The Shop > CNC
Retrofit of an EMCO 120 CNC lathe
David Jupp:
Was there a specific reason for using a flameproof motor, or was it just 'available'? They usually carry a significant price premium and can have a long lead time...
mukanico:
--- Quote from: RotarySMP on March 08, 2019, 04:02:25 AM ---Wonder what the EMCO spindel motor driver interface was? Analog 0-10V?
To replace a DC motor with a AC motor, you normally need to go up significantly in power, not down.
Mark
--- End quote ---
Honestly, I have no clue... When I saw the 400V on the motor tag I decided to use a VFD, as I only had 230V single phase available at my home shop. Probably there was as a way to use the original motor, but I chose the easiest route for me at the time.
--- Quote ---Was there a specific reason for using a flameproof motor, or was it just 'available'? They usually carry a significant price premium and can have a long lead time...
--- End quote ---
No reason at all, just what I found at the time on the local classified ads. It was a new old stock motor that I was able to get for 100€...
PekkaNF:
Very good work. Well done.
--- Quote from: mukanico on March 06, 2019, 07:42:59 AM ---....
For the axes, I chose to use 750W AC servomotors and drivers from DELTA, model ASD-B2-0721-B, to replace the original 5-pole Berger Lahr stepper motors.
....
--- End quote ---
How are those Delta motors/drivers documented and how easy they are to work with?
mukanico:
--- Quote from: PekkaNF on March 08, 2019, 11:11:38 AM ---
How are those Delta motors/drivers documented and how easy they are to work with?
--- End quote ---
Pretty easy, actually. It was my first time using AC servo motors and I found it quite straightforward. They take standard differential pulse/dir signals. The documentation is very well written and the parameters are pretty clear to understand. In addition, DELTA provides a free PC software that you can use to communicate with the driver and setup everything as well as do the tuning.
The only thing to note is that there seems to be a few clones/counterfeits of these motors/drivers going around. To be honest, to this day I'm not sure if I bought the original or the clones. They look and feel too good to be a clone, but since I bought them on Ebay directly from China, I can't be sure of their authenticity.
mukanico:
Hello,
Quick update to this build: I went back to the original motor pulley. I had to increase the VFD max. frequency to 83Hz to reach the original 4000rpm max. spindle speed but the additional low end torque is quite useful.
free image hosting website
Navigation
[0] Message Index
[*] Previous page
Go to full version