Emerson DSM314 - Page 430

User Manual Appendix D
GFK-1742F Jan 2020
Tuning Digital and Analog Servo Systems 419
4. Use the configuration software to set the desired user scaling factors and other
configurable parameters. The following items MUST be changed from the default
configuration settings:
Configuration Item
Setting
Axis 1 Mode
Digital Servo
Motor Type:
Select from Table in Chapter 4
Position Loop Time Constant:
60 ms
Velocity Loop Gain:
(Load Inertia / Motor Inertia) * 16
User Units : Counts (Standard Mode Only)
See Chapter 3
Position Error Limit:
30000 x User Units / Counts
Set the configuration parameters in the order shown above.
5. Store the configuration to the host controller.
6. Clear the program from the host controller, turn off all DSM314 %Q bits and place
the host controller in RUN mode. Monitor the %I CTL bits for Home Switch, (+)
Overtravel and (-) Overtravel and confirm that each bit responds to the correct
switch (Refer to Chapter 5 for %I bit definitions).
7. Turn on the Enable Drive %Q bit and confirm that the servo amplifier is enabled. If a
brake is used on the servomotor it should be released at this time.
8. Send the %AQ command code for Force Digital Servo Velocity 100 (rpm). Confirm
that the motor moves in the desired POSITIVE direction and the Actual Velocity
reported in the %AI table is POSITIVE. If the motor moves in the wrong direction, use
the Axis Direction parameter in the configuration software to swap the positive and
negative axis directions.
9. Remove the Force Digital Servo Velocity command from the %AQ table. Use a low
Jog Velocity and Jog Acceleration in the configuration, values may be increased later.
Turn on the Jog Plus %Q bit. Confirm that the servo moves in the proper direction
and that the Actual Velocity reported by the DSM314 in the %AI table matches the
configured Jog Velocity. If Motion Programs will use an acceleration higher than the
Jog Acceleration, it may be necessary to increase Jog Acceleration so that Abort All
Moves and Normal Stop actions will operate as expected.
10. Use a low value for Find Home Velocity and Final Home Velocity in the module
configuration, values may be increased later. Check for proper operation of the Find
Home cycle by momentarily turning on the Find Home %Q bit (the Drive Enabled %Q
bit must also be maintained on). The axis should move towards the Home Switch at
the configured Find Home Velocity, then seek the Encoder Reference point at the
configured Final Home Velocity. If necessary, adjust the configured velocities and
the location of the Home Switch for consistent operation. The final Home Switch
MUST transition at least 10 milliseconds before the encoder reference point is
encountered. The physical location of Home Position can be adjusted by changing
the Home Offset value with the configuration software.