I have an HP consumer-sized color laser printer. (M255dw). I plugged into a GFCi receptacle that protects outside outlets wired to its output terminals.
Every so often, it tripped when the printer started up. I unplugged everything else from the circuit; same result. I replaced the outlet. Same result. I called up HP, and said, 'hey, this printer has a ground fault'. The HP safety person and I were both a bit puzzled as to how this could be, but they sent me a new one.
Guess what happened this morning, which happens to be a damp morning here in damp Seattle. Printer started up, ground fault tripped.
What have we got here? Is there some reason why the surge current of the printer starting up would trip the ground fault? Or could there be a problem with the outdoor outlets?