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Extension cord for supercharger help

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No, hardly any of them are set up in that way, and the ones that are - aren't going to run that fast anyway because my car is older and limited to 120kw charging. Well within their capability for the dual 2-gauge wires (which is what Tesla uses for the 250kw chargers that aren't liquid cooled!) without any special magic.
Just saying you are wrong here, all Tesla Superchargers, V3/V4, that can output 250kW use liquid cooled cables. You are claiming that you are using one of the 250kW rated cables, so you should see the liquid cooling apparatus in it. (If it isn't maybe you have a V2 150kW cable?)

I wish that I had something to report. I have been completely unsuccessful at making the cable get recognized at a charger.
I would guess that a likely culprit is doubling up the electronics in the handle. (Like the transmitter in the handle, that by the way is not Bluetooth, I'm pretty sure it is a 433 MHz signal.)

Have you tried using it as an extension for AC charging? If so, does it work for that?
 
The people who told me that it was a 250kw capable cable were the guys who install and service the pedestals, so talk to them. I bought it off Ebay, it has dual parallel 2 gauge (four large conductors) and no liquid apparatus at all. It is the same as the heavier thicker SC cables that are around 1.5 inches outside diameter.
 
it has dual parallel 2 gauge (four large conductors) and no liquid apparatus at all. It is the same as the heavier thicker SC cables that are around 1.5 inches outside diameter.

So then it’s definitely a “v2” cable. V2 superchargers are 150kw max. I suppose whether or not the conductors can handle more is an open question, but a cable like that never sees more than 150kw in the field.
 
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So then it’s definitely a “v2” cable. V2 superchargers are 150kw max. I suppose whether or not the conductors can handle more is an open question, but a cable like that never sees more than 150kw in the field.
That would be fine - I have a 2016 X that has only sporadically (and under near-perfect conditions) reached 175kw charging speeds on its original 400v battery. Even then, it only is at that peak for a few seconds at most, and then is tapering down steadily. A cable that is designed for 150kw would be OK by me, it wouldn't be at higher levels long enough to raise the temperature to unsafe levels- and the pedestal would STILL be monitoring its own connector temps, which would provide safety for the whole link.

I just want the thing to be recognized by the pedestal, which is where I'm stuck at the moment.
 
i believe ur problem is here...

1705778221483.png


u have 2 sets of R1/R2 which creates wrong resistance...
 
That's what I believe as well, but I haven't had a chance to mess around with it. The issue may be that I can't get to the proximity wire in the handle end where the resistors are, to make it a true straight-through and bypass those resistors. That COULD be the solution. Does anyone know a way to disassemble the NACS handle from the end of the cable without breaking it?

Or from another way, I know there are NACS female (car side) to J1772 adapters out there for people to use the UMC with their non-Tesla car. Does anyone know if they are straight-through and not with a resistor under the button? I could (in theory) use the NACS female (car side) adapter and a J1772-to-NACS (what we normally have for J1772 pedestals) to make both ends of the connection with a J1772 cable in the middle. MAYBE.

Still messing with this. I've also heard that perhaps there's a magnet involved in the connection?
 
The issue may be that I can't get to the proximity wire in the handle end where the resistors are, to make it a true straight-through and bypass those resistors. That COULD be the solution. Does anyone know a way to disassemble the NACS handle from the end of the cable without breaking it?

I bought this J1772-to-NACS adapter to build a custom L2 adapter (long story). Disassembly was easy by first removing the flange portion from the J1772 side using an oscillating multitool, then once mostly flush with the J1772 inner insulator stand off (that houses the recessed J1772 side pins), I used a basic 4-1/2" disc grinder to take it down fully flush around the whole adapter. Once done, the two halves are held together only by the short layer of "glue" between the two halves, so a quick pry with a flathead screwdriver separates them lickety-split. Inside, the heavy NACS connectors appear as one solid straight through piece to the J1772 pins. It looks like it's offset CNCed (with perhaps stamping the final pin shape) and plated with electroless nickel.

I used bare 24awg solid wire to wirewrap my stripped 12awg stranded wire to the pins, then used my grandfather's circa-1940s 100W soldering iron to flow the connection with a bit of 60/40 just to give it a positive physical connection that couldn't vibrate loose. I wish I had cut the long J1772 pins shorter to make for a smaller/lighter adapter, but I was too lazy to redo it after soldering, so I don't know what the material is made of. It might be copper, but my guess is beryllium copper, which is why was hesitant to cut them, as I didn't have a mask in immediate reach and beryllium is highly toxic to us breathing meatbags.

Even if not an esoteric copper alloy, if it's beryllium copper, they would likely handle the amperage without issue for the relatively short SC session. For the SC adapter, leaving the pins uncut and tightly wirewrapping the J1772 side with high-strand cable I think would work quite well. You might be able to find some ferrule tubes to compression crimp the wire around the pins as well. Grabbing one of the adapters for 10 bux and giving it a shot isn't much of an investment if it doesn't work.



All that said, based on the schematic, you can likely just "open" R1 and R2 resistors in the NACS handle by strategically putting them into overcurrent condition by connecting the PP and GND lines to a high-current/high voltage power source while ensuring that S1 is in the "open" position. It would be best to do this from both the NACS connector side and the pedestal side of the cable, to lessen the chance of the PP line going open. If successful, the R1/R2 path would go open once one of them overheats enough. This would of course also cause S1 to be non-functional, but I think that's the point, right ? If you can determine the values for R1/R2, you can try to mock up the circuit yourself to see how easy it is to burn up the resistors vs the cable.

I'm excited to hear how you make out on your next steps !
 
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Here’s those pics I promised of the disassembled adapter I mentioned above.

Btw- did you find out how many ohms those resistors on the PP line are ? You should be able to determine the value of each of them by comparing first the resistance between PP and GND, engaging S1, then measuring again. Assuming S1 is a NO momentary as in the schematic:

R1 = Rpp-gnd
R2 = R1 (-) Rs1-pressed

Knowing those values, I can likely give you some recommendations on the supply required to over-current one or both (and if it even makes sense).

IMG_0469.jpeg


IMG_0471.jpeg



IMG_0473.jpeg
 
I have not had the opportunity yet to test the cable, it is in Florida and I'm in CT at the moment - but I will hopefully be loading up the cable and more of my tools soon to continue my move. Definitely would like to get this resolved soon, towing a trailer with the Tesla is painful at chargers.
 
It appears that Tesla is going to be offering a Supercharging extension cable: https://www.tesla.com/support/supercharging-other-evs#cable

Does the Supercharger cable reach all EVs?
Most Supercharger cables at NACS Supercharger sites should be able to reach your EV charge port, however, in some cases you might have to park over the line in order to charge comfortably. Avoid parking diagonally to reach the cable and try to obstruct as few charge posts as possible. Charge port locations vary by EV model, which requires cable sharing between adjacent stalls at many sites. Tesla is rapidly deploying our latest V4 Supercharger post which reaches all EVs in the same Supercharger stall. Additionally, we encourage all vehicle manufacturers to standardize charge port locations to the rear driver side or front passenger side.


We are working on an NACS to NACS extension cable, which will be available for purchase in the future.
 
@geordi Feel free to DM me if you’d like help “fixing” the marker resistors in your extension cable. It really should be pretty easy.

If you’ve lost interest and we are on our own, please let us know.
Definitely have not lost interest! I've recently moved to CT though (the state not a cybertruk lol) and have been renovating the house. I'm actually about to finish picking up another trailer full of items to bring North, using my RV. Asking the Tesla to pull a 20' long cargo trailer is a bit much! :D

Hopefully I will have a few minutes to devote to this project again soon b/c the next few trips are likely to be with the Tesla and a 5x10 trailer instead, and charging every 60-80 miles b/c it won't go more than 120 on a FULL charge is less than entertaining when you have to disconnect every time. It might be free... But it isn't much fun.