I would be very careful when selecting large gauge cable. There was one post where the guy thought he was getting 2 gauge (for example) but none of the 2 gauge lugs fit. It turned out to not be real 2 gauge wire, more like 8 gauge. I used welding cable from TEMCo Industrial, along with lugs from them and everything fit together nicely.
With regard to wire color, if you're making long runs that can be hidden, using two colors is just easier. For the low amp wires in my RV trailer, in many cases the colors are random. Sometimes both wires are the same color. I have to pull out my voltmeter to determine which wire is positive and which wire is negative. For some devices, it doesn't matter which way you connect the wires. But that's the exception rather than the rule.
My ground bus bar is probably 100 amp, while the common bus bars are both 250 amps. I used 10 gauge wire from the inverter, solar charge controller and converter to the ground bus bar.
With regard to wire color, if you're making long runs that can be hidden, using two colors is just easier. For the low amp wires in my RV trailer, in many cases the colors are random. Sometimes both wires are the same color. I have to pull out my voltmeter to determine which wire is positive and which wire is negative. For some devices, it doesn't matter which way you connect the wires. But that's the exception rather than the rule.
My ground bus bar is probably 100 amp, while the common bus bars are both 250 amps. I used 10 gauge wire from the inverter, solar charge controller and converter to the ground bus bar.
