Cable Sizing for Riggers

[RyanB]

Newb Question:

I'm installing two down riggers, which call 8 gauge wire for up to 15' and 6 gauge wire for up to 20' away, with a 30 amp breaker inline to the riggers. The instructions state to run everything straight to a battery, which I'd rather not do. My plan is to tie into an unused breaker on my 12V DC panel, to power a busbar, then run the dedicated cables to the riggers.

I'm new to running power through an onboard panel, so if I can get some advice it would ease my mind.

The largest wire currently in the panel is 8 gauge, with a 20 amp breaker, to power the fresh water pump. When I traced the wire, its spliced into a 10/2 wire about half way to the pump. All other wires running power out of the panel are 10 gauge.

Being that the manual for the riggers state to use 6 or 8 gauge, do I have to run a 6 or 8 gauge wire to the busbar to supply adequate power from the panel? The largest unused breaker is 20amp, which seems like plenty of amperage to me, but would obviously be the weak point with the inline 30 amp breakers the manual is calling for. Seems like overkill for down riggers.

Do I install a larger 30 amp breaker and run a similar size wire to the busbar, or is my 20amp sufficient?

 

[Play'N Hooky Too]

If the manual says use 6 gauge wire and a maximum 30 amp fuse, that means you need to have a 6 gauge wire circuit from the battery to the down rigger with a 30 amp breaker controlling that circuit. So yes, a 6 gauge wire from the battery to the buss bar. If you want to use a 20 amp breaker that is no problem from an electrical standpoint, but from a having-to-reset-the-breaker-all-the-time standpoint, it might get frustrating. The problem you are going to encounter running it through your panel is the size of wire supplying the panel. You may find that whenever you turn on the downrigger(s) the voltage drop at the panel is going to be significant. to the point that things might start shutting off due to under-current limits (electronics especially).

 

[RyanB]

The voltage drop of the panel is a good point and something I hadn’t thought of. I guess my reasoning is that absolutely nothing else is run off the batteries directly. Everything is through the panel.

 

[Bob Bradley]

I had a similar requirement on my 43C for a 30 amp deep drop electric reel outlet. Also needed a couple smaller outlets for a fuel transfer pump, underwater lights, and a chum chucker. I did a short run of heavy wire (4 or 6 ga - can't remember) from a sizeable fuse on my house panel to a new Paneltronics sub panel. From there, I was able to run 15, 20, and a 30 amp breakers as needed. I didn't run from the boat's main 12v panel up in the salon. It was a separate run from a dedicated fuse on the main house panel down in the engine room. That gives you a heavy gauge home run from the battery to the panel - about as close as you can get to wiring directly to the battery.

 

[RyanB]

I had a similar requirement on my 43C for a 30 amp deep drop electric reel outlet. Also needed a couple smaller outlets for a fuel transfer pump, underwater lights, and a chum chucker. I did a short run of heavy wire (4 or 6 ga - can't remember) from a sizeable fuse on my house panel to a new Paneltronics sub panel. From there, I was able to run 15, 20, and a 30 amp breakers as needed. I didn't run from the boat's main 12v panel up in the salon. It was a separate run from a dedicated fuse on the main house panel down in the engine room. That gives you a heavy gauge home run from the battery to the panel - about as close as you can get to wiring directly to the battery.

This sounds to be exactly in line with what I'm needing. By main house panel, do you mean the 12V Battery Panel in the engine room?

 

[Bob Bradley]

Yes, the 12v panel in the ER. Paneltronics makes a nice 8 breaker panel. I believe that they have breakers up to 30 amps for it. I'll try to take a pic of it later and post it.

 

[RyanB]

Yes, the 12v panel in the ER. Paneltronics makes a nice 8 breaker panel. I believe that they have breakers up to 30 amps for it. I'll try to take a pic of it later and post it.

Awesome, thanks for the help.

 

[Bob Bradley]

The bottom panel is the Paneltronics that I referred to. It is wired to a 100amp ANL fuse in the ER house panel that was not being used.

 

[RyanB]

View attachment 49040The bottom panel is the Paneltronics that I referred to. It is wired to a 100amp ANL fuse in the ER house panel that was not being used.

Thanks again, Bob. Exactly what I needed.