Rockwell Automation GMLC Reference Manual - Manual (Page 255)

Publication GMLC-5.2 - November 1999
218 Motion Blocks
When you select Synchronize with next Gear Axes, the block
immediately following the current Gear Axes block must be another Gear
Axes block, otherwise GML Commander does not let you connect the
two blocks. In the example above, Synchronize with next Gear Axes
should be selected in the first three Gear Axes blocks—but not in the last
block—to start all four axes simultaneously.
Using the Gear Axes Block
Changing Master Axes
You can change the master axis for electronic gearing at any time, even
while gearing is currently enabled. But be careful, because electronic
gearing can be enabled on more than one axis at a time. When a servo
master axis and slave axis are reversed, the axes become cross-coupled
and unexpected motion may result.
For example, if you are gearing Axis 0 to Axis 1 (defined as a Servo axis)
and then decide to change to gearing Axis 1 to Axis 0, you must first
disable gearing on Axis_0. This is because specifying Axis 1 as the slave
axis with Axis 0 as the master axis does not automatically disable Axis 0
from being a slave axis with Axis 1 as the master axis. See the Disable
Gearing section in this chapter.
!
ATTENTION: Changing virtual master axes on the fly can
result in a temporary stoppage of motion on the Master Axis.