hello, i have a 22vdc wheelchair motor with gearbox.

i simply need to control the motors speed with a pot. im not sure what type of controller or setup i would need for this. also this will run off 120vac instead of batteries. at 22v the motor runs really fast compared to what i need it to run at, I'm probably looking at a window of 0-12 or even 0-6 volts.

 

Why do you present it as a 22 volt motor? That is a very odd voltage. 6, 12, or 24 volts is much more standard. What kind of current does it draw? Do you have a transformer to step down the line voltage? If not, you will need to determine the correct voltage and current, and obtain one with those ratings. What is your application?

 

A quick google search finds
http://ourworld.compuserve.com/homepages/Bill_Bowden/page4.htm#ps3.gif

You will need more info to get the right controller, how many amps do you need?

Try to get a controller that has twice as many amps than you need so as to not overload it.

 

Because that's what the motor presented to me. Yes I know 22 is odd..
This is going to be used for a conveyor belt.
I do not have a transformer as I was hoping maybe I could have a 2 in 1 controller

I'm not sure on the amps myself I'm trying to get the info for the motor, all it has on it is company, model and 22v

 

i contacted cim but this is the only info that comes on the motor

cim
pm805-001
22vdc
040306

 

If it is anything like Permobill's C300 CORPUS, the motor is250W, 22V DC, @ 11.5A. Operates on two 12V batteries. To opperate from 120AC you need a brute-force power supply and a PWM speed control. For a power supply I used a dead UPS transformer, microwave filament transformer, a big bridge rectifier, 10A 120V fuse, & 20A DC circuit-breaker., +500μF cap. If you are despeaite, carefully remove high V winding from microwave oven transformer, also the filament winding. Wind on about 5 turns of any kind of wire, measure V and compute number of turns to give 24V AC. Remove wire , insulate primary with high temp, transformer tape, wind on required number of turns of # 10, magnet wire, or equivalent in a number of strands of lighter gauge wire. Might be around 55 turns as est. My suggestion-DO NOT DO IT. Maybe a 50A arc welder??

 

Here's a supply to look at:
http://www.mpja.com/prodinfo.asp?number=17429+PS
24VDC @ 12.5A POWER SUPPLY, $24.95 + shipping.

You'd be hard-pressed to find something that matched your requirements exactly at that price.

Add a PWM circuit for speed control.

 

pretty interesting, after calling a handful of people, i found out that the motor came off of a Permobill c300, nice call bernard! however i don't feel like making the project messy and doing something like you explained, I'd rather go sgtWookie's route.

24v for the conveyor is WAY to fast, i don't even want the motor to have 24v potential. like i said before im thinking 0-12 or even 0-6 volt rang.

with that said, im not sure where to start anymore, wouldn't i buy a transformer according to the controller's needs? and lets say a good guess at the motors amps is about 14 (the company said at 24vdc its about 20vdc)

so i guess i need to be looking for a 15 or so amp 12vdc PWM controller and a transformer that meets the controller's needs?

 

how about this for a controller?
http://www.electronickits.com/kit/complete/motor/CKMX066.htm

i can't find a 120vac to 12vdc 30amp power supply.. would i need the 30amp supply or could i go lower?

 

MY guess @ 12V current around 8A, should be easy to find & cheap.

 

Not so cheap, I'd stick with SgtWookie's power supply with PWM controller.

 

haha yeah i looked into some transformers, SgtWookie's link was a steal value.

however, i don't want to use 24v..

will this do?
http://www.mpja.com/prodinfo.asp?number=16013+PS

or could i still use
http://www.mpja.com/prodinfo.asp?number=17429+PS
and trim down the voltage some how?

 

I do not see a problem with 24V when used in conjunction with a speed controller, speed 0-max

 

well yeah, however the issue is safety. this is for a cooling conveyor belt that is in a bakery and the speed needs to be adjusted up a few notches every once in a while, the oven does not maintain a constant temp, 24v will mess the belt up physically and mechanically, its not designed to operate that fast. so i wanted 12v as the potential max, even though i think 12v is to much, i can work with that.

in the end i think it would be just fine to superglue some sort of stopper on the knob so it wont go any faster than i need...

i ordered this for the controller
http://www.electronickits.com/kit/complete/motor/CKMX066.htm

and this for the power supply
http://www.mpja.com/prodinfo.asp?number=17429+PS

now till they come in, thanks all i hope things work out, ill post back with some pictures.

cheers
seesoe

 

thank you everyone the system worked out great!, sorry for the late results
i bought a metal project box from radio shack and mounted the controller in there with a lighted power switch, i then cut a circle in the bottom of the box to align up with the circle on the top of the power supply, as the power supply had a cooling fan on it, i used its screws to screw the controller box to it. the motor is spring loaded for tension.

one thing im having issues with is the sensitivity, for my application the controller is very sensitive, besides gearing, would it be possible to change the 10k pot out for like a 20 or something? or it doesn't work like that?

thanks again

 

Thanks for the pictures. To decrease sensitivity of pot ajjustment, might add a resistor to each end of pot , or if 10k is required use smaller pot [ 2 to 3k]with resistors on each end to make total 10k with desired speed about in center of pot. Any chance for a schematic??

 

sorry about that i meant to link the controllers page and the PDF

 

Sorry. I missed PDF. The comparator ,IC/2,probably would not mind if you increased value of R5 & R6 a bit to decrease setting sensitivity, might try doubling.Would you let us know how it works out.

 

one of them is 4.6 kohm and the other is 5.6 kohm, would a 10kohm for both work?, or do i need to change the pot instead?

 

If your desired speed is around center of pot, 10k for each should be allright, keep 10k pot.[for now ].