Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set User Manual
Page 100

Chapter 4
Axis Parameters
4-16
It is not always necessary to configure the shared axis as the last axes in
the system. In the above example similar results would have been
achieved by configuring the shared axis as the first axis (1) in the system.
In cases where a digital and analog servo card is used on the same system,
it is not always possible to change the order of the AMPed axes. The AMP
parameter Number of Motors on First Board assigns axes to boards in
the order they are AMPed. An example of when you can not reorder axes
is:
number of axes on first board is three
the shared axis is one of three analog axes on the first board
the remaining two axes are digital axes on the second board
In order to perform the above configuration you must name all three
analog axes as axis 1, 2, and 3. If you named one of the digital axes as axis
1, 2, or 3, the control would attempt to place it on the analog servo card
resulting in a servo configuration error. Correct this complication by
simply switching the order of the servo cards. In the above example attach
the digital servo card as the first servo card and the analog as the second.
This allows you to configure the two digital axes as axis 1 and 2, Number
of Motors on First Board as two, and the shared axis as axis 5.
Shared Axis names and Integrands
Each shared axis must use the same axis name and same axis integrand in
both processes. Machines with dual axes (two or more physical axes
positioned by one axis name) must decouple the dual axis group before a
shared axis, which is a member of the dual group, can change processes
(see your PAL Reference manual for details on decoupling dual axis
groups). Once a dual axis group is decoupled, each axis in the group gets
its own axis name.
Assign integrand names for a dual axis on a dual processing control only
for the master axis and other axes you intend to decouple from the dual
group. When a dual group is decoupled, each slave can use integrand
planer functions (such as circular interpolation) only after the dual group is
decoupled and the slave axis name has been AMPed as a primary or
parallel axis name in the active plane definition. The master axis in the
dual group uses the dual groups integrand letter when decoupled.