Bilge pump wire

[mrdrh99]

Hey guys...I have a 600gph bilge pump. I need to extend the wires to a battery, I'll need to run about 10' of wire to get to the switch panel and battery. What gauge should I use? I was thinking 12g

 

[earl60446]

Just use the same size as the bilge pump has. 600gph is a small pump and 10 ft is a short run. 12 gauge is bigger than needed but it won't hurt
to use it.
Tim

 

[mrdrh99]

Cool... Thanks, I have some 14 sitting around somewhere. I'll use that.

 

[richg99]

This might help in the future.

https://www.westmarine.com/WestAdvisor/Marine-Wire-Size-And-Ampacity

richg99

 

[mrdrh99]

Thanks Rich...I made sure to bookmark that page

 

[DaleH]

Just remember, when using those ampacity charts, that a load 10' from the battery is a 20' circuit. Where you may have some wires go aft to the battery and forward to the helm switch, the advice is to measure the length of the longest run and double that.

600gph pumps run from 3 to 4 amps, typically fused with a 5-amp fuse, breaker or other circuit protection (remember, those are only there to protect the wiring from burning - not to protect the pump from potential damage).

I also use the 3% maximum volt drop calculator for my pump wiring, as I deem them critical accessories, but I boat on saltwaters, so my needs may be different than others on small ponds, etc.

Another 'tip' ... I seal any butt connector splices in the bilge with 3M 5200 and then put a piece of adhesive-lined heatshrink up over them. I size the HS to be > 3X times the length of the butt connector. And knock on wood, I haven't has any circuit (that I've ever rigged myself) fail in over 30-years of working on many, many boats.