Whelp. With CCS dying in the US. We *really* need OpenEVSE to source an NACS cable or connector for existing OpenEVSE units.
Just opening the discussion. :-)
I've been holding off on buying an OpenEVSE for the past few years as I waited for someone to start selling a NACS cable. As soon as I heard that Tesla had opened the standard for NACS, I figured that might finally be the catalyst for someone to offer the cable. Now with Ford and GM (and likely more to follow) saying they'll use NACS, the ball is well and truly rolling. Does anyone know how much longer we might be waiting for a cable?
I've been tempted to buy a salvaged Tesla mobile connector from eBay to use the cable, but they're all so expensive for something that doesn't work, particularly considering their relative cost to purchase brand new. Plus, I'm a little hesitant to re-use something that may be damaged in a high voltage/amperage application.
Technically, there's no reason a NACS cable can't wire directly up to an OpenEVSE unit. Tesla converted them over to more standard J1772 / CCS signing a few years ago.
However, the supply of NACS cables is non-existent at the moment. Nobody is making them (which is a bit concerning with this industry shift).
We really need a supplier to step up. Obviously if your vehicle has a J1772 / CCS plug, it doesn't make sense to source an OpenEVSE with the NACS connector... however in 2025/2026 this is supposed to shift rapidly. OpenEVSE should be ready.
OpenEVSE will offer NACS as soon as we can find a supplier. Tesla cables sacrificed from a Tesla Mobile Connector or HPWC work perfectly on OpenEVSE.
Don't those NACS connectors handle AC or DC depending on the evse or charger? seems dangerous to not totally isolate the AC and DC connections like a CSS does.. You are putting a lot of faith in the vehicles onboard system and evse playing fair with each other. or contactors not to get stuck, etc.
@Pir8radio The plug does not really matter, NACS (Tesla) or SAE J1772 with a Tesla adapter. They are electronically and pin equivalent. Tesla seems to have it figured out, every Tesla vehicle shipped in North America uses the same pins for AC charging via NACS and J1772 or DC supercharging.
I would assume non-Tesla OEMS would have to comply with the same standards for their onboard charging systems to use Tesla Supercharger network and NACS socket.
I have been using a Tesla plug on my personal station since 2012 without issue.
@pir8radio Are you saying Teslas should not charge on AC charging stations?
Tesla has been using the same pins for AC/DC charging since The Model S was released in 2012, we are not aware of any issues with DC from the vehicle damaging AC charging stations. 10 years and 4.5 million vehicles would seem to be a pretty large sample size.
We are not experts on the Tesla DC system but, we are aware that there are physical contactors in both the vehicle and battery. If the vehicle system is anything like the charging stations, then a DC fault would force the vehicle to open the vehicle and/or the battery contactor. I would be shocked if Tesla did not think this one through.
NACS level 2 is electrically identical to J1772. People today use OpenEVSE units with NACS / Tesla cables without issue.
*however*, as NACS was proprietary, few to no NACS cables / handle vendors exist today. (check yourself, you can find tons of vendors selling J1772 components, but almost zero Tesla / NACS cables / handles / etc.)
As soon as 3rd party components become a thing, I'm sure OpenEVSE should be able to support native NACS cables.
Electric Ant, Make sure the wires leading from the control board to the connector are the correct gauge for the amperage.
I opened a ticket with the OpenEVSE team, I'm working with a team in Ohio who is interested in developing a NACS connector, support from OpenEVSE would be helpful.
another thing I was thinking, with the J3400, aka NACS, the tesla version uses CAN bus to relay info from the car to the supercharger so the network knows who's Credit card to charge (that you have on file with tesla). CAN traffic isn't encrypted, so all someone would have to do is stand up a few "free" chargers and skim the users info from the car CAN bus traffic or create a handheld simulated EVSE so the tesla gives up that info, then emulate it on a reprogrammable converter cable (small extension) man in the middle, then one could emulate the recorded vin or whatever data is sent via the can bus to the supercharger and basically perform credit card fraud by stealing free supercharging. Elon jumps into things too quickly without planning for the long term future. I do like the connector, but some things need to be fixed or cleaned up in the standard first. I wouldn't use the unencrypted can traffic to handle user tracking especially since it effects a users wallet.
Are you sure that’s how billing happens? I read that the car sends billing info via the car’s cellular modem which is encrypted. Only vin number is sent to supercharger.