to wire a TT-30 adapter for a Tesla: http://cosmacelf.net/Home Made Adapters.pdf


uh I own this exact adapter and have used it just fine on a few occasions...you just need to be careful to drop the amps down before plugging it in.

to answer the OPs question, yes on several occasions I've needed it on some trips to charge at friend's houses off their dryer outlets. so I think it's worth it.
 
I made a 50A extension cord using SOOW 6/3 and a Camco 14-50P + 14-50R, with the neutral disconnected (Labeled "NOT FOR RV USE - TESLA/EV CHARGING ONLY")

I use it *constantly*. First of all, at my house, I am trying to sell the house, and it wasn't really worth the effort to put a 14-50 plug where I actually would need it to be for charging, but rather just put it directly next to the breaker panel. That is perhaps a very unique situation, but I also use it for destination charging when visiting family. The best option there is using the drier plug (10-30 -> 14-50 adapter) + 14-50 extension cord. Sure, I could back in to their garage -- but that would be very difficult given the way their driveway/garage is set up, and also would demand that I displace their normal parking -- with the extension cord, I could easily pull in forward to their garage, or alternatively, just park outside.

In fact, there have been very few times I have used the UMC without an extension cord.

Recently, there was the "Street Car Drags" event at Palm Beach International Raceway (many videos from this are floating around). The venue promised 10 charging stations, but only 2 of them worked. I needed a charge to make it home, and after another Tesla was finished charging (and the owner nowhere around), I was able to use the extension cord to be able to charge. Flexibility is priceless.

If you walk around the service area at Dania Beach, they are using a premade Camco 14-50 extension cord. Clearly it's not just a few crazy people who can find a good use for it.
 
I made a 50A extension cord using SOOW 6/3 and a Camco 14-50P + 14-50R, with the neutral disconnected (Labeled "NOT FOR RV USE - TESLA/EV CHARGING ONLY")

I use it *constantly*. First of all, at my house, I am trying to sell the house, and it wasn't really worth the effort to put a 14-50 plug where I actually would need it to be for charging, but rather just put it directly next to the breaker panel. That is perhaps a very unique situation, but I also use it for destination charging when visiting family. The best option there is using the drier plug (10-30 -> 14-50 adapter) + 14-50 extension cord. Sure, I could back in to their garage -- but that would be very difficult given the way their driveway/garage is set up, and also would demand that I displace their normal parking -- with the extension cord, I could easily pull in forward to their garage, or alternatively, just park outside.

In fact, there have been very few times I have used the UMC without an extension cord.

Recently, there was the "Street Car Drags" event at Palm Beach International Raceway (many videos from this are floating around). The venue promised 10 charging stations, but only 2 of them worked. I needed a charge to make it home, and after another Tesla was finished charging (and the owner nowhere around), I was able to use the extension cord to be able to charge. Flexibility is priceless.

If you walk around the service area at Dania Beach, they are using a premade Camco 14-50 extension cord. Clearly it's not just a few crazy people who can find a good use for it.

+1

I made a 60ft 14-50 extension cord. I have only used it twice but both times I used it, it was priceless to have it. I would buy one just to be on the safe side.
 
uh I own this exact adapter and have used it just fine on a few occasions...you just need to be careful to drop the amps down before plugging it in.

yo

Might you actually own a similar looking TT-30P to 14-50R (but wired specifically for Tesla charging, maybe a Conntek?) supplied by a 3rd party EV adapter manufacture? Cause I REELY fail to see how the OP's Camco 55185 adapter could possibly function properly as stated by tga. Unsure as to why you would need to dial it down as I thought our early cars only max "pulled" 20A @120v from said properly wired adapter (Cos, Cott ?).
 
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I made a 30' extension cord from some 10/3 soow. I have a 14-50 female on one end and a 10-30 male on the other end. Works great for charging from old style dryer outlets. Can only charge at 24 amps (17 miles per hour) but it is cheap, light weight and great for overnight charging at the in laws. Can easily change the male end to a 14-30 for newer dryer outlets if needed.
 
yo

Might you actually own a similar looking TT-30P to 14-50R (but wired specifically for Tesla charging, maybe a Conntek?) supplied by a 3rd party EV adapter manufacture? Cause I REELY fail to see how the OP's Camco 55185 adapter could possibly function properly as stated by tga. Unsure as to why you would need to dial it down as I thought our early cars only max "pulled" 20A @120v from said properly wired adapter (Cos, Cott ?).

It know it's the exact same one because when I click the amaZon link my account shows "you purchased this item on xxxx date", lol so yes it's the exact one linked.
 
It's hard to imagine where someone would actually use a NEMA 14-50 extension cord. I've charged at campgrounds, and the UMC works fine. A better thing to have in the car at all times is a spare UMC. I do carry a 10 ga. 25-foot 120V extension cord, which I have used on one occasion.

Easy. Visiting friends whose dryer outlets are further than 25ft from the garage.