Maximum Cable Length Of A Segment In A Profibus Network; Network Repeaters - Siemens SIMATIC S7-200 System Manual

The maximum length of a PROFIBUS network segment depends on the baud rate
and the type of cable used. Table 7-7 lists the maximum segment lengths for cable
matching the specifications listed in Table 7-6.
Table 7-7
9.6 kbaud to 93.75 kbaud
1 Mbaud to 1.5 Mbaud

Network Repeaters

Siemens provides network repeaters to connect PROFIBUS network segments.
See Figure 7-25. The use of repeaters extends the overall network length, allows
you to add devices to a network, and/or provides a way to isolate different network
segments. PROFIBUS allows a maximum of 32 devices on a network segment of
up to 1,200 m (3,936 ft.) at 9600 baud. Each repeater allows you to add another 32
devices to the network and extend the network another 1,200 m (3,936 ft.) at
9600 baud. Up to 9 repeaters may be used in a network, but the total length of the
network can be no more than 9600 meters. Each repeater provides bias and
termination for the network segment. See Appendix E for ordering information.
32 Devices/1,200 m (3,936 ft.)
Figure 7-25
S7-200 Programmable Controller System Manual
A5E00066097-02
Setting Up Communications Hardware and Network Communications

Maximum Cable Length of a Segment in a PROFIBUS Network

Transmission Rate
187.5 kbaud
500 kbaud
3 Mbaud to 12 Mbaud
CPU CPU
Network with Repeaters
Maximum Cable Length of a Segment
1,200 m (3,936 ft.)
1,000 m (3,280 ft.)
400 m (1,312 ft.)
200 m (656 ft.)
100 m (328 ft.)
Repeater
CPU CPU
32 Devices/1,200 m (3,936 ft.)
Repeater
7-35