Thread: 24V verses 12v for trolling motors

Originally Posted by strmwalker

its real simple ; amp usage !!!if we are talking electrical !!! now as far as moneys well that depend on where you buy!!!!

I must be really dense. A 24 volts motor requires (2) 12 volt batteries, right? Lets say each provides 100 A/H This combination will provide 1amp for 100 hours, correct?

Now lets put one of those batteries on a 12 volt motor (of the same thrust) that will require 2amp to get the same "power" (double right?). Now this (1) battery will provide only 50 hours of use, correct? Then we hook up the 2nd battery and this also provides us with 50 hours of use. So with the 12 using (2) batteries we get 100 hours and with the 24 using (2) batteries we get 100 hours. Which is more "efficient"? Both look equal to me.

Now lets use that (1) battery with a 12 volts motor and get 50 hours of use. Use that same (1) battery with the 24 volt motor and you get NO hours of use.

Originally Posted by blueball

i disagree,if your gonna do alot of trolling the 24volt is the only way to go.ive tried 12volt one bat,12volt 2 batt wired together,12volt with 2 batt and switch them out when one runs down,24 volt 2batt.,and now 2(4 batt) 24volt setups in my boat.with the 12 volt set up i had to run the trolling motor 75-100 % power to troll cranks,now with the 24 volt less than 50% power.MDCrappie do u do any trolling,if u dont u wouldnt understand how much the 24 volt helps,if u dont do any trolling and u have a aluminum boat a 12 volt is great and will work,just would waste my money on the 12 volt if i was gonna do any trolling.

No I don't do any trolling, but I do have a 20' alum boat with a 24volt electric motor. I have this due to the 12 volt not available in enough thrust.
I also have a 16' Alum and I have a 12 volt motor on that due to cost, and it is plenty adequate for it.


I'm thinking that your 24v motor is bigger then the 12v you originally had, right?

Now what do you think the difference would be if you had a 12v 55lb thrust motor vs a 24v 55lb thrust motor? Each having 2 batteries. Would you be able to run the 24v at 50% as compared to the 12v at 100%?

There is no 12 and 24 volt that have the same thrust so we are not comparing apples to apples here. I understand your arguement if they offered a 55lb thrust in both a 12 and 24 volt system.

Originally Posted by Handicrappie

There is no 12 and 24 volt that have the same thrust so we are not comparing apples to apples here. I understand your arguement if they offered a 55lb thrust in both a 12 and 24 volt system.

They use to make 12/24 and 24/36 trolling motors. I think the smallest (rated thrust) I've seen was 42 lbs.

Ya, I just meant they don't offer current models in one or the other so the comparison will never be equal. One of my buddies still has one of the 12/24 style motors.

Originally Posted by Handicrappie

There is no 12 and 24 volt that have the same thrust so we are not comparing apples to apples here. I understand your arguement if they offered a 55lb thrust in both a 12 and 24 volt system.

OK - here is the info that I can up with based on google

Minn Kota 55lb 12v motor draws 50amp on high

Minn Kota 80lb 24 volt motor draws 56 amps on High.

"In Theory" you should be able to run the 80lb motor at 68.75% to obtain 55lbs of thrust. If at full power the 80 lb motor draws 56 amps, it should draw 38.5 amps at 68.75%.

With (2) 100A/H batteries in series the 12 volt motor will (again in theory) run 4 hours. (4hr x 50amps = 200AH @12v)

With (2) 100A/H batteries in parallel the 24 volt motor will run 2.59 hours. (2.59hr x 38.5amps = 100AH @24v)

The advantage of run time goes to the 12volt motor in this case, the advantage of "higher available thrust" goes to the 24volt motor.

So to the O/P - if you determine that you will never be faced with a situation were you will need in excess of 55lbs thrust (max commercially available in 12volts at this time, to my understanding) then I see no benefit to purchasing a 24volt motor. If, however there is a possibility you might need the additional thrust then this is an advantage 24volts could provide.

NO! The 24v will run 5.19 hours. 200 AH divided by 38.5 hours equals 5.19 hours. You still have the same AH available regardless of how you configure the voltage. This is why 24v & 36v make up 75% market share. It's better.

Originally Posted by ATM

NO! The 24v will run 5.19 hours. 200 AH divided by 38.5 hours equals 5.19 hours. You still have the same AH available regardless of how you configure the voltage. This is why 24v & 36v make up 75% market share. It's better.

Sorry but your math is wrong. Batteries in series add voltage, amps stay the same. Batteries in parallel add amperage, voltage stays the same.

You still have the same available "power" (ie wattage) but not A/H. Google it, you'll see who's right.

24v and 36v make up the "market share" (not positive they really do as I haven't checked it) because back in the 70's a 17' boat with 150 was big, now they are 22' plus and these boats NEED that thrust to get them moving.