Advanced Adjustment Functions; Bias Function (Position) - Omron R88M-W User Manual

Operation
4-8

Advanced Adjustment Functions

4-8-1

Bias Function (Position)

H Functions
• The bias function shortens positioning time by adding bias revolutions to speed commands (i.e., com-
mands to the speed control loop).
• If the residual pulses in the deviation counter exceed the setting in Pn108 (bias addition band), the
speed set in Pn107 (bias rotational speed) is added to the speed command, and when the residual
pulses in the deviation counter are within the setting in Pn108, adding to the number of bias rotations
stops.
H Parameters Requiring Settings
Parameter No.
Pn107 Bias rotational
speed
Pn108 Bias addition
band
Note 1. When not using the bias function, set Pn107 to 0.
Note 2. If the bias rotational speed is set too high, it will cause Servomotor operation to be unstable.
The optimum setting depends on the load, the gain, and the bias addition band, so adjust the
setting while observing the Servomotor response. (Begin with a bias setting of Pn107 = 0, and
gradually increase it.)
H Setting Procedure
• Complete the gain adjustment before adjusting the bias.
• Increase the Pn107 (bias rotational speed) setting until positioning time is minimal. At this point, if
there are no problems with using overshoot, adjustments are complete.
• If the overshoot is too large, increase Pn108 (bias addition band) to reduce it.
H Operation
Servomotor speed
Note Refer to Position Loop Block Diagram in 4-7-2 Manual Tuning for the internal processing block
configuration.
Parameter
name
Set the rotation speed to be added to the bias
(setting range: 0 to 450 (r/min.)).
Set the residual pulses to be added to the number
of bias rotations using command units (setting
range: 0 to 250 (command units)).
Pn107 added to speed command
when residual pulse exceeds Pn108.
Explanation
Speed command (command
pulse frequency)
Chapter 4
Reference
4-4-4 Parameter
Details
Bias function OFF
Bias function ON
4-109