skinny on 24v trolling

[lanyard]

Howdy,

Been awhile since I needed to worry about trolling motors and I know there has been a ton of changes.

Do 24v trolling systems require two batteries? Is there a benefit to power if you go with two vs. one?

The one being purchased will be a MinnKota.

Thanks!

[Fishin4Life]

I do know that it does require two batteries. As far as power, I can't answer that. What model minnKota are you looking at? Maybe that could help for people that own that model, or possibley suggest a better one...etc

[solbes]

You do need two batteries for 24V systems. I personally have a smaller 16' boat, so a 55 lb thrust, 12V system works great. I don't do a lot of fishing on big water either.

If you have a bigger boat and/or spend a lot of time trying to hold position in windy conditions, then you should look at the higher thrust ratings which are typically 24V systems. Double the voltage will cut the current draw in half, thereby allowing your batteries to have much longer capacities.

[BobT]

The advantage and probably the reason for using 24v systems on the larger thrust motors is because a 24v motor can acheive the same horsepower with less current draw. This allows for smaller wires. My 40pd Minnkota uses 8ga wire to handle the current demand which can be as high as 42A. If this motor could be rewired for 24v, it would only use about 21A max to acheive the same power output. The wires could be much smaller.

Bob

[Guest]

You need 2 batteries. You will have more consistent power, and much better run time with a 24v motor. They will hold up to the demands of fishing on choppy water, and they will run forever on calm water.

On higher thrust settings, you have about twice the run time of 12v motors(calm water), on rough water the 24v system will run way longer because you are not forced to run it as hard as the smaller motors to acheive boat control(much longer battery life in rough water). On lower settings, you will putt around all week with a 24v motor.

If finances allow, and you fish more than a few hours at a time.. buy a 24v motor and a couple decent batteries and you will not be dissapointed. Models with the maximizers are best, and get much better speed control.

[lanyard]

Thanks folks, that's exactly what I was looking for. Doing leg work for my brother in-law who is in Iraq right now. He got a little surprise- his company had instituted a reward system for sales, etc. that funded without his knowledge! The points are redemable at Cabela's!

Appreciate the info.

[dfv87]

Sounds like a great company! Hope your Brother in law gets home OK, We will all keep him (and all the soldiers over there /everywhere) in our thoughts and prayers.

[countryboy9799]

Just wanted to point out that the run time would be about the same as 2 12 volt batt's hooked in parallel.

[mtreno]

i disagree -

you are still drawing more power with the 12 volt - yes two batts will last longer than one but i still think a 24 volt system will last longer. just does not need the same amount of power to run.

think of it this way - you need 1/3 power on your 24 volt system to keep fishing in the wind - spred out over two batts - the same fishing conditions you need 2/3 power on your 12 volt motor to keep up - thus drawing down your 2 12-volt batts faster - adding an extra battery to your 12 volt system will not increse power of the motor itself

i could be wrong but thats the way i look at it

[countryboy9799]

I think its more like this,

Power is the same thing as watts

volts X amps = watts

I will use Bob's amperage listed above

42 amps X 12 volts = 504 watts

21 volts X 24 volts = 504 watts

I think its fairly close to comparing elec. motor's for AC, you will still use the same amount of power whether using 120 volts or 240 volts. Voltage drop will be less for higher voltage with the same size wire though so it will help a little.

Unless I am missing something and you can explain how come a 12 volt needs more power to do the same job as a 24 volt?

[Norco]

I had a 40 Pd Power Drive (12 volt) on my SSV 14 and it easliy lasted a full day. On windy conditions I a;ways used the wind to my adnvantage with drifts socks.

I know have a 70 lb Power Drive (24 volt ) in my 1800 Fisherman and it can go 3 days with out a charge. I got a pair of Trojan batteries and have been smiling since.

Cheers!!

[eurolarva]

Country boy is correct with his power formulas. 24 volt motors can go twice as fast as a 12 volt motor however it will burn energy twice as fast. Also 2/3 power at 12 volts is 7.92 volts and 1/3 power at 24 volts is also 7.92 volts. The only thing a 24 volt motor is going to get you is more thrust. On a 12 volt 35 lb thrust motor is rated for 14 hours on position 1 where you will get 28 hours if you have two batteries. Chances are you will get similar results for the same speed out of a 24 volt system.

[Guest]

You guys debate it, I'll just troll right past you when your battery(s) go dead(no pun intended). Thrust has a lot to do with it also. A 40# 12v trolling motor full throttle is going to run for 2 hours, a 80# thrust 24v motor at 1/2 throttle (40# thrust)will run for 8 hours. You have to take in to consideration diffrent motors and larger props, and also the load your motor is pushing. If you are underpower... your going to use a lot of extra juice, if you are over power, its compensated for with a lower speed setting and there is very little wasted energy. All Minnkota motors will have a top speed of about 6 mph whether they have 30# thrust, or 101# thrust. If the motor is only capable of pushing your boat 2.2 mph.. your motor is working hard and will be far less efficient, if you are capble of reaching 4-5 mph, you will operate much more effieciently at all speed ranges... or your going to fish a heck of a lot longer with a trolling motor set on 15% to hold position and your desired fishing speed on a windy day than speed 3-4 on the less powerful motor. to fish with the same control and speed.

I am just speaking from experience here. I used to fish the city lakes(trolling motor only) and pull shad raps 5 days/week. I started with a 36# motor, then upgraded to a 40#, then the 50#, and finally I upgraded to a 65# motor. The 36 and 40 pound thrust I could only troll for 4 hours with 2 batteries(group 29) and I had to make a run for the access.. still ended up paddling more than once. The 50# was much better, I could troll 5 hours and *limp* back to the access... this was on a 14' bench type boat(very light). The 65# motor mounted on a 16' boat now(considerably heavier) I have never run out of juice yet. I have trolled as long as 7 hours averaging about 1.6 - 2 mph and still had 30% power left at the end of the outing.

Its very nice getting on the water and having one less thing to worry about... dead batteries are no fun, especially when your on trolling motor only lakes.

[countryboy9799]

Like you said you were not comparing equal motor's.

The minnkota ad's I have read is that the cheaper one's are more likely not to have the maximizer feature on them, maybe yours didnt? The ad states that it will run 5 time's longer with it, dont know if that is true or not though.

Maybe you can post some effeciency chart's to say that a 40lb thrust is not as effecient as a 80lb running at half throttle.

With all that said it's really watt's that get the job done, effeciency of the motor will make a difference though.

[Whoaru99]

Yup, a watt is a watt regardless if it's a "12 volt" watt or a "24 volt" watt.

If it takes 40 lbs of thrust to move your boat "X" MPH, it requires "Y" amount of power to do so. I don't follow where the difference would come in between a 40lb motor running at 100% and a 80lb motor running 50%. They are both putting out 40lb thrust and that requires a certain amount of power. As I see it, only if one or the other has a significant efficiency advantage (e.g. Maximizer vs. non-Maximizer) should there be a significant edge in run time.

If the two motors were essentially equal in all regards except 12 volts vs 24 volts, the 24 volt probably would have a slight efficiency edge. But, that edge is not going to be like a night and day difference. I'm just speculating on this but I'd say perhaps 5% or 10% advantage to 24 volt system.

[Valv]

Regardless of speculations, thoughts, calculations, and theories you cannot get any motor above 55lbs and 12volts.

65lbs and up are all 24 volts, and 101 and up 36 volts....

A 12 volt motor is made for a smaller boat which can accomodate just 1 battery comfortably (weight and endurance), the 24 volts are for larger boats that can accomodate 2 batteries comfortably, then 36 volts are for very large boats that can accomodate 3 batteries.

[BobT]

I would bet that a 55pd 12v motor will come with very large supply wires. Probably in the 6ga category or larger. Make a motor any larger than that in 12v and you are likely to have some massive wires. Redesigning the motor for 24v provides the same power consumption with half the wire size. Much less costly to build.

Bob

[solbes]

That's a good point on wire size. I had to rig my 12V 55# with 6 gauge wire to avoid voltage loss through the wire. Not too bad of an expense though.

It comes down to boat size and intended use. If it's any larger than 16' and/or heavy then go with the 24V. Also if he fishes windy conditions while trying to hold position (Mille Lacs,Leech, etc), then go for 24V.

[Whoaru99]

True Valv.

I think somewhere along the lines, the OP's question got expanded into "does a 24 volt motor (needing two batteries, of course) run longer than a comparable 12 volt motor connected to two batteries". I believe the answer is no, not significantly, all other things being equal.

If the OP has room for two batteries, and needs that much thrust potential, then sure, 24 volts is the way to go.