12 or 24 volt ?

[licketdsplit756]

1984 ranger bass boat w/115 hp johnson outboard. the trolling motor is 24 volt. if i wire up the trolling motor along with the boat motor. im using 2 batteries. how do i do this so i dont use 24 volts to the motor for the 115 just to the trolling motor. or do i need 3 batteries 2 for the trolling motor wired to 24 volt and another just for the 115 hp..

 

[HighTrim]

Re: 12 or 24 volt ?

If you connect it positive to positive (hot to Hot) and Negative to Negative (ground to ground) you will have double the amps but sill only 12 volts. If you connect it Negative to positive and use the other ends as the terminals, you will have 24 volts and I THINK 1/2 the amperage.Do you have a 3rd white wire, I believe if you do you need to check with the motor manufacturer to verify wiring instructions. However, I think what you will find is that you need to undo the current battery wiring. Connect the two NEG terminals together. The white wire from the motor connects to either NEG terminal. The BLACK wire from the motor connects to the POS terminal on one battery and the RED wire from the motor connects to the POS terminal on the other battery. You essentially are feeding two separate 12V sources to the motor. 24V is being taken care of in the motor. Without knowing the motor type, this is speculation on my part so make sure you verify this.

 

[licketdsplit756]

Re: 12 or 24 volt ?

thanks high. im wondering if the boat motor its self will run on 24 volts.if it has to be 12 then im for another 70 dollar battery to run the trolling motor.

 

[Barnacle_Bill]

Re: 12 or 24 volt ?

NO, the boat motor will not run on 24V. You would be much better off and safer using 2 batteries for the TM and one for the motor. Using just the 2 you are subject to running out of cranking amps and have to start it by hand.

 

[iwombat]

Re: 12 or 24 volt ?

You could just make a voltage divider. It requires 3 resistors. Probably a pretty easy google search.

 

[Silvertip]

Re: 12 or 24 volt ?

Forget running a 24V trolling motor using the starting battery and one additional battery (unless you have a set of oars and a buddy along). The trolling motor will run down BOTH batteries and will very likely leave you stranded since neither battey will start the engine. If you did decide to do this, you would connect the engine to one battery normally. Then off the positive terminal of that battery, you run another cable to the NEGATIVE terminal of the second battery. Then connect the trolling motor to the NEGATIVE terminal on the starting battery, and POSITIVE terminal of the second battery. The trolling motor then runs on 24V and the engine sees 12V as normal. The only glitch in this system is the engine will only charge the starting battery. And just so you know, you would have to run wide open for a long time to charge a deeply discharged battery.. The best bet is to install two deep cycles in series for the trolling motor. Add a two-bank on-board charger to charge the troller batteries when you are at the dock. Leave the engine start battery for the engine and accessories. Getting "creative" with batteries only leads to potential problems. The vast majority of the fishing rigs on the planet are wired using separate troller batteries.

 

[57whitehouse]

Re: 12 or 24 volt ?

is there a cheap 12v trolling you can get? you probably won't be able to charge the 2 trolling motor batteries off the gas motor unless you unhook them and charge them seperatly and one at a time. unless you plan on going back to shore after the 2 trolling batteries are dead.