User manual

Rockwell Automation Publication MOTION-UM003F-EN-P - March 2015 65
Configure Integrated Motion Using a PowerFlex 755 Drive Chapter 2
Set the Base Update Period
The Base Update Period is basically the RPI rate for Ethernet communication
between the controller and the motion module, a Unicast connection. It also sets
the motor feedback that is returned from the drive in the drive-to-controller
connection.
There are two alternate update periods that you can configure when using Axis
Scheduling. See Configure Axis Scheduling on page 77
for details.
The Base Update Period is how often the motion planner runs. When the motion
planner runs, it interrupts most other tasks regardless of their priority. The
motion planner is the part of the controller that takes care of position and
velocity information for the axes.
Follow these steps to set the Base Update Period.
1. Click the Attribute tab in the Motion Group Properties dialog box.
2. Set the Base Update Period to 3.0…32.0 ms.
For the PowerFlex 755 drive, the minimum Base Update Rate 3 ms.