Treadmill Motor Speed Controller

Thread Starter

Pollybell

Joined Aug 2, 2019
8
My DKN AirunX treadmill has developed the problem that there is insufficient voltage going from the circuit board to turn the motor. The motor runs fine when connected to a 12V rechargeable battery and all the other treadmill functions operate correctly. Finding a replacement circuit board has drawn a blank. I don't have the electronic knowledge to attempt a repair of the board.

I think it may be possible to power the motor directly from the mains and bypass the control board. Is this right and if so is there a ready made unit that I can simply connect to the mains and the 2 wires to the motor.

The motor is 2.25 Hp 180VDC 4800 RPM
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
You could get one of the other popular TM boards, MC-60 is a simple pot control with safety turn to zero first to start.
What is the number on the board or post photo.
Max.
 

Thread Starter

Pollybell

Joined Aug 2, 2019
8
Thanks for the response Attached are a couple of photos of the board - one showing the reference number on the mounting plate. Hope this is what you are looking for.

IMG_20190524_121008092.jpg

IMG_20190524_130213949.jpg
 
Last edited by a moderator:

MaxHeadRoom

Joined Jul 18, 2013
28,617
That is one I have not come across, the most common items that fail are the power carrying devices.
The relays are usually for the belt ramp/raise/lower etc.
Max.
 

jpanhalt

Joined Jan 18, 2008
11,087
A horsepower is 746 W. That controller is 400 W. You motor's nameplate rating is 2.25 HP (1.7 kW). It will not work, at least not for long.

Your original statement said, "The motor runs fine when connected to a 12V rechargeable battery ..."
Is that some sort of typo. It's a 180V motor.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
I have found testing the TM motors on a 12v auto battery detects many of the usual faults .
@Pollybell I suspect at that price, there is not many features on that drive, most likely Triac/rectifier based.
As I mentioned, you would be better off getting one with some features if still using it for T.M. purpose.
The MC-60 is about the cheapest/easiest to sub for T.M. use and features.
Max.
 

Thread Starter

Pollybell

Joined Aug 2, 2019
8
A horsepower is 746 W. That controller is 400 W. You motor's nameplate rating is 2.25 HP (1.7 kW). It will not work, at least not for long.

Your original statement said, "The motor runs fine when connected to a 12V rechargeable battery ..."
Is that some sort of typo. It's a 180V motor.
I tested it with a 12V rechargeable battery. It ran slowly and not under load. I just wanted to see if the motor was OK.
 

Thread Starter

Pollybell

Joined Aug 2, 2019
8
I have found testing the TM motors on a 12v auto battery detects many of the usual faults .
@Pollybell I suspect at that price, there is not many features on that drive, most likely Triac/rectifier based.
As I mentioned, you would be better off getting one with some features if still using it for T.M. purpose.
The MC-60 is about the cheapest/easiest to sub for T.M. use and features.
Max.
Thanks. Still want to use as a treadmill. Was hoping to find a ready made unit as my electronic knowledge is close to nil but will see if I can find a MC-60 unit.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
The MC-60 just requires power, 5k pot and the motor leads, although I am not sure if they come in a 230vac version, most I have come across are 120vac.
Using a cheap controller you are not going to get the level of control as a T.M. version, the next best would be one of the KB motor controllers that can be had in dual 120/240v.
Max.
 

Thread Starter

Pollybell

Joined Aug 2, 2019
8
Just thought I would report back and thank you all for your help. Ordered parts and wired it all up this morning and now the treadmill is back working.

I also found this video clip very helpful.

Thanks all.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
If that is what you used, keep in mind, you get what you pay for!
That is the very basic means of control and does not of course have any of the protection features for motor or personnel that a more sophisticated drive will.
Especially operating in a T.M. itself, It is possible to inadvertently apply a initial high voltage and overload the motor easily with a person on the belt particularly with a heavy flywheel on the motor.
Max.
 

Thread Starter

Pollybell

Joined Aug 2, 2019
8
I totally agree with your comments. I did try to source an MC-60, as recommended, but it looks like these are not available in the UK due to our electricity voltage. I am not sure what the UK equivalent would be to the MC-60.

I have managed to the get above configuration working but would still like something a little more robust.

I am still looking for a better setup but I am struggling to know what to get as my electronic knowledge is nil and google searching just gives me an overload of options and no clear insight as to what I should get. I only need it to power the treadmill motor with variable speed.

Inching forward hopefully.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
The other choices that cover 120v/240v are the DC motor controllers from KB, they can be obtained with the simple SCR bridge or PWM version.
Ebay usually has a few.
Max.
 
Top