Position Data - Omron CS1W-MC221 - 02-2008 Operation Manual

Position Data

Position Loop FF Gain
Speed reference pulses
Backlash Correction
Brake ON/OFF Time
3-4 Position Data
If the position loop gain is too low, motor response will deteriorate because
there will be too many accumulated pulses. If the position loop gain is too
high, oscillation and noise might occur. In general, the setting should be 50 to
70 (1/s) for NC machine tools, 30 to 50 (1/s) for multi-purpose machines and
assembly machines, and 10 to 30 (1/s) for industrial robots.
The setting range is 1 to 250 and the default setting is 40 (1/s).
Sets the position loop FF (feed-forward) gain. The setting range is 0 to 100
(%), and the default setting is 0 (%).
The position loop FF gain process the speed reference pulses and reduces
the positioning time by adding directly to the command voltage.
Position
loop FF
gain
Error Position
counter loop gain
The following diagram shows the relationship between the position loop FF
gain and the speed reference pulses.
Command
voltage
This parameter sets backlash correction for the mechanical system. The set-
ting range is 0 to 10,000 pulses and the default setting is 0 pulses. Refer to
6-15 Backlash Correction for more details.
This parameter sets the brake ON/OFF time. The setting range is 0 to 10,000
ms and the default setting is 0 ms. Refer to the brake manual and adjust the
proper time for the system.
Refer to Servo Lock (page 241) and Servo Unlock (page 241) in 5-3 PLC
Interface Area and 6-14 Servo Lock and Unlock.
There are 2,000 positions that can be used. An axis is positioned by specify-
ing the position directly in a G-language program or it is positioned by specify-
ing a position in the position data (specifying indirectly). Position data is
transferred to and from an MC Unit by writing a specific transfer command in
the command area (addresses 6102/6103) using CX-Motion, IOWR/IORD
instructions or IOWR instructions.
Amplifier
Command
voltage
Feedback pulses
Position loop FF gain 100%
Position loop FF gain 50%
Speed reference pulses
Max. speed reference value
(Max. motor speed)
Section 3-4
Servo
driver
187