Comment by bluGill

J1772 is 120V or 208-240V. Those are by far the most common voltages in the US. (208 is what you get when you take a US 3 phase system and connect to two phases - this is somewhat common and most people don't know or care that their apartment is wired like that). I have seen other voltages at industrial sites, but I wouldn't expect that in a lamppost.