BaitCaster said:
I'm going to be usig a bus bar when I finish wiring my boat. I will be wiring aerator pump, bilge pump and nav lights through the bar and a switch panel.
Is there any rules regarding wiring a bus bar? Does it matter where on the bar each wire is attached, or can I just connect anywhere?
Secondly, what gauge wire should I have running from the bar to the battery? Any other tips would be appreciated.
A bus bar gives you a point to attach multiple wires to one feed, as long as there is continuity from one end to the other, it doesn't matter where the wires are connected
Select a gauge of wire that will support the total current draw of all the circuits (plus 50%)and make sure you use a fuse or circuit breaker smaller than what the wiring could handle to protect it.
So if all the wires (load) will draw 15 amps when they are all on, and the wire from the battery to the buss bar is 15 feet, I would use a #10 wire (which will safely handle 25 amps) and use a 20 amp fuse to protect it.
Basically it should look something like this
BATTERY(Fuse or circuit breaker)----wire to buss bar------buss bar---fuse---wire to switch----switch-----wire to load------load
I posted in another thread a chart to figure wire size vs. load vs. length of wire
https://www.tinboats.net/forum/viewtopic.php?f=5&t=18499
The thing to remember is the fuse should fail before the wiring and the closer to the source (battery) the fuse is, the better.
Where alot of people go wrong is use too small of a wire with the wrong (or no )circuit protection.
