Another Treadmill Motor Speed Controller conversion thread

[RJSakowski]

My motor has an external press on fan and I will go with that initially. There is concern about insufficient cooling at low rpm for motors with built in fans and one solution is to use an external high volume computer fan for cooling.

Banggood has something like 250 different motor controller on their site but none that I saw that meet the requirements of 120 v.a.c. input and 15 amps out. It woulden't ake much to modify one though. You would need to add the full wave bridge, the filter capacitor, and a suitable MOSFET transistor to be able to use with a higher hp motor.

From what I have read, the undesirable soft start feature of the OEM treadmill controllers can be defeated by simply snipping one resistor.

 

[Z2V]

I’m afraid I don’t have much to offer in answers to your questions. I’m using treadmill motors on a belt grinder, a horizontal band saw and a buffer/ polishing stand. I’ve used the original pulley and flat belt on all three machines. I have also used the treadmill control board on them as well. MC60 on the saw and buffer and MC2100 on the belt grinder.
I have seen others use the KB control successfully but as you mentioned they are pricey.l
On the mill I used a three phase motor and a VFD.

 

[Z2V]

From what I have read, the undesirable soft start feature of the OEM treadmill controllers can be defeated by simply snipping one resistor.

I‘ve read this as well but have not had an issue with the soft start because one speed does not fit all applications. It’s just turning a knob. That’s my thinking

 

[silverchips]

My motor has an external press on fan and I will go with that initially. There is concern about insufficient cooling at low rpm for motors with built in fans and one solution is to use an external high volume computer fan for cooling.

Banggood has something like 250 different motor controller on their site but none that I saw that meet the requirements of 120 v.a.c. input and 15 amps out. It woulden't ake much to modify one though. You would need to add the full wave bridge, the filter capacitor, and a suitable MOSFET transistor to be able to use with a higher hp motor.

From what I have read, the undesirable soft start feature of the OEM treadmill controllers can be defeated by simply snipping one resistor.

I’m afraid I don’t have much to offer in answers to your questions. I have also used the treadmill control board on them as well. MC60 on the saw and buffer and MC2100 on the belt grinder.
I have seen others use the KB control successfully but as you mentioned they are pricey.

Thank you to the both of you for the quick replies. I hope I'm not hijacking the OP thread and hope these questions also help him and others in the same boat.

DC speed controllers for the size motors we want to use (approx 130v @approx. 2.5hp/1500w/12amp) fall into a conundrum. Finding a cheap but good one is proving difficult. While as described above by earlier post's they're fairly easy/cheap to cobble up a self-made speed controller for the ones who are adept to it (I am not) however finding a cheap one online, even overseas is so far proving hard to find in wanted size. Looking on Banggood, they don't seem to really offer speed controllers for the needed wattage/V. and when they do the prices match a US made KB or similar. I found more possibilities on Aliexpress but still did not find anything that can handle above 1000 watts @90v. A 1500-1800 watts/12+amp is what is needed/preferrable.
So far it looks like finding a used KB or similar used ready to go is the most reasonable economically (if found cheap) if you're not building/cobbling your own. The prices sellers are commanding & silly on eBay for used DC controllers from treadmills are not that much less than a used KB and you'll still need to spend time and material for an enclosure to finish them.

Any leads or direction towards a good & inexpensive DC speed controller would be greatly appreciated. I don't mind building an enclosure.

Also, I found replaceable motor fans on Aliexpress for $10-$15 but in bigger and small hole size than what I need, there are some on amazon & eBay as well for a slightly more. I decided to use mine off the fly wheel (pulled off) and will make a bushing to adapt it to my .63" shaft.

Looking forward to reading more posts and advice

 

[Inferno]

The motor I'm using does have the external fan. I removed the fan while working on it and to clean out the fibrous dust that had accumulated under it.

I'm interested in the ground-up spare parts PWM build.
Though I couldn't build one myself, I'm familiar enough with electronics that I can follow a circuit build. Heck, I can even design a circuit board for a schematic if needed. I do it pretty often. If someone wants to go that route, I even have circuit boards made from time to time. In bulk they are pretty cheap.

I probably won't work on this much during the week. I mainly recover from workdays this time of year. I spend most of Saturday recovering as well. I will do a lot of thinking about it as I drift off to sleep. It's amazing how that helps sometimes.

I also just realized that the SCR will work perfectly for a different project I'm working on. It's almost too simple to even talk about but it's an array of muffin fans put together to create a slight negative pressure field inside a 100 year old machine.

 

[Inferno]

Also, I found replaceable motor fans on Aliexpress for $10-$15 but in bigger and small hole size than what I need, they're some on amazon & eBay as well for a slightly more. I decided to use mine off the fly wheel (pulled off) and will make a bushing to adapt it to my .63" shaft.

Looking forward to reading more posts and advice

You can always get a smaller fan bore than you need and open it up a little on your drill press. Drill bits tend to like to follow pilot holes.

 

[silverchips]

You can always get a smaller fan bore than you need and open it up a little on your drill press. Drill bits tend to like to follow pilot holes.

Thanks Inferno,

Yes you are correct, but figured if I have to spend time and money altering a fan I have to purchase, I might as well first try to alter and use the one I already have (if possible). Thats the cheap bastard in me talking.

At least its good to know that these fans for treadmill motors are easily available and using a small biscuit fan on the bottom as an option and a good idea.

 

[RJSakowski]

I finished laying out my circuit board for the VSD in SolidWorks this morning and imported it into SprutCAM. The toolpaths have been calculated and G-code posted. 4700 lines of G code! It will take about a 1/2 hr to run the program. From there it is a short step to populating the board and firing up the circuit.

I have only laid out the control portion. I purposly separated the the power supply and switching MOSFET transistor from the control board., More later.

 

[silverchips]

I finished laying out my circuit board for the VSD in SolidWorks this morning and imported it into SprutCAM. The toolpaths have been calculated and G-code posted. 4700 lines of G code! It will take about a 1/2 hr to run the program. From there it is a short step to populating the board and firing up the circuit.

I have only laid out the control portion. I purposly separated the the power supply and switching MOSFET transistor from the control board., More later.

Reading this, I solidly stand in my defense of trying to find a finished (cheap) one.

Don't get me wrong, this is awesome, very useful and thoroughly impressed and we definitely need more of this in the world but for me to learn how to do that would be equivalent to learning how to speak Swahili. As I get older, I'm getting better on learning to pick my battles.

Also sounds like your taking the same design cues and signal control of a high end audiophile amp. Looking forward to seeing it complete.

 

[Inferno]

Reading this, I solidly stand in my defense of trying to find a finished (cheap) one.

Don't get me wrong, this is awesome, very useful and thoroughly impressed and we definitely need more of this in the world but for me to learn how to do that would be equivalent to learning how to speak Swahili. As I get older, I'm getting better on learning to pick my battles.

Also sounds like your taking the same design cues and signal control of a high end audiophile amp. Looking forward to seeing it complete.

FWIW, my neighbor only speaks Swahili. Nope, not kidding.

I don't think she'd understand the electronics either.