Allen-Bradley Kinetix 5500, Reference Manual, Page: 44 / 497

Chapter 2
Behavior models used in CIP Motion
44
Rockwell Automation Publication MOTION-RM003I-EN-P - February 2018
SERCOS versus CIP
For a SERCOS axis with absolute feedback, the drive scaling function and
absolute position is maintained in the drive and therefore may be easily restored in
the control after a power cycle or download of a new project by simply reading the
position from the drive.
By contrast, a CIP Motion axis supports controller based scaling where absolute
position is maintained in the controller’s firmware. Without the work of the APR
feature, absolute position would be lost after a power cycle or project download.
See also
APR Fault Conditions on page 44
APR Fault Examples on page 47
APR Fault Generation on page 45
APR Fault Attributes on page 279
The Absolute Position Recovery is not retained after the following:
•
A project is exported, saved as a .L5K or .L5X, and imported (downloaded).
•
A major non-recoverable fault (MNRF).
•
A power loss.
•
On a Control Logix 5570 controller without an ESM
Tip: The APR can potentially be restored from a Secure Digital Card on a ControlLogix
5570 Controller (if a 1756-ESM is not present).
•
A download of an axis that does not have its home bit set.
•
Power cycling of an incremental encoder.
See also
Absolute Position Recovery on page 43
APR Recovery Scenarios on page 48
APR Fault Examples on page 47
Absolute Position Recovery (APR) faults are generated during these events and
when one of the conditions defined below occurs.
In order for an APR Fault to occur, the axis must be in the homed state. The Axis
Homed Status Bit must be set.
Absolute Position Loss without APR
Faults
APR Fault Conditions