Another Treadmill Motor Speed Controller conversion thread

[Inferno]

This could be the way to go.
I think I have 100 555 timers laying around.
It seems this could also work with the Arduino I mentioned above.

I can take the schematic from the youtube video and build the circuit board (3 of them) for under $20
I could get 500 made for about a buck each.

The Smithy comes with a pair of switches. ON/OFF and FWD/REV
A pair of DPDT switches with the youtube circuit should work perfectly.

 

[RJSakowski]

I found this and wonder what



I found this one, how does this look? Not sure if this would work and if I read it right but looks like it works up to 2000 watts @ 90v with 110v AC input for $65 to your door.

https://www.ebay.com/itm/AC20-110V-input-DC-Motor-Speed-Controller-Board-PWM-Spindle-2000w-w-PLC-MACH3/114019185482?_trkparms=aid=555021&algo=PL.SIMRVI&ao=1&asc=20190711100440&meid=e7b187fcccdf4e10b6267352668b29d9&pid=100752&rk=17&rkt=18&mehot=co&sd=192669869665&itm=114019185482&pmt=1&noa=0&pg=2047675&algv=SimplRVIAMLv5WebWithPLRVIOnTopCombiner&_trksid=p2047675.c100752.m1982&autorefresh=true



EDIT: I also found the same one on Aliexpress for $44 to front door, via slow boat from Asia.

https://www.aliexpress.com/item/329...earchweb0_0,searchweb201602_,searchweb201603_

I had looked at that one previously. What bothered me about it was the 110 volt a.c max warning. My mains voltage can go as high as 130 volts at times. Also, my motor is a 130 volt motor so I would be derating it by 50% if I were running on 90 volts out. Aside from that, it looks promising.

 

[RJSakowski]

Am I reading it right that you'd have to use the speed control instead of an on-off switch?

As I read it, the caution pertains to instant reversing of the motor. There would be a very high current surge in flipping from forward to reverse before slowing or stopping the motor.

 

[RJSakowski]

This could be the way to go.
I think I have 100 555 timers laying around.
It seems this could also work with the Arduino I mentioned above.

I can take the schematic from the youtube video and build the circuit board (3 of them) for under $20
I could get 500 made for about a buck each.

The Smithy comes with a pair of switches. ON/OFF and FWD/REV
A pair of DPDT switches with the youtube circuit should work perfectly.

What "this" are you referring to?

 

[Inferno]

What "this" are you referring to?

My YouTube links disappeared. I'll see if I can post them this evening.

 

[silverchips]

I had looked at that one previously. What bothered me about it was the 110 volt a.c max warning. My mains voltage can go as high as 130 volts at times. Also, my motor is a 130 volt motor so I would be derating it by 50% if I were running on 90 volts out. Aside from that, it looks promising.

Thank you RJSakowsk for looking at it and letting us know.

I also saw that note not to exceed 110v which would be a concern but was wondering how realistic that is considering that would not make it very usable on any public electrical system supplying 110-120v? I also see no adjustable pots for slow start, torque and for anything else?

In regards to 90V, don't most treadmill motor companies boost the spec numbers (voltage & rpm) in order to advertise higher HP but realistically the motors work in constant in 90V and lower?
Also, wouldn't a DC treadmill motor deliver high torque at lower speed speeds with a PWM DC controller that has a constant torque operation feature on it giving it the rated torque at the rated armature current independent of speed allowing a constant torque capacity regardless of speed?
With that you wouldn't be losing a lot of power/derating it? I'm asking this because I wouldn't think any of us (hobby-machinist) would use a treadmill motor at full speed at its high rpms (4500....etc) unless you're trying to use it for a sensitive drill press or similar but a treadmill motor is way overkill for that? I'm at the reality that I would never see an actual 2+ horsepower out of a treadmill motor and just hoping for around 3/4-1hp with torque in a typical hobby machinist scenario?

Sorry for all the questions, I wish I was able to add more value to this thread but I'm still learning and very much appreciate to ones who have been answering questions and giving out good info. I do think if finding a cheap solution to Inferno's orig post will be very beneficial to many of us here on Hobby-Machinist and hopefully for Inferno.
If we can find a cheap, quick & viable solution to using a treadmill motors in our shops would be very useful. Cheers

 

[wa5cab]

I haven't gone and looked at the actual specifications but the "do not exceed 110 V" may be referring to the DC output voltage, not the AC input.

 

[RJSakowski]

I haven't gone and looked at the actual specifications but the "do not exceed 110 V" may be referring to the DC output voltage, not the AC input.

The controller can be operated on either a.c. or d.c. input. The label clearly states AC: 15 - 110 V. DC: +20 - 150 V. I interpret the 2 kw rating @ 90 volts to mean the maximum output voltage is 90 which, for a given current, would give the highest power rating.

My concern is that the bridge rectifier and/or the filter capacitors are the limiting factor. To operate safely on 120 volts, the rectifier and capacitors should have a minimum rating of 200 volts.

Thank you RJSakowsk for looking at it and letting us know.

I also saw that note not to exceed 110v which would be a concern but was wondering how realistic that is considering that would not make it very usable on any public electrical system supplying 110-120v? I also see no adjustable pots for slow start, torque and for anything else?

In regards to 90V, don't most treadmill motor companies boost the spec numbers (voltage & rpm) in order to advertise higher HP but realistically the motors work in constant in 90V and lower?
Also, wouldn't a DC treadmill motor deliver high torque at lower speed speeds with a PWM DC controller that has a constant torque operation feature on it giving it the rated torque at the rated armature current independent of speed allowing a constant torque capacity regardless of speed?
With that you wouldn't be losing a lot of power/derating it? I'm asking this because I wouldn't think any of us (hobby-machinist) would use a treadmill motor at full speed at its high rpms (4500....etc) unless you're trying to use it for a sensitive drill press or similar but a treadmill motor is way overkill for that? I'm at the reality that I would never see an actual 2+ horsepower out of a treadmill motor and just hoping for around 3/4-1hp with torque in a typical hobby machinist scenario?

Sorry for all the questions, I wish I was able to add more value to this thread but I'm still learning and very much appreciate to ones who have been answering questions and giving out good info. I do think if finding a cheap solution to Inferno's orig post will be very beneficial to many of us here on Hobby-Machinist and hopefully for Inferno.
If we can find a cheap, quick & viable solution to using a treadmill motors in our shops would be very useful. Cheers

As to torque, current is an often used surrogate for torque. In that regard, a PWM controller stands out because pulses of full voltage and therefore full current are delivered to the motor.

My setup will use the highest ratio pulleys on the low speed setup which will give me about 1200 rpm at the spindle for 4090 rpm motor rpm. This will hopefully give me the spindle range to cover 95% of operation without the need to change the belts. Keep in mind that hp is the product of motor speed and torque. A 2.5 hp motor @ 4090 rpm and with a fairly constant torque curve will only be putting out 1 hp @ 1725 rpm. Less yet at lower speeds. Here are the calculations that I made for my selected motor as compare to those for the OEM motor.

 

[silverchips]

I haven't gone and looked at the actual specifications but the "do not exceed 110 V" may be referring to the DC output voltage, not the AC input.

Sadly I just looked at the specs again and the answer is no to United States.
Here is what the specs quote:

“We convert 220V/380V to 110V with a transformer.
2) In some countries, the voltage is 115V, 120V or 127V which will damage the driver. For example, this driver can connect to mains power in Japan directly, but not United States.
3) A transformer is suggested to use and convert mains power into less than 110V to power the driver.”

 

[AGCB97]

“We convert 220V/380V to 110V with a transformer.
2) In some countries, the voltage is 115V, 120V or 127V which will damage the driver. For example, this driver can connect to mains power in Japan directly, but not United States.
3) A transformer is suggested to use and convert mains power into less than 110V to power the driver.”

Where do you see that statement? I looked 3 times and can't spot it.
Thanks
Aaron