User Manual
Chapter 8
GFK-1742F
Jan 2020
Follower Motion
229
8.8
Disabling the Follower with External Input
Any CTL bit CTL01- CTL32 can be configured as a Disable Trigger for the follower axis. The
trigger input is tested only when the Enable Follower %Q bit is ON. When the Enable Follower
%Q bit is ON, an OFF to ON transition of the trigger bit will disable the follower. Turning OFF
the Enable Follower %Q bit immediately disables the follower, regardless of the disable
trigger configuration.
8.9
Follower Disable Action Configured for
Incremental Position
Configuring the Follower Disable Action for Inc Position allows the follower axis to perform
an Incremental Registration Move. Disabling the follower with the Enable Follower %Q bit or
optional Disable Trigger will cause the axis to continue at its present velocity, then
decelerate and stop after a specified distance has elapsed. The incremental distance is
specified in a parameter register for each axis:
P227 = Axis 1 Incremental distance
P235 = Axis 2 Incremental distance
P242 = Axis 3 Incremental distance
P250 = Axis 4 Incremental distance
The incremental distance represents the total actual position change that will occur from
the point where the follower is disabled until it stops. Superimposed motion commands
(Jog, Move at Velocity or Motion Programs) should not be active during a Follower
Registration Move.
8.10
Follower Axis Acceleration Ramp Control
For applications where the Follower is enabled after the Master command is already up to
speed, the Follower Ramp feature can be used to apply a controlled acceleration rate to
bring the follower axis up to speed. This may be done without losing any Master command
counts from the point at which the Follower was enabled. During the automatically
generated Follower Ramp Control make-up move, the acceleration/deceleration does not
exceed the configured Follower Ramp Acceleration value and provides a smooth motion.
When the follower is enabled, the slave axis is ramped up to the master velocity at the active
configured Follower Ramp Acceleration rate. This function is most useful when the master
source is in motion before the follower mode is enabled. In addition to the host controller
Enable Follower %Q bit, a CTL bit (CTL01-CTL32) may be configured as the enable follower
signal for position registration functions. When the Enable Follower %Q bit is ON, then the
CTL bit chosen acts as a rising edge trigger to enable follower mode. After Follower is
enabled, only the host controller Enable Follower %Q bit controls the active state of the
following function. When the follower axis is enabled to a moving master source, some
master source counts cannot be used immediately. The master counts that accumulate
during acceleration of the follower axis are stored. When the follower axis reaches the