thoughts on converting 12v trolling motor to variable speed

Discussion in 'The Projects Forum' started by nevets91, Sep 20, 2009.

  1. nevets91

    Thread Starter New Member

    Sep 20, 2009
    im thinking of converting my 5 speed foot control trolling motor to a variable speed trolling motor. my idea was to wire in some type of variable resistor in the the speed one wire, either a Rheostat or a potentiometer and mounting it to the foot contol so i can get those slower speeds.

    what do you guys think?
    do you guys know what size resistor i should use? i havent takin any measurements on how much amperage it pulls or anything yet.
    any help would be great thanks
  2. Wendy


    Mar 24, 2008
    How much experience in electronics do you have? You're idea sounds OK, you might even be able to find an aftermarket item that does exactly what you want.

    The reason I ask about electronics experience is there is another method called PWM (pulse width modulation), but it will require some soldering of small parts to make.
  3. nevets91

    Thread Starter New Member

    Sep 20, 2009
    i do have some experiance but not extencive. i have taken classes in high school and college so i have a grasp on alot of components but also my dad is fairly experianced in the electrical field and can help. as far as the pulse width modulation i dont exactly what that is but im sure i can figure it out if your willing to explain.
  4. GetDeviceInfo

    Senior Member

    Jun 7, 2009
    being an avid fisherman myself, I would put to you that dropping voltage over a resistor is an unnecessary waste of precious battery power. Just this spring in northern Saskatchewan while fishing for luner jack, we found ourselfs hampered in the weedbeds when we couldn't hold our position against a slight breeze, later in the day. Caught some great pickeral though.

    I would seriously look into a PWM controller.
  5. hgmjr


    Jan 28, 2005
    PWM is definitely the way to go. The use of a variable power resistor will waste energy and rob the motor of much needed torque right when you need it most.