Re: Cable gauge size for 20' run
Posted: August 2nd, 2019, 6:30 pm
Ensure that if you were to max out all the loads, that the bus bars would handle the total, there's a variety of ratings out there. And remember that the length of the circuit includes the distances from the source to the load and back (neg & pos), not just one way.
It should also be noted that if you keep adding negatives to your blocks, you must ensure that the main block negative cable that was original to the build from the block to the batteries is capable of handling the current from all the extra loads you've utilized the block for as a negative terminal. Same applies to adding additional loads to a bus bar, the main cable connecting the bar to the source needs to be of sufficient size. Installs often fall short here. They'll install a 100 amp bus bar for example but hook up a cable to the battery that can't handle 100 amps. Need to consider the entire circuit.
BTW, run as large a wire as practical to the helm. You'll likely be glad you did in the future, and running 1 or 2 sizes larger won't be that much more difficult to do. What will be difficult is doing it all over again because you have insufficient power for the new toy that hits the market in a few years and you just can't do without, and have the admiral's permission to get
It should also be noted that if you keep adding negatives to your blocks, you must ensure that the main block negative cable that was original to the build from the block to the batteries is capable of handling the current from all the extra loads you've utilized the block for as a negative terminal. Same applies to adding additional loads to a bus bar, the main cable connecting the bar to the source needs to be of sufficient size. Installs often fall short here. They'll install a 100 amp bus bar for example but hook up a cable to the battery that can't handle 100 amps. Need to consider the entire circuit.
BTW, run as large a wire as practical to the helm. You'll likely be glad you did in the future, and running 1 or 2 sizes larger won't be that much more difficult to do. What will be difficult is doing it all over again because you have insufficient power for the new toy that hits the market in a few years and you just can't do without, and have the admiral's permission to get