24V vs. 12V and also a question on Autopilot value

[Hoffer]

Hey guys-

Not sure if this should be in this thread or the equipment 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.

[delcecchi]

60 percent of new seems like a lot for an 8 year old motor, unless it hasn't been used much. That is just my opinion however.

[CAMAN]

I will never go back to a 12 volt. The extra power is more than enough reason to go to 24. If you're going to have the weight of 2 batteries for a TM then why not use the full potential of both those batteries?

In regards to the new vs. used, the autopilots have some very sensitive computer chips inside of them and they do go bad. $450 seems pretty steep for an 8 year old motor, who knows what is/could go wrong with it and how they were treated before you bought it. $250 seems like a fair price for a motor of that age. Then you would have a little breathing room from the new price if something were to go wrong with it.

[Hoffer]

Hey guys-

Thanks for the input!

Sounds like the 450.00 is a little steep and that is what I was thinking too.

I amy just wait and try to pick up a new one..at least I know it will be under warranty and I wont be shelling out anymore for awhile. If it was 100.00 less or 2 years newer - I would go for it I think. But its just a stretch away from being in the right ballpark.

[solbes]

Autopilot is awesome. I've had both and I really enjoy the AP that I have now.

Can't comment on the 24 volt setup since I've only run 12V/55#'s on 16 foot boats. I would think a 55#/12V would work fine on just about any 16 foot aluminum boat and smaller. You can hook them up in parallel to double the capacity. 24 volt setups are great too though if you can afford them.

$450 is a little high for that vintage, but I would say somewhere around 350-400 would be where I would price one. One benefit of a new unit is that someday you could upgrade to the I-pilot feature with Version 2 powerdrives. A 2002 model would not accomodate this.

[SkunkedAgain]

Remember that you can always offer less than what the seller is asking. Figure out what you are willing to pay and offer it.

[BobT]

Quote:

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

Yes and no. The primary advantage of a 24v over a 12v is wire size. With both motors rated at the same output power, the 24v motor will allow you to use smaller supply wires because it will demand lower current.

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 (when the first one dies switch to the other...).

Yes and no. Thrust and horsepower are not interchangeable. My gut instinct and electrical background suggests to me that given one motor with dual voltage rating of 12/24, wired for 24 or 12 will make no difference in total run time on two batteries. However, because thrust and power are two different things then two different motors rated for the same thrust but different voltage may result in different run times. Kind of hard to explain but there are power/torque/thrust curves that come into play and I lack the engineering background to explain it. Maybe you'll get slightly more run time using a 24v motor due to increased motor efficiency but my guess is that you probably won't find any real significant difference.

To run a 24v system will require two batteries connected in series unless you find a 24v battery. For a 12v system you can connect both batteries in parallel but there is a potential disadvantage. If one battery develops an internal short circuit, it will overload the other battery and damage it as well. Not a likely scenario but could happen. I've experienced this in a diesel truck one time.