CPE-2 motor fix - anyone tried it?

[hoffy]

Howdy,

I have finally gotten around to seeing what is wrong with my CPE-2. I took the motor out and connected it to a variable power supply and after a bit of coaxing, it seems to work fine. I then tried to connect it back into my jobo, but alas, it didn't spin.

I have found the following fix:

http://tech-diy.com/Photography/JOBO CPE2 Motor Speed Controller/jobo.htm

I am curious to see if anyone has actually tried this? If you have, have you been successful?

Cheers

 

[domaz]

It seems logical but you could accomplish the same thing without making your own PCB. Find a reversible Electronic Speed Control meant for an RC Car or Robot like this. Then connect the input voltage of the Speed Control to the 24VDC source on the Jobo (or to your own 24VDC source), connect the outputs to the motor and the control inputs to a microcontroller or RC transmitter that can control the speed.

 

[John Koehrer]

Are you getting a voltage out on the leads?
If it's an old enough unit, they had some problems with older boards.

 

[hoffy]

Are you getting a voltage out on the leads?
If it's an old enough unit, they had some problems with older boards.

Thats what I am experiencing. I also can't see or hear any activity with the relay

 

[hoffy]

It seems logical but you could accomplish the same thing without making your own PCB. Find a reversible Electronic Speed Control meant for an RC Car or Robot like this. Then connect the input voltage of the Speed Control to the 24VDC source on the Jobo (or to your own 24VDC source), connect the outputs to the motor and the control inputs to a microcontroller or RC transmitter that can control the speed.

Thats actually very interesting. I really wonder how you could implement it without having to use the RC controller....

I might have to do some more investigation (I am not that clued into electronics, unfortunately)

 

[domaz]

A microcontroller like the Arduino could easily generate the servo signals for the speed controller. That's a better approach than the RC controller and there are many Arduino code examples and tutorials out there. There might be an easier way than that but I can't find anything.

 

[hoffy]

Yippee Kye Aye.....I found the problem! Should have been the first place I looked. It appears that I have a bung power supply. From what I can tell, there is a dual output voltage of 9 and 18 volts DC. I measured across the poles and nothing! I connected my lab supply on the red and yellow wires and all works well (connecting the other circuit, though, gave me not much at all. I am assuming that I need everything connected to get it to work). The micro switch seems to work, so it reverses nicely, the motor seems strong. For now (until I fry the circuit), if I want to slow the rotation, I just turn the volts down. It won't be ideal, but meh, it will get me going.

Cheers