12 vs 24 volt ?

[PaulAlford]

I just bought a used Javelin and see that it has (2) 12 volt batteries next to each other for the trolling motor... and 2 separate red & black wires attached to each. So it appears this setup is for 2- 12 volt batteries. This is my first time running into this and thought this was setup for 24 volt (which would mean the 2 batteries would be connected TOGETHER... Neg from Bat 1 to Pos of Bat 2) Right ?

Why are these setup as 2 separate 12 volts? Does the trolling motor pull from both of these at the same time now ? I have no idea. Is there benefit to this separate setup over connecting the batteries together to make 24 volt?

Help !!

Paul

 

[RickJ6956]

Re: 12 vs 24 volt ?

Batteries in parallel have pos to pos and neg to neg. The voltage stays the same, but more amp hours are available.

Identical batteries in series have pos of one to neg of the other. The amp hours stay the same as if there's only one battery, but voltage is doubled.

Maybe the trolling motor is 12-volt only? Or the previous owner didn't want to deal with charging a 24-volt system?

 

[PaulAlford]

Re: 12 vs 24 volt ?

Thanks Rick. My 2 batteries are NOT connected to eachother in any way. There are 2 separate red/black wires coming from the boat - each connected to its own battery... so they are totally separated. I have never seen this.

 

[Silvertip]

Re: 12 vs 24 volt ?

DO NOT connect those batteries in the traditional POS -to- NEG series configuration as the boat apparently is not wired that way. Many older fishing boats were wired for either 12 OR 24 volt operation. Some had a switch panel up front labeled 12/24/CHARGE/RUN or some combination of those labels. There are 12 volt motors, 24 volt motors, and combo 12/24 volt motors. Boat manufacturers used all sorts of wiring schemes so before you do anything, follow the wires, make a diagram of what you see (or pictures) and THEN post back. Do nothing until you figure out what you have. Start by determining whether the motor is a 12 volt, 24 volt or both. How many wires from the motor to the troller plug in? The answer will be two or three. Does the boat have a switch/receptacle panel at the bow? If so - show us a picture. How many wires on the back side of the troller receptacle? Perhaps the answer to all of this is as simple as one battery is for the engine (the start battery) and the other is dedicated only to the troller (would would be a 12 volt version). But then maybe not!