24V vs. 12 V system and also value for autopilot

[Hoffer]

Hey guys-

Not sure if this should be in this thread or the boats/motors thread so you may see this in both areas.

2 quick questions.

1. Is there an advantage with a 24V system compared to a 12V system for trolling motors? Do you get more trolling hours with 2 batteries hooked up for 24V vs. having 2 batteries and hooking them up one after the other (when the first one dies switch to the other...).

2. Question 2 kind of pertains to question 1. I am considering an upgrade to an autopilot. Its a 2002 model and is a 65 pound thrust and 52 inch shaft and its a 24V system - so I would need to also buy a 2nd battery.

If I go with this used Autopilot - what do you think of 450.00 if its in good shape? I am debating that vs. 740.00 brand new at Fleet or similar stores.

Thanks for the input!!

Hoffer.

[remington 300]

the 24/12volt question really depends on what size boat your putting it on, 12 volt systems are adequate on boats upto 16 feet, and i say adequate for most fishing,wind and current will effect the performance alot, as far as more fishing hours for 24 volt system, same story, it depends on how high of thrust you need to run the motor, the higher the thrust,12 or 24 volt, the shorter the run time,

and as for the used auto-pilot for $450.00 that seem high to me, considering its 8years old already, the older auto-pilots had some issues if i recall, do you know the seller? i just traded a older minnkota 12 volt non autopilot for a little electrical work to my nephew,

i guess it depends on how bad you need a trolling motor, 450 would get you one but i think it would be a gamble, good luck with your choice,

mike

[Northlander]

Go 24 volt if you have room and your boat will handle the extra weight of that second battery. I love my out and co pilots. Wont own a boat with out them.

[Hoffer]

Hey Northlander-

Yeah for sure getting an autopilot - had one on my prior boat and loved it. I just dont know if the 450.00 is a little high for 8 years old...trying to weigh out the extra 300.00 for a new one. I just dont know for sure...

[walleyemaniac]

I have that same TM on my 17ft crestliner. It's an '87 so it's a heavier boat but that motor works great for me. The batteries last a long time because if it's not to windy I don't have to run it very hard, but it has plenty of power for my boat when the wind does pick up on the larger lakes. No complaints here. Oh ya, I did add the co-pilot cause my bother-in-law can't fallow a contour line to save his "you know what" and he's always the one in the bow.

I don't know about the $450 though sounds a little steep, make an offer see if they'll nab.

[Northlander]

Ya make a offer. $450 sounds steep here as well.

[PierBridge]

There are some good used deals out there right now as a lot of people are selling in order to get into a Terrova, I-Pilot set-up!

[dfv87]

Auto pilot is a must. I had and now don't on my new boat and man do I miss it...

I plan to upgrade back to 24 volts and Auto pilot... I have co pilot which helps but it is still way too time consuming.

[Hoffer]

Yup- I agree!

I had the auto on my old boat and I have fished my new one for a year now and I sure miss it. When its dead calm - or going with the wind - it isnt much of an issue. However, I was out the other day in a slight wind trying to troll upwind and stay on a weedline. The little wind there was caught my bow and kept pushing me in one direction or the other - and it was a constant adjustment on the foot control. With the AP - it would have still needed a few adjustments here and there - but would have been much easier!

[Hoffer]

so heres another question on the same front. I dont know much about electrical and all that.

My current system has an on board charger up front that connects right to the battery. It is a 2 bank charger with the other wires of the charger charging another battery in the transom. (not the starting battery...just an auxillary battery for the depth finder etc...).

So, can I simply add another battery up front and then connect the 2 batteries in a circuit and still use my old 2 bank charger? or is there such a thing as a "24V charger" vs. a "12V" charger? In otherwords would I need to buy a seperate charger too?

[remington 300]

one bank for each battery, no regard for the (jumper wire) for a 24 volt system. you can only charge two baterries with it total,probably the two for the trolling motor. the starting battery will charge off of the motor.

[BobT]

Quote:

1. Is there an advantage with a 24V system compared to a 12V system for trolling motors?

A 24v motor might give you a slight edge in terms of efficiency but my guess is that the difference in run time will be minimal compared to a 12v motor that delivers the same thrust and also using two batteries. The primary advantage of a 24v system over a 12v is that you can drive a motor with a higher rated output power without having to use mega sized wire to do it. When you get into the 24v systems is also when you start getting into the 55pd motors and higher. To run a 70pd trolling motor using 12v would require wire about the size of your thumb to handle the high current. By redesigning the motor for 24vdc, the current demand is lowered by half and so the wire size can be much smaller.

Quote:

Do you get more trolling hours with 2 batteries hooked up for 24V vs. having 2 batteries and hooking them up one after the other

As I already mentioned above, the 24v system might give you a small edge in efficiency so the total run time for two batteries might be slightly more than two batteries for a 12v system. My guess is that the difference will be miminal assuming all things equal.

You don't have to use one battery until dead then switch to the other. You can connect the batteries in parallel to deliver the same 12v but without the need to switch. There is a small risk in doing this. If one battery in a parallel wired circuit should by chance develop an interior short-circuit, it would likely damage the other good battery as well. I've had this happen before. The bad battery created a short-circuit condition for the good one and they both had to be replaced.