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This may be a dumb question, but I'm going to ask it anyway. I have a Minnkota 28 or 30 lb motor, it's small, but it still pushes my toon too fast to slow troll. Does anyone know how to slow it down so it won't use as much juice and I can troll slower for longer? I know I can put on a smaller prop or drag something, but I really want to only use half the ampage draw and turn things slower. So my battery will also last longer. It currently has a five speed control but it seems like the speeds are all about the same from 1.4 to 3.2 mph and the middle speeds don't make much difference they run close to the fast or slow speed. I'd like to find a .5 to .7 mph speed for the cats. Anything easy and cheap that can be done? Later J
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Have you considered a PWM (pulse width modulation) controller? It should allow you to accomplish both a reduction in speed and battery conservation. Not sure about cheap though. A 50Amp PWM on Amazon is about 75 bucks with shipping. There may be other serviceable units for cheaper.
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So how do you hook them into your motor, is it an internal part or external? Thanks for the tip that is probably what I'm looking for. J
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The PWM idea is a good one. It makes for a much more efficient system.
But if Cheap and easy are the idea, here are some:
1) Alter the prop. This can be done several ways including shaving it down, heating it and making it lower pitch, or switching it out completely using a low pitch model airplane prop (several have done this to gain more speed).
Altering the prop has several potentially bad consequences like lowering top end speed.
2) Use a 6V battery for your slow trolling outings. Half the voltage, half the RPM.
3) Switch a power resistor in the line for slow trolling. This will make your system more inefficient so you won't extend battery life, but you will decrease the power draw of the motor and decrease RPM.
My personal order of preference would be 2, 3, 1.
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Great tips, I'll have to study this out and see how they really work... I'm not sure about frequency in DC motors, just enough electrical knowledge to make me dangerous to myself... I was thinking frequency was more of an AC factor and voltage or ampage was the DC variables to try controlling, but I know they can control DC motor speeds these days... I'm sort of surprised it's as cheap as you found... Thanks for the tips, this is great... J
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Hey thanks for the input, like I mentioned I want to try and accomplish this without wasting my battery run time, in fact I'd like to double it if possible... I guess there isn't a way to wire a system so a 12 volt battery only shows half the voltage to the system, is there???
Think I'll study the PWM's and see if I can find a way to do that... I know they are about as expensive as the motor itself, but it would sure make the craft a lot more flexible for fishing options... I currently need all of my top speed that is possible, especially when the wind starts to blow, so I can't play with the prop or other things that can't be switched instantly and bring back full power... But I appreciate you opening areas to consider... Thanks J
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You could use a 12V - 6V DC to DC converter. In fact stepping down from 12V to 5V may be more common and move you even slower.
The probem I see just quickly surfing around is most are limited to 3-5A.
You'll probably want more like 20A for protection.
But the low amp ones would be enough to slow troll (on setting 1-2) if that is ALL you wanted to do.
I saw a few for under $10.
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Just as a note you can play around with the voltage to a point but when you start trying to run it way outside of where the motor is rated for then you can start doing damage to it.
I would check to see if the motor can handle the lower voltages first.
Another option might be to find one of the old little motors with a lower thrust rating.
Something like this.
[url "http://www.sevylor.com/12v-Electric-Trolling-Motor-P2063C45.aspx"]http://www.sevylor.com/12v-Electric-Trolling-Motor-P2063C45.aspx[/url]
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Found a deal on one.
[url "http://www.ebay.com/itm/Sevylor-12-Volt-Boat-Motor-/281837189845?hash=item419ece3ad5:g:5pUAAOSw~bFWKtFV&vxp=mtr"]http://www.ebay.com/itm/Sevylor-12-Volt-Boat-Motor-/281837189845?hash=item419ece3ad5:g:5pUAAOSw~bFWKtFV&vxp=mtr[/url]
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Thanks for the suggestion, I think that PWM looks like the right component for the job and there are a several for less than $20, but they do need some water shielding but I love the fact that you can get unlimited variable speeds out of it, within it's current min to max speeds... I know it will take some care to make it work in a water prone area, but it has so much potential I think I'm going to try it... Appreciate your efforts to get me set up thank you... J
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Hey thanks for your help and ideas on this as well... I think you're right about not taking things out of their designed load ratings and such, they tend to want to burn up on you... Anyway as you can see above, I'm leaning heavy to the PWM so that tech pulses the power on and off really fast and it sounds like it varies the length of on time and off time depending on how fast you want it to go... Sounds like it will work without harming the motor, so I think it's the best way to go.. thanks for the help.... J
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