No, you need a circuit (like what is in the OpenEVSE box) to generate the J1772 pilot signal for the car to agree to charge at 240V. Although It would be a waste of such a heavy cable, you could attach normal 120V (NEMA 5-15P or 5-20P) plug and the car would charge at 16A. The car does not need a pilot signal if it sees 120V, but requires the pilot signal if it sees 240V. I know this because I tested hooking up 240V to the smaller-gauge, yellow 120V charge cable that came with the Roadster.I've got a dead cable like this too. If I cut the wall plug / GFCI end off like this one, could I just wire on a 240v plug and charge? How would one use the cable and car plug end only?