I measured a 3 way switch and I got two wires on 2 different screws measuring 120 volts. I thought only one should be hot??? I'm in a rush so I can't write a lot but if looking at the switch with screws were like this
c where c is the black screw
a b
I got voltage at "a" and "c" so I'm confused. I'll google later if that will help me but does this make any sense? I will try to explain more later as necessary. I may take the wires off the switch and just measure from the wires rather than from the screws on the switch, if that matters. I want to explain more but gotta run.