About the ILX69-PBM
ILX69-PBM ♦ CompactLogix™ or MicroLogix™ Platform
User Manual
PROFIBUS Master Communication Module
Page 18 of 113
ProSoft Technology, Inc.
If the ILX69-PBM is linked with only one other device on the bus, both devices must be
connected to the ends of the bus line. These devices must deliver the supply voltage for
the termination resistors. If three or more devices are connected to the bus, the ILX69-
PBM can be connected at any desired position.
Up to 32 PROFIBUS devices can be connected to one bus segment, without repeaters.
If several bus segments are linked to each other with repeaters, there can be up to 127
devices on the network.
The maximum permissible cable length of a PROFIBUS segment depends on the baud
rate used, see the following table:
Baud rate in kBit/s
Maximum distance
9.6
1,200 meters 3,940 feet
19.2
1,200 m
3,940 ft
93.75
1,200 m
3,940 ft
187.5
1,000 m
3,280 ft
500
400 m
1,310 ft
1,500
200 m
656 ft
3,000
100 m
328 ft
6,000
100 m
328 ft
12,000
100 m
328 ft
Only PROFIBUS certified cables, preferably the cable type A, should be used. The
following table contains important electrical data concerning PROFIBUS certified cable:
Parameter
Value
Impedance
35 to 165 Ohm at frequencies from
3 to 20 Mhz
Capacity per units
length
< 30 pF/m
Loop resistance
110 Ohm/km
Wire gauge
0.64 mm
