Thread: infinite speed control switch

I have a 30-pound, 5-speed Minn Kota trolling motor. I'm wondering if there is an electronic part I can put in the circuit that will allow me to have more control of the speed between off and the first speed.

Here's a potentiometer that I'm thinking will do the job: MLCS router speed control and Foot Switches

I know this device is set up for AC, but will it work for a 12 V DC motor? Any thoughts appreciated!

Thanks!

I know someone that tried and failed to regulate their trolling motor like that. The regulator didn't help any to lower the speed between selector switches. I think he finally got it to work when he too out the selector switch and rewired it but still didn't have any control of the first step up. Guess the motor was simply not meant to go slower than the first step.

Only thing I can think of to get a slower speed any other way would be to get another prop in a different pitch.

I've wondered about this myself. My guess is that you have a bunch of high wattage resistors in series and you are just simply tapping off a different resistor every time you turn the handle. Unfortunately, the resistor bank is generally enclosed in plastic. Even if putting a high wattage resistor in series with your battery wire was a solution, the question would be what ohm value resistor. I'd be curious to hear others input.

I think you would be wasting your money on that controller . It's made to control AC voltage. Canepole would know for sure..

Forget the AC controller. It won't work. AC speed controls use a totally different method. Look on eBay for a Maximizer from Minn Kota.

Ebay has pulse width modulators (PWM's) for sale. This is what you need for a DC motor.

http://www.myskunkworks.net/servlet/...-PWM-DC/Detail

You can use one of these boards to build your own. I built one once using a 40 ampelectric wheelchair control board. I used the 40 amp because my motor was fused 40 amp. Its a 70 lb. thrust.
You should check the max load your motor is capable of however for a 30 lb. thrust that board should be ok.
The Minn Kota Maximizer would be the best way to go if you can find one at a reasonable price. I never could find one so I made my own.

If you have wiring and soldering skills, I can help you build one. If no skills, go with the maximizer. Don't burn your boat up by guessing. MOAO

Originally Posted by Cane Pole

If you have wiring and soldering skills, I can help you build one. If no skills, go with the maximizer. Don't burn your boat up by guessing. MOAO

I'd be curious to hear your solution.

I have built numerous speed controllers using wheel chair pwm and have purchased PWM circuits from the robot store. Either circuit can be rigged for speed control using a 5k potentiometer. I have built several and waterproofed them. I put the pwm circuit in an old car stereo amp box and used the amp box for the heat sink and board container. Got the amp box at a yard sale. I sealed the unit using RTV silicone. Power in and power out was pigtails...I made custom end plates from sheet aluminum.

Ebay has some pwm circuits (china) but I have never use them. I have used 4QD circuits in the past.