I trickled a few bits of info in some other threads, this one will be dedicated to the upgrade I am doing. I started this upgrade about 3 years ago and got a bit lost, and lost interest. My CNC has been dead since, and I want it back. I am taking a different tact this time so I can be self-sufficient in getting the parts together and working. HUGE thanks go out to James Dressman for all the groundwork he shared with me years ago. I would NOT be in a position to finally pull this off without the information he provided, including the pinouts to the DB9 connector on the Mikini, solid models for the motor mount, and tons of info. 38 emails worth! In the end, though the exact parts he used weren't available, and I was unable to follow exactly in his footsteps.
So, now I am going my own way, integrating an Arduino in between the Mikini/Mach and the VFD. The signals on the DB9 connect will go to the Arduino which will interpret F/W, Run/Stop, and spindle command speed. The Arduino will then command the VFD to perform those actions, interpret the encoder feedback on speed, etc. Here is the schematic as it stands right now:
I have all the signals working in both manual and MACH3 control. I am waiting for delivery of the VFD. I have 3D printed the motor mounts for now, and the "first job" of the upgraded machine will be to make aluminum replacements for the motor mounts. James' models are attached in a ZIP file.
Here are the DB9 pinouts that I know:
- DGND (Ground)
- ENABLE (Run/Stop from Mikini/Mach)
- F/R
- - (????)
- FAULT (Signal fault to the Mikini)
- FOUT (84 PPR signal back to the Mikini)
- maic (PWM out from Mikini/Mach)
- DVCC (????)
- S1 (????)
maic is the PWM signal for spindle command speed. I don't know what S1 is. The rest are pretty well self explanatory. I am only using pins 2, 3, 5, 6 and 7 right now.
I am using a Marathon BlackMAX 2 hp motor from Automation direct, which includes a differential encoder:
https://www.automationdirect.com/adc...duty/y540-a772
The VFD will be this one (ordered, but not received yet):
https://www.automationdirect.com/adc...vfds/gs21-23p0
I am using an Arduino Mega 2560 board, with a demoboard shield:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
For feedback I am using a 4-line OLED display:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
This is driven off the I2C pins on the Arduino and tell me Run/Stop, F/R, Command Spindle Speed, and Actual Spindle speed - all programmed in the Arduino. I will post the Arduino code as I get closer to a final version.
I think that's all for now. I will keep this thread updated as I progress.