Enough juice?

[floatingwoody2006]

Just trying to figure out what i should expect for runtime from my current setup. I have a Minn Kota model 524 turbo pro bow mount troller. 48lbs thrust, 24 volts. I think i made a mistake when buying batteries for it, as i got a couple of the wallyworld group 24 batts at 75 amp hrs each.(all they had left) Im not sure how many Amps<br /> the troller draws, but i have been told that i should only expect about 3 hours or so trolling with them. I was under the assumtion that a 24v troller is more efficient in both the the hours i would get, and the wire could be smaller. I will also be powering a fish finder, bilge(almost never) and the stern lights at 12v for this. Did i make a mistake buying batts that are too small, or should i expect at least a moderate days trolling here?

 

[floatingwoody2006]

Re: Enough juice?

this is on a 280lb 14 foot lund also.

 

[Silvertip]

Re: Enough juice?

Are these deep cycle batteries, marine starting, dual purpose deep cycle/starting, or regular auto batteries? Depending on what type they are will determine run time. If that motor does not have Maximizer circuitry run-time will be relatively short but that all depends on how fast you troll and what type of batteries these are.

 

[floatingwoody2006]

Re: Enough juice?

Series 24 walmart brand everstart deep cycle only. They state 75 amp hrs on each one. Not sure how to know if i have the maximizer circuitry.. There is an adjustable "knob" on the top of the motor itself to scale down power.

 

[Paul Moir]

Re: Enough juice?

That trolling motor draws about 25 amps at 24 volts at top speed. So with 75 total amp hours, you would think you could run 3 hours (75/25) at full throttle. But that's not the case.<br />Lead acid batteries will loose capacity depending on how quickly you discharge them. At that sort of rate, you can expect to loose about 35%. So your 75 AH battery becomes 49, giving you just under a 2 hour run time until the battery is dead (10.5 volts).<br /><br />Now at half speed, the consumption will be half that, so you get twice the time. Actually you get a little more than that, because that 35% figure drops to about 25% since you're discharging the battery slower. If you could set it slow enough to use up the battery over a period of 20 hours, then you would get the full 75 Amp Hours out of it.<br /><br />Damage to lead acid batteries accellerates if you discharge them beyond about 50% of their capacity. So to maximize their life, you should try to stay above that number. That is 1 hour at full throttle or two at half. <br /><br />I'm not counting the running lights and such because they really don't amount to a hill of beans for this application. Not compared to the TM.

 

[floatingwoody2006]

Re: Enough juice?

so because i have 2 75 amp hour batteries i should expect pauls explanation to double right?.. About 4 hrs of half throttle and im still safe with the battery drain.. I hope im getting it..Probably not. Im half a moron sometimes, but it's all new to me. Thanks!!

 

[jtexas]

Re: Enough juice?

Nope - you have 75 amp hours at 24 volts - you would have 150 amp hours if you connected them in a 12 volt configuration, but then your motor wouldn't run.

 

[floatingwoody2006]

Re: Enough juice?

I guess im pretty dissapointed with that..And answered my own question. I did buy undersized batteries, but in order to troll for say 8 hrs over 2 days camping or something, i would need monsters. I am starting to think a 2 horse kicker would be a better route, but i would lose my foot controls. hmmnn..live and learn i guess. I will try trolling for an hour this weekend if i can to make my desicion. thanks again .

 

[18rabbit]

Re: Enough juice?

I think the prices are starting to drop on battery monitors. I can see folks with trolling motors benefiting from them. Basically what they do is what Paul did for you. It is a microprocessor that monitors the use of your battery and predicts how much time of batt use you have left based on your discharge profile. You tell it how many amp hours your batt bank is and it tells you how many hrs/mins of batt power you have left based on the way you draining your battery, that kind of thing.<br /><br />Like Paul said, the faster you discharge a battery, the less overall energy you can get out of it. A battery monitor takes that into consideration when predicting how much time your batt has before it is discharged.

 

[LubeDude]

Re: Enough juice?

Just to satisfy my own curiosity:<br /><br />You say troll, are you actually trolling or are you just using the motor to go along the bank as in Bass fishing? Honestly, bowmount motors are really not designed to just stay on for hours at a time, anyway I dont think they are. The transome mount motors Ive seen that are made to troll are generally a lot bigger motors.

 

[floatingwoody2006]

Re: Enough juice?

well, my 1971 rude is running now, but i know better than to trust it fully yet. I plan on going on a fishing trip in a very remote area in june, and will be staying for 3 or 4 days. I would like to think if i got into trouble, it would at least push me the 8 miles or so i needed to get across the lake. Plus moderate use staying off the bank during the trip. I know im asking alot, but i guess i didn't know all the limitations before investing. I didn't expect a wonders, but did expect more than 1 hour for a 460 dollar investment. Live and learn i guess.. Thanks

 

[jtexas]

Re: Enough juice?

That's all your walmart carries, or all they had in stock that day? You might be able to trade up to a bigger pair. If your walmart is like mine, you can take 'em back, at a time when automotive dept is closed, just tell the truth - they aren't performing very well, they drain too fast or whatever - they'll give you full credit no questions asked (within 12 months of purchase). Or carry a spare pair. Good idea anyway if you won't have electricity at the campsite.<br /><br />But - in an emergency - ignore the "don't discharge over 50% rule" - 2 hours at 3mph (unless your boat is v-e-r-y heavy) gets you close. And with a broke-down, you'd have the cranking battery - that'll give you a little more distance. Best be sure to fish upwind from your campsite.