What size wire

[18Starcraft]

I am rewireing my 18 Ft aluminum CC. Nothing worked, switches were bad and I found cracks in the old wire. I have to run 4 wires back from Console switches. 2 for Bilge Pump with auto float switch and for 2 for lights. run is only about 10 ft. Wire will go under floor. I noticed the wire I used on my old F/G boat had "Impervious to Gas & Old" was 12 gage.

What size wire should I use? Thanks

 

[WAVENBYE2]

Re: What size wire

Most of the wires in my boat are 14 gauge, for the bilge, fuel pump, blower etc.. I would think that would be ok, Yhe bigger the wire I believe the more amps you would need. But I would think 14 would be good, Just my opinion, What gauge wires are the things your hooking up??

 

[Tubingluvr]

Re: What size wire

I always use 12 gage for any wiring in my boat, better to have too big than too small.

 

[WAVENBYE2]

Re: What size wire

Most of the wires in my boat are 14 gauge, for the bilge, fuel pump, blower etc.. I would think that would be ok, Yhe bigger the wire I believe the more amps you would need. But I would think 14 would be good, Just my opinion, What gauge wires are the things your hooking up??

I forgot to mention that mine came from the factory that way.

 

[allpoints360]

Re: What size wire

Some recommend 10 gauge for accessories, but 12 should fine.

Good luck.

 

[Jeep Man]

Re: What size wire

14 gauge will work, but 12 is better. Solder and heat shrink your connections. Look for extension cord type cable with SJOOW on the side. This is rubber jacketed, rated for outdoor use and is impervious to oil, water, uv, and cold temp.

 

[actionljackson]

Re: What size wire

14 gauge is what you will want to use.It will depend on what it is your running with those wires.10 gauge on accessory switches is overkill.

 

[Woodnaut]

Re: What size wire

I used all "marine grade" wire on my boat. I know its more expenseive, but the insulation has good resistance to oil and gas, the the conductors are "tinned" which make them much more corrosion resistant.

 

[jlinder]

Re: What size wire

Most of the wires in my boat are 14 gauge, for the bilge, fuel pump, blower etc.. I would think that would be ok, Yhe bigger the wire I believe the more amps you would need. But I would think 14 would be good, Just my opinion, What gauge wires are the things your hooking up??

Bigger wire does NOT require more amps. It has no effect on current draw. (Actually, if you have a long run and smaller wire you get a voltage drop - lower voltage the the device. In the case of a motor you can be drawing more current).

I didn't see it mentioned, but you of course need stranded wire - boats have a lot of vibration.

Also, as mentioned you need to do the connections up right. Seal them well to prevent corrosion

 

[scbackpacker]

Re: What size wire

Get a copy of Ugly?s Electrical References by George V. Hart. It is a good guide to electrical formulas and also has wire ampacity tables in the rear of the book. Parallel circuits and series circuits are different in voltage drops and amperage across each device. As everyone had said you want to use stranded wire. I think another good wire type would be multi conductor tray cable. We've had this cable installed in our plant for over 25yrs. ran in cable trays outside from building to building and never had a problem with it. I would think 14 ga. would plenty big enough but that depends on the type of wire you use and the current draw of the device. Be sure to size the fuse block feeder big enough to carry the total load of all your devices installed. If using wire of the same color get a booklet of wire numbers and number each wire on both ends with the same number using different numbers for each wire. It makes it easier to hookup and trouble shoot later if need be. Make a diagram of your circuits writing down the wire numbers used for what device and keep it put up to help out later to trouble shoot.

 

[jlinder]

Re: What size wire

scbackpacker makes an excellent point. Document, document, document. When you go back later to add something, or fix something it will be worth its weight in gold.