Quite correct. If the solar panel is producing 10 amps then there will be 10 amps in both the + and - wires. What I was trying to imply is that the (-) amps does not have to go thru the GoPower regulator. I have all (-) wires in the battery compartment going to a single heavy brass stud. The total (-) current passing thru the GoPower regulator is only the power used to run its own internal electronics. It is still regulating the 10 amps on the (+) side as before.the + and - wire from the solar panel are both carrying the solar panel current. and the + and - wires to the battery are both carrying the battery charge current, so I don't understand your statement about minimal current at the 'ground' (negative side)
And to be concise, the (-) wire coming out of my diode switch box also goes directly to the brass stud as do the ground wires from the inverter and batteries, plus a wire going to the frame of the trailer. In other words, if it should be at ground then it is connected to the single stud. The GoPower negative connection(s) are no longer at true 'ground', but rather, float a bit above ground. (Which makes the display voltage incorrect by the amount of float, btw.)