Rockwell Automation 1784-PM16SE SoftLogix Motion Card Setup and Configuration Manual - Manual (Page 81)

Publication 1784-UM003A-EN-P – June 2003
Configuring the1784-PM16SE Card 73
The SERCOS ring consists of the drives and axes connected to the
1784-PM16SE motion controller.
Data Rate
Select the baud rate for the SERCOS ring. Your options are:
• Auto Detect – automatically scans to detect the SERCOS ring baud rate
as set by the drive(s).
• 4 Mb – sets the SERCOS ring baud rate to 4 Mb. This value must match
the baud rate set on the drives. All drives included in the ring must be set
to 4 Mbaud.
• 8 Mb – sets the SERCOS ring baud rate to 8 Mb.This value must match
the baud rate set on the drives. All drives included in the ring must be set
to 8 Mbaud.
Cycle Time
This field sets the rate at which drives on the SERCOS ring are updated. Select
the update rate for the SERCOS ring:
• 0.5 ms
Note: Many drives to not support an update rate of 0.5 ms. Check your
drive documentation for appropriate values.
• 1 ms
• 2 ms.
TIP
The settings on this tab are specific to the 1784-PM16SE
motion controller.
IMPORTANT
If drives are set to both 4 and 8 Mbaud rates and the
motion card’s Data Rate is set to 4 Mbaud, it only detects
the 4Mbaud drives and indicates a closed ring. Those drives
set to 8 Mbaud are ignored. When the program is run it
errs because the drives set to 8 Mbaud are not found.
In the above scenario with the motion card’s Data Rate set
to 8 Mbaud, it errs with “Wrong baud rate”.