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View Full Version : Treadmill motor wiring help needed please.



Rob Garner
10-18-2011, 02:49 AM
Gentlemen,

I'll cut right to the chase, I am not very electronics savy, given the info provided, is it possible to add a rotary pot to control the motor speed?

The plan is to fit the motor to a squirrel cage blower for a fume/exhaust hood over my welding table.

Google is not turning up much info. The treadmill is a Weslo Cadence 55. It uses an mc-1000 SCR motor controller. The control console is digital and uses membrane switches which is where the problem lies.

http://i159.photobucket.com/albums/t150/robg_010/treadmill/treadmillwiringdiagramMedium.jpg

http://i159.photobucket.com/albums/t150/robg_010/treadmill/treadmillwiringdiagrambackMedium.jpg

http://i159.photobucket.com/albums/t150/robg_010/treadmill/S6304277Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/treadmill/S6304262Medium.jpg

continued next post.

Rob Garner
10-18-2011, 02:50 AM
http://i159.photobucket.com/albums/t150/robg_010/treadmill/S6304254Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/treadmill/S6304267Medium.jpg

If it comes down to it, I will trim the console down to the bare minimum and mount it some way.

Bmyers
10-18-2011, 06:59 AM
short answer: NO

long answer:

http://bbs.homeshopmachinist.net/showthread.php?t=49952&highlight=treadmill+motor

EVguru
10-18-2011, 08:18 AM
short answer: NO

long answer:

http://bbs.homeshopmachinist.net/showthread.php?t=49952&highlight=treadmill+motor

Short answer: Maybe!

The motor controllers being discussed in the link are MOSFET types (MC 2100), which would be PWM controlled. The motor controller in the diagram above is an SCR controller, which would typically be voltage controlled. Although it recieves a PWM signal, it may well integrate that signal on-board to derive a DC voltage, so a pot could be substituted to provide that voltage. Your speed control would be open loop though.

jnissen
10-18-2011, 09:27 AM
What is the symptom on the controller board? From the look of it the snap switches look like they are probably worn out or acting up. Why not remove the control panel and replace the switches/buttons? The IC on the board is likely a small microcontroller that scans and de-bounces the buttons and runs the LCD. The transistors are likely for signal amplification back down to the SCR board or for level converting from one voltage domain to another higher domain. The diodes and protection circuit on the upper right appear to be for power supply regulation up on the control card. Verify voltages at the IC's and if OK then concentrate on the mechanical switches. Likely shorted out. A hour with a scope and a multimeter would get you far.

BTW - Check to see what part number is on the 14 pin IC shown on the controller. If it's a microcontroller then it likely has custom code for this unit programmed into it. Different cadences, workout scenarios, etc... Worst case looks like the controller is available for a bit over $100.

.ps Remove Protective Film Before Use!

MaxHeadRoom
10-18-2011, 10:37 AM
There have been quite a few different posts in this forum and CNCzone etc, on this subject for the T.M. PWM control, one of the simplest solutions is to make up a small PWM circuit from something like a 555 timer and use a linear pot for speed control.
There should be quite a few circuits that could be used out on the web.
Max.

Rob Garner
10-18-2011, 05:54 PM
Thank you for the responses.

It's odd that the first link posted did not turn up in any of my searches while all of the others did. I should have been more clear in the first post.

Thanks for your help. I will post the project when I decide which avenue to take.

topct
10-18-2011, 06:50 PM
I think everything is on the motor board to make the motor run. Eliminate the console. You can unplug it from the motor board. Wire a 5K pot with the center tap connected to the blue (PWM) wire, and from either outside tap from the pot to the black/white ground wire.

If that works to make the motor run, you can switch the ground wire to the other tap on the pot to change the rotational direction of the pot. You could also put a switch on the center tap of the pot that will stop the motor and when switched back on will bring the motor up to the speed that the pot was set at.

Give the controller a tiny bit of time to run the motor up to speed, they have a soft start feature built in.

I suspect the read switch to be a safety tether and it could just be shorted.

MaxHeadRoom
10-18-2011, 07:57 PM
I think everything is on the motor board to make the motor run. Eliminate the console. You can unplug it from the motor board. Wire a 5K pot with the center tap connected to the blue (PWM) wire, and from either outside tap from the pot to the black/white ground wire.



The only thing wrong I can see with that is that is a simple analogue signal, the drive expects a PWM signal?
Max.

topct
10-18-2011, 08:14 PM
The speed of the pulse is controlled with an analog voltage.

MaxHeadRoom
10-18-2011, 08:55 PM
Note the Note:
Digital multimeters may have difficulty measuring this (PWM) signal and may only show a maximum of 1.5vdc!!
Max.

jakep_82
11-03-2015, 05:19 PM
Short answer: Maybe!

The motor controllers being discussed in the link are MOSFET types (MC 2100), which would be PWM controlled. The motor controller in the diagram above is an SCR controller, which would typically be voltage controlled. Although it recieves a PWM signal, it may well integrate that signal on-board to derive a DC voltage, so a pot could be substituted to provide that voltage. Your speed control would be open loop though.

Short answer: Yes!

I know this is an old post, but I wanted to add some information for people like me. I recently picked up a similar treadmill that uses the same motor controller (MC-1000). The motor controller doesn't seem to care whether the signal it receives is PWM, or just straight DC. I simply connected a 5K potentiometer to the red, black, and blue leads (blue in the center) coming out of the board, and I'm now able to control my speed. The only issue is the controller will shut the motor off if it receives more than about 11V (the controller outputs 12V). To solve this problem I wired a 1K trimpot as a variable resistor between the red wire and the potentiometer. This allowed me to adjust the maximum voltage so I can use the full range of the potentiometer. I also added a switch between the potentiometer and the controller on the blue signal wire. When the controller is turned on, it requires 0V on the signal line before it will turn the motor on. The switch allows me to turn the motor off and on at the same setting without the need to zero the potentiometer.

mattthemuppet
11-03-2015, 05:25 PM
I also added a switch between the potentiometer and the controller on the blue signal wire. When the controller is turned on, it requires 0V on the signal line before it will turn the motor on. The switch allows me to turn the motor off and on at the same setting without the need to zero the potentiometer.

you can also cut a resistor that's wired to the wiper wire post (the center wire from the pot) which will do the same thing

Paul Alciatore
11-03-2015, 07:25 PM
I would have suggested a similar thing. The PWM is just the way a microprocessor generates a DC signal. There is probably a capacitor in the actual motor controller that filters that PWM signal into a DC level that actually controls the motor's speed. So a pot would work just fine.

"It will all be better when it goes digital." Oops, we are already there!.

pablo
08-03-2018, 04:59 PM
Good afternoon, I saw that a few years ago they were talking about mc-1000, I'm from Argentina and I want to repair it for my tape, the disloyal technicians charge me more expensive than the new one, I'm missing the 5 transistors that are connected to the heat sink, ( Q4, Q7, D16, D13 and D17), and I do not know their values, can any of you pass them to me? THANK YOU VERY MUCH!!!!

pablo
08-03-2018, 05:01 PM
Good afternoon, I saw that a few years ago they were talking about mc-1000, I'm from Argentina and I want to repair it for my tape, the disloyal technicians charge me more expensive than the new one, I'm missing the 5 transistors that are connected to the heat sink, ( Q4, Q7, D16, D13 and D17), and I do not know their values, can any of you pass them to me? THANK YOU VERY MUCH!!!!

PStechPaul
08-03-2018, 06:31 PM
Q4 and Q7 would be transistors, probably MOSFETs. You can probably replace them with almost any device with equal or higher voltage and current. D13, D16, and D17 are probably center tapped diodes - again, replace with a higher rated part. They might also be SCRs. Can you take a couple close-up photos of the board?

The following may also help:

https://el34world.com/Misc/Cnc/TreadmillMotor1.htm

https://el34world.com/Misc/Cnc/Files/Terrys_Dual_555_MC_2100_Driver_Circuit.pdf

https://sonsofinvention.wordpress.com/2012/11/12/mc2100-pwm-controller-schematic/

https://www.vfds.com/manuals/ac-tech-mc1000-manual.pdf

https://forum.allaboutcircuits.com/threads/understanding-the-mc-60-treadmill-motor-controller-schematic.77083/

https://www.instructables.com/id/Use-a-Treadmill-DC-Drive-Motor-and-PWM-Speed-Contr/

https://www.amazon.com/Treadmill-Doctor-MC-1000-Motor-Control/dp/B006E802X2

https://www.treadmillpartszone.com/treadmill-controller-part-mc1000-248574/

J Tiers
08-04-2018, 12:58 AM
What Paul Compton (evguru) said.... the signal from the control is converted to make a DC signal, so you can do that with a potentiometer.

The "pot" will, however, be "hot" with the incoming AC power voltage, so it will need to be insulated and isolated for safety. One with a plastic shaft is ideal.

MaxHeadRoom
08-04-2018, 10:17 AM
Good afternoon, I saw that a few years ago they were talking about mc-1000, I'm from Argentina and I want to repair it for my tape, the disloyal technicians charge me more expensive than the new one, I'm missing the 5 transistors that are connected to the heat sink, ( Q4, Q7, D16, D13 and D17), and I do not know their values, can any of you pass them to me? THANK YOU VERY MUCH!!!!

IIRC you will find the MC1000 is an enhanced version of the MC-60 which has the typical 2 SCR's and 3 power diodes, they can all be had from Littlefuse Digikey etc.

The 5 should have the number on them, If you need the values or equiv. I can look them up as I have replaced these in the past.
Max.

MaxHeadRoom
08-04-2018, 10:48 AM
The Littlefuse S8020L SCR and DUR301220 rectifier.

BTW this is a Lenze VFD.;)





https://www.vfds.com/manuals/ac-tech-mc1000-manual.pdf

Max.

mickkell
08-05-2018, 08:23 PM
Have you seen this Video? Seems easy enough. https://www.youtube.com/watch?v=_NmAFZMAfH8&t=303s