Re-wiring boat accessories

[lanyard]

I bought a used boat, and the previous owner was pretty handy with a roll of wire, electrical tape and crimp on terminals.

The problem is, EVERYTHING is a holy night mare and I want to make adds/changes/replacements. Can't tell one wire from another, and the terminal posts are stacked to the top with each and every accessory being wired directly... let alone trying to get it all to work again in the spring.

Is the bus board thing the way to go? I'm trying to figure out a good way to do this with a fuse panel type outfit, but the install side is beyond me at this point. No problem doing it, just looking for what I'm assuming is about 5 steps:

1) mount board

2) run wire from battery to board, use maybe a 4 wire

3) connect to board, then connect to battery

4) connect accessories to board

5) enjoy using lights/bilge pump/etc.

Any thoughts, ideas, experience very much appreciated!

[Whoaru99]

Basically that's it.

However, 4ga is a very large wire for just accessory loads - assuming you don't count an electric trolling motor in there.

You should always place a fuse or circuit breaker right at the battery to protect the run of main wire and the buss bar/fuse panel. The size of this fuse is determined by the size of wire you run to the buss bar/fuse panel. Generally, the buss bar/fuse panel will have a maximum load rating so the main fuse size shouldn't be any higher than that. Using large wire doesn't hurt, but it's not necessary if the load or length of run (excessive voltage drop) doesn't dictate it.

Then, assuming (and highly recommended) the panel has fuses or circuit breakers, size them accordingly for the wire gauge and load of the accessory.

If you take this approach, it would also be advisable to run a ground buss system too. Basically the same thing except you don't need any fuses, breakers, or switches on the ground side. Also, no fancy panel is necessary, just a simple buss bar strip with studs is all you need on the ground side.

[Eric Wettschreck]

I just got done totally re-wiring my boat, here's what I did.

1) Ran 12 awg THHN from battery to "Master Power" Switch via a fusable link.

2) Ran 12 awg THHN from "Master Power" to Main power block of the boats fuse block.

3) Ran appropriate wiring from fuse block, through swithes on console, to the various devices.....live well pump, bilge pump, lights, etc.

4) Grounded batteries to both the boat hull and the - side of fuse block.

5) Ran - wires for all devices.

[marine_man]

4) Grounded batteries to both the boat hull

I'm pretty sure it's not a good idea to ground your batteries to the hull boilerguy. It'll cause corrosion (electrolysis).

marine_man

[Eric Wettschreck]

Yup, I have learned from my mistake there. Thanks for the info.

I'll be changing that for sure.