Yaskawa Fully Closed Loop Control Control (Dual Loop, Glass Scale, External Encoder)

Excel calculator

MachMotion Technical Support:

See this page with these documents attached if you are not able to access the server.  Always use the versions from the server when possible to guarantee the most recent versions.

Yaskawa Fully Closed Loop documents from the server.

Use the calculator on the server to get Yaskawa Drive parameters, and steps per settings for Mach

M:\Support\Machine Calibration\Yaskawa Fully Closed Loop

Also see this folder for encoder config files, as well as some info on each encoder in the .txt files

M:\Support\Machine Calibration\Yaskawa Fully Closed Loop\Universal Card Config Files

In tuningless mode, you likely will have to adjust the rigidity: Yaskawa Mini Manual. 

You can test the encoder on large machines by jogging here and making sure feedback pulse counter and Fully closed feedback pulse counter go the same direction. You have to turn off drive enable from the control but leave on hardware enable. 

Manually Tune Servo Gains

If auto tuning doesn't work, you may have to manually tune the servos. 

Turn off Tuning-less Function in the drive

Set Pn170.0 to 0 to disable the auto gain adjustment

PN100 Speed loop Gain.  Lower numbers means softer

PN101 Speed Loop Integral Time Constant.  Higher number means softer

PN102 Position loop Gain.  Lower numbers means softer

Calculate the Moment of Inertia Ratio

Run the first step of Auto Tuning with SigmaWin to calculate the Moment of Inertia Ratio and save that to the drive.  Also verify that the calculated percent is less than 400, if its greater than 400 then the motor is not sized correctly.

Troubleshooting

To track down encoder issues, you can graph the encoder counts and velocity in Mach4. 

Here's an example of an encoder overflowing. This should never happen but in this case the encoder wasn't configured correctly. 

To see how you are doing while tuning or just overall performance, graph Feedback speed, External encoder speed, and Torque Reference. This allows you to see how much lag there is between the motor and the external encoder... basically shows how backlash is responding. 

Here is how to setup a graph inside Sigmawin:

Here is an example of an average move on a sluggish system (lots of backlash):

In this graph, you can see there's almost an 80 ms delay between the motor and the external encoder (80ms of movement with NO movement on the encoder!). This was on a B axis on a boring mill. 

This is an example of an unstable tune... the gains are too high.