Hello all, like many others I'm new here, any help with my problem will surely be appreciated. I recently purchased a scr 10000W motor controller from ebay that I want to use on a treadmill motor. I watched several video's on youtube and I have it set up but the pot is 500k which I believe is too much for my set up. I can't get low speeds that I need for my application. The pot will not start the motor until it is better than half way through it's travel and when it does start it's way to fast , when I try to lower the speed it stops.

My first question is, can I do something to get slower speeds by possibly changing the pot to a lower value or by modifying this set up in such a way that will provide lower speeds ? I do not need anything higher than 200rpm's. I only need 10 minuit intervals of use every 1/2 hour.

The next question may solve my problem but I am uncertain how to go about setting it up. I have the motor control board from the treadmill. I understand where the ac power comes in and the DC power comes out, but I can find no where on the board to connect a pot for speed control. I'll include a picture. Maybe one of you experts can look over the picture and advise me how to proceed if it's at all possible. It runs with the scr set up but I believe the PWM motor controller will do a better job if I can get it working. If it is possible to connect a pot, what size would I need. The board is # B017D

Thank you in advance for any advise you can provide.

 

Too bad you did not pick up one of the MC2100 or MC-60's, they are more popular and there is a lot of info out there on them.
They uses the same aluminum H.S. frame
What is the notation on the small 4 pin plug at the lower end of the pic?
It appears to be a PWM controller and perhaps uses a PWM command signal as the MC2100 does?

 

Too bad you did not pick up one of the MC2100 or MC-60's, they are more popular and there is a lot of info out there on them.
They uses the same aluminum H.S. frame
What is the notation on the small 4 pin plug at the lower end of the pic?
It appears to be a PWM controller and perhaps uses a PWM command signal as the MC2100 does?

I'll do my best to explain, there are only 4 possible connectors on the PWM board. There is no other place on the board to make a connection of any kind. (1) To the extreme right slightly down from the long black componet is a 2 pin connector marked "spd"
(2) Directly in front of the same componet is a 4 pin female marked "female". (3) Further down from the same long black item, near the lower edge is a 5 pin connector, it's marked from left to right- sw-+12v-txd-rxd-Gnd and directly right of that connector is a 3 pin connector (4) nc vr. Hope this helps, if not I'll have to go another route. I was hoping there was a way to use the PMW, I can always use the scr on another project. Thank you for taking the time to help me with this problem. I will go which ever route you guys recommend, your help is very much appreciated.

 

If you feel it does operate with a POT, the typical values are 5K linear, with 10K tops.
Is the pot a logarithmic type?

 

If you feel it does operate with a POT, the typical values are 5K linear, with 10K tops.
Is the pot a logarithmic type?

I does in fact operate with the pot that came with the scr, however, the value of that pot is 500k. It is not giving me the range I need for my project, it's much too fast at startup. If you think a 5K pot will work I can get one from our local electrical supply store and give it a try. I may have to get one of the alternative boards you recommended if the lower value pot does not work.
Thanks again for the reply. Mechanical I can easily handle most anything that comes down the line, but electrical is a different animal. I thought this was going to be easy. HaHa shame on me.

 

I does in fact operate with the pot that came with the scr, however, the value of that pot is 500k. It is not giving me the range I need for my project, it's much too fast at startup. If you think a 5K pot will work I can get one from our local electrical supply store and give it a try. I may have to get one of the alternative boards you recommended if the lower value pot does not work.
Thanks again for the reply. Mechanical I can easily handle most anything that comes down the line, but electrical is a different animal. I thought this was going to be easy. HaHa shame on me.

PS I think it's a linear pot that came with the scr.