
AChapterPassive Components for Optical Networks
5-2
SIMATIC NET Twisted-Pair and Fiber-Optic Networks
C79000-G8976-C125-02
5.1 Optical Transmission Technique
Fiber-Optic Cables (FO)
On fiber-optic cables (FO) data is transmitted by modulating electromagnetic
waves in the range of visible and invisible light. The material used is high-quality
glass fiber.
This section describes only the SIMATIC NET fiber-optic cables intended for
Industrial Ethernet. The various FO types allow flexible solutions with which
components can be interconnected depending on the operating and environmental
conditions.
Compared with electrical cables, fiber-optic cables have the following advantages:
Advantages
S Electrical isolation of nodes and segments
S No grounding problems
S No shield currents
S Transmission path immune to external electromagnetic noise
S No lightning protection required
S No noise emission along the transmission path
S Light weight
S Depending on the fiber type, cables several kilometers long can be used even
at higher transmission rates.
Point-to-Point Link
Fiber-optic technology only allows the implementation of point-to-point links; in
other words, one transmitter is connected to only one receiver. The transmission
path between two nodes requires two fibers (one for each transmission direction).
All SIMATIC NET standard fiber-optic cables are therefore designed as duplex
cables.
Comentarios a estos manuales