PROFIBUS Power Hub Segment Coupler 3 (SK3)
PROFIBUS Commissioning
2
016-
10
31
5.2.4
Retry Limits
Adjusting the Retry Limit for Fiberoptical Communication
If the coupling from PROFIBUS DP to PA is designed redundantly and the DP bus uses optical
fiber as a communication medium, Fuchs recommends increasing the retry limit of the
DP master.
Recommended retry limits corresponding to various baud rates:
5.2.5
Device Type Manager (DTM): Installation and Commissioning
System requirements for installation, commissioning, and operation of the DP/PA gateway
device type manager (DTM):
■
Hardware requirements based on your FDT frame application
■
FDT frame application (FDT specification 1.2)
■
Latest version of the HD2-GTR-4PA DTM
■
40 MB free hard drive storage
Installing the DTM Package with PACTware
TM
(Example)
In order to install the DTM package on your system, proceed as follows:
1. Install the P+F-FieldConnex
®
DTM package.
2. Start the PACTware
TM
program.
3. Update the device catalog.
Note!
Cycle Time Discrepancy in Realworld Applications
This is the basic cycle time under ideal conditions. In reality, acyclic communication, retries,
and diagnostic data can increase the cycle time, requiring an additional safety margin to be
added.
For the calculation of an overall cycle time (change of a measured signal until reaction of an
actuator), additional parameters like the measurement cycle time of the PROFIBUS PA devices
and IO processing cycle of the controller must be considered.
Baud Rate
Retry Limit
45.45 kBd
2
93.75 kBd
2
187.5 kBd
2
1.5 kBd
2
3 kBd
4
6 kBd
6
12 kBd
7
