GE PACSystems RSTi User Manual page 43

The cable parameters specified for standard Type A bus cables result in the maximum length
of each bus segment for the respective data transfer rate as shown in the below table.
■
Maximum Cable Lengths per Segments
Table 26: Maximum Cable Lengths per Segments
Baud rate 9.6
Maximum
segment
Length in
'm'(m)
Note:
The maximum admissible distance between two bus stations in each PROFIBUS network
can be calculated as follows:
(NO_REP+1)*Segment length,
Where NO_REP =The maximum number of repeaters connected in series (depends on
repeater type).
Example: The repeater manufacture specifications allow nine repeaters to be connected in
series. The maximum distance between two bus stations at a data transfer rate of 1500 kbit/s
is then as follow:
GFK-2746B PACSystems* RSTi PROFIBUS and PROFINET Network Adapter–August 2013
19.2 45.45 93.75
1200 1200 1200
In a PROFIBUS-DP/FMS installation, you must choose a data transfer rate which is
supported by all devices connected to the bus. The chosen data transfer rate then
determines the maximum segment lengths as shown above.
(9+1)*200m=2000 m
Chapter 3. PROFIBUS Network Adapters
187.5 500 1500
1200 1000 400 200
3000 6000 12000
100 100 100
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