User manual

188 Rockwell Automation Publication MOTION-UM003F-EN-P - March 2015
Chapter 8 Home an Axis
This table describes the scenarios whether the APR feature recovers absolute position. In each of these cases marked by Yes,
the APR feature restores absolute position and preserves the state of the Axis Homed bit, indicating that the axis has a
machine referenced absolute position.
Table 26 - APR Recovery Scenarios
Controller Event Machine Reference Retained
Controller removal and insertion under power (RIUP) with a battery
(1)
.Yes
Controller power cycle with battery. Yes
Controller Firmware Update. Yes
Controller update from CompactFlash card. Yes
Controller swap (CompactFlash card also swapped). Yes
Steps
1. Axes are homed.
2. Project saved to CompactFlash or SD card.
3. Axes are moved and rereferenced.
4. System restored from CompactFlash or SD card.
Result
The system absolute position is restored to rereferenced positions and the
Home bit remains set.
Yes
Steps
1. Axes are homed.
2. Project is saved to CompactFlash or SD card.
3. Same CompactFlash or SD card is used on machines 2, 3, 4 ...
4. Axes are homed on machines 2, 3, 4... at different positions.
5. System restore from CompactFlash or SD card on each machine.
Result
The system absolute position on each machine becomes restored correctly at
its respective position and the Home bit remains set.
Yes
Change controller (CompactFlash card not swapped). No
Change controller without a CompactFlash card. No
Controller power cycle without battery. No
Controller removal and insertion under power (RIUP) without battery. No
Take the controllers out of two systems with a battery or energy storage module
and swap controller. There is no CompactFlash or SD cards on either controller.
No
1. Controller remains powered.
2. Power cycle drives.
3. Change feedback device but not motor.
No
Steps
1. Axes are homed.
2. Project is saved to a CompactFlash or SD card.
3. Memory becomes corrupt.
4. System restores from the CompactFlash or SD card.
Result
The system absolute position is lost, the axes must be rehomed, and the Home
bit is cleared.
No
Controller power cycle or removal and insertion under power without a battery
or energy storage module.
No
1. Controller and drives remained powered.
2. Hardware feedback failure on an axis.
No
1. Battery Backed Controller.
2. User program running with an axis that is not homed.
No