# Dc Treadmill Motor Controllers (what Are My Options?)



## reventropy (Aug 1, 2015)

I recently purchased a Treadmill motor from ebay with the intent of upgrading the motor on my mill. The motor has the following specs:

H.P - 2.5
Volts - 90 (DC)
Amps - 17
Duty - Cont.
RPM - 4700

I am having trouble specing out a controller for this motor which I find strange considering how many similar treadmill motors are available.  The best option I've found so far is the KBMM-225D.  I would link to the data sheet but the spam filter doesn't like it.

I could run this with 230 volts and jumpers set to:

180 volt output - Wouldn't this half the HP rating and double the speed?
90 volt output - Would only get 1.5 hp out of a 2.5 hp motor? (but.. 16A*90V >1.5hp.. hmm)

Do my assumptions seem correct or is my logic off?  Any tips or links to a more suitable driver would be awesome.  Thanks!


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## Ulma Doctor (Aug 1, 2015)

a MC60 controller that were commonly used in treadmills (ICON,Nordiktrac,etc.)
would suffice, as long as
you were so inclined to add your own speed control potentiometer and do some wiring.
you can find them used for about $60(+shipping) or so on ebay

i could help you wire it up if you needed some help


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## mattthemuppet2 (Aug 11, 2015)

any of the MC controllers should work although it would be worth doing some research into the max HP the cab develop given that most TM motors are around 1 to 1.5hp. going through the same thing myself right now with my lathe and DP - there's a thread on here detailing my "discoveries"


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## reventropy (Aug 12, 2015)

Thanks for all the input.  I could not find any specs on the MC controllers as pertains to current draw and the little I could find makes it look very similar to the KBMM225.  Also, at the time of the post I had already bought the KBMM225 and was considering returning it in favor of a better option.  I finally ended up using it and it drives the motor just fine without getting hot.  I guess the problem is that now I'm running a 1.8kW rated motor at something like 1.1kW (not under voltage, but current limited).  I could connect it using 240V and gain enough for 3 horses but that's at 180 volts, so...  I'll check out your "discoveries" when I have a little time Matt.  I'll also post mine if I can get this controller to align with my motor specs.


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## mattthemuppet2 (Aug 12, 2015)

those are pretty sweet drives by all accounts  Not sure how much I could add, I'm about at my limit with what I'm doing right now!


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## markba633csi (Aug 14, 2015)

Reven: I would stick with the KB setup because they are SCR output not Mosfet which while being older technology is probably more reliable for the long term.  Also keep in mind that many chinese treadmill motors are rated at higher horsepower than they actually are. Yours might actually be around 1.5-2.0 HP.  
By the way, what size horsepower (current sensing) resistor are you using now?  The only real limitations on the KB controllers are the SCR ratings, the heatsink size, and the horsepower resistor.  It sounds like you may be right in the sweet spot already- nothing more to do.  I'm using a KBIC 125 with a 1/2 horse servomotor on my 6" Atlas. I might have the manual for the KBMM here I could send you-let me know.
Mark S.


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## markba633csi (Aug 14, 2015)

Oh I see you've got the data sheet, you just couldn't link to it- never mind
MS


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## toolman49 (Aug 15, 2015)

G'Day Fellas,
Manuals are available for download from KB Electronics,  for the last 5 years I have been using a KBMM 225 on an auxiliary heat sink to run a Pacific Scientific 1.5 HP motor  (full size horses not Asian bonsai ones)  on my  12 x 36 lathe, works perfectly, provided you stick to the recommended 20:1 speed range ratio, push it beyond this and they start to get a bit cranky. Personally I think that adding variable speed drive to any machine tool is one greatest improvements in productivity you can make (along with a DRO of course).
Regards,
Martin


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## jere m (Aug 31, 2015)

Side note for those looking for controllers and motors (I am late to the conversation I guess) but a good source of full treadmills motor controller frame belt... Is Craigslist. I have bought one for $20 and picked up another for free. They are very common in the free section but not for long. Listing in the wanted section" treadmill $20" will garner some replies quickly. Paying $60 for just one part is a little steep in comparison so maybe this will help someone.


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## Chipper5783 (Nov 20, 2015)

Tread mill motor controller questions.  I must thank Reventropy for starting this thread.  I picked up a couple tread mill motors.  What are the various controller options?

The first one I sort of goof'd up as I did not grab the controller.

The second one, I also got the controller, but that does not clear it up much for me (where do I tie in a potentiometer?   On the treadmill, the cable goes up to the touch pad up top).  The board also drove a linear actuator (for the slope adjust).


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## mattthemuppet2 (Nov 20, 2015)

dang, those are a couple of beefy motors, especially the one with the 2 fans! I don't recognise the controller unfortunately, my guess for the pot would be the small plug with 3 wires coming out. Usually the white wire is the center wiper of the pot, but that might not translate to that style. Hopefully someone more knowledgeable will chime in!


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## Rickyoneshoe (Mar 10, 2016)

I believe the little plug with blk / red and wht is what your after. Do you have the rest of the machine to follow it up to the control panel?


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## kamn (Mar 15, 2016)

Chipper5783 said:


> Tread mill motor controller questions.  I must thank Reventropy for starting this thread.  I picked up a couple tread mill motors.  What are the various controller options?
> 
> The first one I sort of goof'd up as I did not grab the controller.
> 
> ...



Give me until the afternoon and I can get the schematic off the machine because I have the same setup as your second motor and controller and I took a pic of the schematic before I tossed the rest of the machine.
And for your first motor, just get an MC60 controller off of ebay or another treadmill that has a pooched motor


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## kamn (Mar 15, 2016)

here is the schematic to that motor and controller




And this as you can see is that same as yours but I haven't had a chance to wire in a potentiometer



Im not sure that this controller could work due to the fact that where you would add a potentiometer is a phone jack style plug.......would need to figure out which wires controlled the motor speed. The section that controlled the linear jack for slope adjustment on the treadmill is ignored all together


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## CNC tech room (Jul 31, 2017)

I have the same motor and have tested it with a Minarik speed controller, and it works fine. Check them on Ebay for cost


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