Hi Jeff, I attended the Boat Maintenance Course with Norvan last spring and really enjoyed your talk. Thank you for that. I am doing some minor AC upgrades on our Tolly 37. I am replacing some old wiring with new, tinned wire (12ga). I want to insert the wires into the back of a GFCI. Is it OK to solder the ends of the wires?
According to ABYC, all connections between connector and wire need to be mechanical. Basically, you need to crimp the connector onto the wire. It does not hurt to solder the connector as well, but it isn't necessary. Soldering the ends of a wire for insertion into a GFCI will certainly make it easier. Since the set screw within the GFCI acts as the mechanical component, you are abiding to the ABYC standard and even going further.