Originally Posted by DavidF
I am doing a shell off refurbish of a 1969 Caravel
18. Frame done, time for the first electrical job. First, running lights. I will be using LED lights only.
What gauge wire is best for the trailer cable?
Second, i will be running a separate line for the charging line from the alternator/isolator to a second connector and line to the trailer battery. Distance from the alternator to the connector on TV is 15 ft. Connector to the trailer battery will be either 10 ft. or 16 ft. I am thinking 6 ga. or 4.ga. Am I close? I'll appreciate any help.
Voltage drop was a problem in the 6V autos and trucks, by going to 12V
systems the issue was cut in half. Now we add the length of a trailer and the result is again a significant voltage drop. In addition small wire breaks easily. Here are my recommendations which go a bit further than the minimums you will see commonly used.
Even though you are using LED lights, for very little money you can use a wire that will be mechanically robust. For this reason use 12Ga, stranded, in a marine environment the wire would be tinned too, not a bad approach given the broad range of places you might go.
If you are talking about the trailer hitch connection, then you again would use 12 gauge, and then two 10 gauge for power and ground. I know you plan on a separate charge lead but why not keep things on the heavy side.
FYI, etrailer suggests lighter gauges wire, 3- 12 ga, and 4 -16 ga.