[TroyO]

I'm looking for a basic DC motor controller for a treadmill motor.

Motor:
1.5 HP, 90V 18A

I heard that SurplusCenter used to have some for around $50... any similar deals still out there?

My understanding is that 1 HP versions will work for the 1.5 HP motor... I just won't get full power. Since it's a 9x14 benchtop lathe that shouldn't be a problem, I think. Anyone know if using a 1 HP controller on a 1.5 HP motor would cause any problems?

I had the one that was in the treadmill I scavanged.... but through a comedy of errors I ended up shorting out the control lead. It was only a 5V lead.. but it sparked pretty good and now no 5V. :-(

Actually... it was kind of funny. I was showing my wife how I had figured out the wiring to use the controller to run the treadmill and my dog. (who hides under the bed when there are flies around....) decides to run over and jump on the treadmill. (How he all the sudden got guts I'm not real sure...)

The result was as expected... poochie gets launched and I of course cut the speed off and go to check on the dog. The dog wasn't hurt, but when I picked the POT back up it shorted and poof... my variable speed dreams go up in smoke, LOL.

Anyway... I still got the motor so I got something of value from the thing but I am major bummed that it looks like I made a $150 slip of the hand.

[jduke]

I would like to know this as well, since craigslist seems to always have a few treadmills

duke

[TroyO]

Yeah, gutting another treadmill is an option... but I don't have a truck so getting those things home isn't that easy for me.

There's tons of free/cheap treadmills out there, and they usually do have a motor controller capable of running whatever motor they have in them.

If you don't smoke the controller in the process, anyway. :-(

[Al_The_Man]

You just have to search ebay for KB or Baldor DC SCR drives.
Al.

[jduke]

Yeah, gutting another treadmill is an option... but I don't have a truck so getting those things home isn't that easy for me.

There's tons of free/cheap treadmills out there, and they usually do have a motor controller capable of running whatever motor they have in them.

If you don't smoke the controller in the process, anyway. :-(

I did the same thing with the first treadmill that I scavenged for parts, and lost the motor about 3 moves ago.

I was able to pick up a treadmill for $20 not long ago, that has a rheostat for the motor speed.

I noticed that it has some sort of load compensation as well. Initially I thought there was a short somewhere, because when the motor gets up to speed, if it doesn't have a load, it will sound like its cutting out, then back on when some load is applied.
Is that typical for treadmill motors and controllers?

Duke

[Al_The_Man]

Many current treadmills do not have a potentiometer and speed is digitally entered and controlled by a MicroChip.
The other is that there are different motor types and quality's used, some are Universal motor and some are DC.
They can also have a feedback device of some kind, and also have a compulsory slow start feature, where at power up, the pot or control has to initially be at zero before the motor can be controlled.
If the motor starts and backs off, especially with no load on it, my guess would be the controller has a primitive speed control on it, on most treadmills, there is some kind of load at all times.
Al.

[TroyO]

What a difference a day makes... or maybe a better idea of what search terms to use! I guess I was just too impatient with Ebay.. didn't seem like there was squat yesterday.

I just scored a KBMM225 (D?) for $45 including shipping off Ebay. It might only work on 220V, I'm not real sure if the "3835D" after the part number means it's the dual voltage (115 or 220V) model or not. I have 220V in my shop anyway, so no big deal either way. (Actually, running at 220V I can get the full 1.5 HP without buying the big heatsink)

It's rated for 1.5 HP so I should get the full output of my motor as well.

http://cgi.ebay.com/DC-Motor-Speed-C...d=p3286.c0.m14

There's 9 left... thought others might want to know.

[TroyO]

Many current treadmills do not have a potentiometer and speed is digitally entered and controlled by a MicroChip.

The control scheme on the one I blew was a mix of the two... the digital control panel put out a PWM signal that supplied 0-5V to the motor control board. By replacing that with a potentiometer you could control the board manually as well.

The connection was listed in the schematic as (Black-0V) (Red+5V) and (White 0 to 5V)

On the white, 0V was off and 5V was full speed. Actually, the Black/Red was slightly out and was about 5.5V... not too big a deal, but the controller cut off power to the motor if there was anything over +5V to the white... so you would speed up until the potentiometer was past about 90% of full then turn off.

It would have been easily fixed with either some regular resistors or a trim pot to dial the voltage to exactly 5V when the knob was cranked all the way up. Of course, it was kind of moot in my case since I horked the controller but maybe someone else will find the info useful.

[Al_The_Man]

I believe the D stands for dual voltage output, either 180 or 90v motor, but still 240v input.
You will need the correct plug in series resistor if it comes with the wrong value, you can get them at Baldor or KB motor suppliers.
I would still tend to fit a heat sink of some kind, regardless as it avoids blowing the SCR's, just a chuck of aluminum 1/4" or 1/2".
IIRC these are 2 quadrant drives, if so and you need reversing, it will need to be done externally.
Al.
I just checked the ebay link and they show fitted with heat sink.

[TroyO]

I found the data sheet at the KB website..
http://www.kbelectronics.com/data_sheets/kbmm.pdf

KBMM-125 115VAC In only
0-90VDC out (1.5 HP)

KBMM-225 230VAC In only
0-180VDC@230VAC (3HP),
0-90VDC@230VAC* (1.5 HP)

KBMM-225D 115VAC or 230VAC In
0-90VDC@115VAC (1.5HP),
0-180VDC@230VAC (3HP),
0-90VDC@230VAC* (1.5 HP)

*Step down operation, may reduce brush life
** I listed the "With heatsink option".. without heatsink the HP output is 1/2.

So, it looks like if it is the D model it will take either input voltage and ouput either 90/180 VDC as well.

The 90VDC@230VAC ouput comes at the expense or running in "step down mode" which shortens brush life..... how much shorter it doesn't say.

Best bet would be to run it @ 115V if it's the D model. If not, I'll be stuck with 230V and using "Step down mode" but I can't imagine it's a huge percentage off of brush life anyway.

The Ebay ad lists the (3585D) number but I'm sot sure what that indicates... if it means it's a D model or not. The KB site doesn't list 3585D in any form. When I get it in hand it should be easy to figure out, I'll post what I find.

I think the heatsink in the pic on the Ebay ad is the standard one... KB lists a 6" x7" aux heatsink... I think you need bothe for full power. (It it just me or does that seem hugemongous... especially in ADDITION to the regular heatsink?)

http://www.kbelectronics.com/kbsearc...popup_9861.htm

Anyway... 'tis all still good news. I can use it for exactly what I need no matter which model it is and the price was right.

[Al_The_Man]

The link you have shows the brochure, the pdf manual is here.
http://www.kbelectronics.com/manuals...smt_manual.pdf
Al.

[TroyO]

Welll.... errr.. crap!

The motor controller arrived. It's just a plain KMM-225. That wouldn't be a problem, except it's the older "through hole" version of the KMM-225. The only functional difference? No 90V motor support.

Grrrrrr... LOL.

Manual for the Through hole version.
http://www.kbelectronics.com/manuals...ole_manual.pdf

So... I guess it goes back up on Ebay, see if I can get anything back for it. Unless someone wants a 220VAC/180VDC motor controller for $40? :rainfro:

[trienski]

Hi All,
Sorry to jump in in the middle of the thread but I am brand spanking new here and can use your help with something.
I've rescued a partial Image 15.5s treadmill laying dead along the road with its motor and controller still intact. I am thinking about marry the rescued parts with the existing drill press to make a variable speed shop drill out of the combo.
Has anyone have any information on the header HD2 on the controller board of the above treadmill? The information on the controller board is: "MC-2100SDI Rev. A". The header HD2 is a 8 pins header and I would like to find out the pinouts for the header so I can start tinkering with the controller to determine whether or not it is ALIVe. Appreciate your help.

Trienski

[Al_The_Man]

Hi All,
Sorry to jump in in the middle of the thread
Trienski

Looks like it petered out last July so I don't think that will be a problem!

You will be really lucky to find someone who did this with the same unit.
If you have everything there intact, it should not be difficult to reverse engineer it I would think?
Al.

[carl0s]

I have a question for you Al, on the subject of motors.
I know that many of the SCR controllers take 120vac in and give 90dc out, or 240 in and give 180dc out, which is great, because here in the UK my motor needs 180dc.

My question is on the motors. Do all the things that would have a 180v DC motor here in the UK have a 90v DC motor instead over there in the USA (e.g. Treadmills, Milling Machines, Lathes..) and if so, is it a totally different motor? Or can you run the 90v dc motors at 180v dc, just with half the current or something ?

[Al_The_Man]

I am not sure of your question, but here if you have a 90 v motor, you can actually run it on the 240vac version if you set the max speed pot accordingly, but I prefer to use the motor rated for the drive.
Most treadmill motors here are 90v, naturally, but there are DC servo motors that are rated around 200vdc that can be used on the 240v contoller.
Here in N.A. you have the option of 120vac or 240vac.
Al.

[2_many_hobbies]

Hey,

Figured I would jump in as I just setup a 1HP 90V DC motor myself. This Motor

I have had terrible luck with trying to find DC motors in Canada. Every treadmill I have seen has used a 1HP AC motor in an open frame and I luckily I stumbled upon Surplus Center as that motor above is a beast for $40

I was going to go with this controller from surplus center but it was $72 and I did not have the money.

I went to my local electronics store and got a terminal strip, heatsync, case, 50K potentiometer and an IRFP260N N-Channel Mosfet. Total came to $42 but you can go cheaper by not getting a nice case and switches or frying two of the $4 mosfets like I did. In the end though its a wonderful controller that after 45min on my lathe the motor casing is still cold and so is the mosfet. I am using a simple 555 timer to do PWM to the mosfet for speed control.

I'm going to take a video for youtube of the motor and controller tomorrow and upload a copy of the schematic to my site. Ill post it here too if your interested.

[lovebugjunkie]

I would be interested, please post the URL's when you have it up.
thanks
george

[Arich0908]

I just bought a KBMM125 great motor controller, I also Have a Min Mark. Any one wants it ant a decent price PM me is for 120v.Adjustable current from 0v to 90v

All the switches on your mill will work with the KB controller I know mine did.
And the Volts are fully adjustable , Ive used a 36v motor and 90v on my controller all I had to do was adjust current .
You cant go wrong with any of the major company's though.

[2_many_hobbies]

lovebugjunkie - I recommend you buy a ready made product off ebay or my previous link to surplus centers controller.

I have been using my motor for a week on 0.250" brass on my lathe and it works wonderfully. Today I had to face a 2" piece of steel and was turning at 150RPM and about 2min into it the mosfet EXPLODED! So yea.... I wont be needing to post a schematic as it did not work...

I am now in the midst of designing a SCR based phase controller with some more professional advice as apparently I suck. lol

Good luck!