Siemens SIMATIC NET PROFIBUS - Manual (Page 224)

Passive Components for Electrical Networks
7-28
PROFIBUS Networks SIMATIC NET
6GK1970-5CA20-0AA1 Release 2 05/2000
Cable Lengths
The length of the transmission path on fiber-optic cables is not dependent on the
transmission rate.
Each node on the optical PROFIBUS network has repeater functionality so that the
following distance information relates to the distance between two adjacent,
interconnected PROFIBUS nodes in a bus topology.
The maximum cable length between two PROFIBUS nodes depends on the type
of fiber-optic cable used.
Table 7-7 Permitted Cable Lengths in Networks with Integrated Optical Interfaces (Bus
Topology)
Fiber-optic cable
SIMATIC NET
PROFIBUS
Maximum cable
lengths between two
nodes (in m)
For 1 Network (= 32
nodes) (in m)
Plastic fiber-optic,
duplex cord 50 1550
Plastic fiber-optic,
standard cable 50 1550
PCF fiber-optic,
standard cable 300 9300
Table 7-8 Permitted Cable Lengths in an OLM Network
Fiber-optic cable
SIMATIC NET
PROFIBUS
Maximum cable
lengths between two
nodes (in m)
For 1 Network (= 32
nodes) (in m)
Plastic fiber-optic,
duplex cord 50 1550
Plastic fiber-optic,
standard cable 80 2480
PCF fiber-optic,
standard cable 400 12400