I've run into several cases where a public charging station has power, but won't charge, apparently because of a wet or dirty connector. In my case, these were Sun Country Highway J1772 charging stations made by Clipper Creek, but I expect the problem (and the solution) applies to most/all types. This problem could show up as an error light (PROTECTION) or a chattering relay in the unit when you plug in. If you run into this, try spraying some electrical contact cleaner into the contacts of the J1772 connector, wait a couple of minutes for it to dry and try it again (and push the handle in firmly). This has fixed 2 for 2 non-working charging stations for me in the past week. Of course, there are lots of other problems a charging station could have, including no power to the unit, but this is a problem you might be able to fix quickly yourself. I'd suggest all EV drivers should carry a can of this spray - it could save you!