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DMD870 Digital Stepper Drive User’s Manual
Motion Control Products Ltd.
P a g e
| 22 Tel.: (+44) 01202 599922
Serial Port: Select the serial communication port to which the Drive is connected. The factory
default setting is COM1.
Baud Rate: Select the communication baud rate. The factory default setting is 38400.
Click Open button to establish a connection with the specified settings. When connecting,
you can choose SaveToDrive to download the current parameter settings to the Drive, or to
upload the stored Drive settings into the ProTuner by clicking Tuning > Position Loop on the
menu bar.
Tuning
The user can choose one or two drop-down menu(s) by clicking Tuning, including
CurrentLoop and SystemConfig.
CurrentLoop: In Current Tuning window, the user can tune the Kp (Proportional Gain) and
Ki (Integral Gain) of Drive’s current loop to optimise responses with different motors.
Start/Restart a Step Response test to get an optimum response.
Kp: Proportional Gain. Proportional Gain determines the response of the Drive to current
setting command. Low Proportional Gain provides a stable system (doesn’t oscillate), has
low stiffness, and large current error, causing poor performances in tracking current setting
command in each step like Figure 13. Too large Proportional Gain values will cause
oscillations and unstable systems.
Figure 12: Current Tuning window