Configure the pa master – Rockwell Automation 1788-EN2PAR EtherNet/IP and ControlNet to PROFIBUS PA Linking Device User Manual User Manual
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Rockwell Automation Publication 1788-UM058B-EN-P - September 2014
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Set Up in the Studio 5000 Logix Designer Application
Chapter 2
Configure the PA Master
Topology Mode
Choose the correct topology mode for the application. The graphical
representation must match the actual topology. See
for available
options. Use this setting to configure redundant linking devices, redundant PA
media, and the internal PA segment terminators.
PA Node
The PA master (linking device) needs a node number to operate on the PA bus.
The default is node number 1.
Max Scan Address
When the linking device is operating, a background scan probes each unused
node number to see if any new field devices were connected. The background
scan runs to the max scan address, then restarts at one.
Slave Timeout
The time in milli-seconds (ms) that the PA master gives for a reply from a field
device before retrying the request.
Slave Retry
The slave retry limit sets the number of times the PA master re-requests data
before dropping the connection. The default setting is 5.
Class 2 MPPF
Used to determine the minimum amount of acyclic data requests allowed per
cyclic scan.
Slew Compensation
TIP
This process also determines the max scan address for the scan function
(see
Scan on page 30
).
IMPORTANT
If the timeout is set too low, some field devices will not be able to reply in time,
and packets could be lost. If the timeout is set too high and a field device has
gone offline, it might take a long time before the PA master will time out that
field device.
IMPORTANT
Do not modify the default setting. Communication slows down if the limit is
above 5.
IMPORTANT
To help prevent communication problems, do not adjust this setting.