Siemens SIMATIC NET PROFIBUS User Manual
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PROFIBUS Optical Bus Terminal (OBT)
C79000-G8976-C122-02
C79000-G8976-C122-02
Introduction
The PROFIBUS OBT (Optical Bus Terminal) is a network component for use in
optical PROFIBUS DP fieldbus networks. It allows the attachment of a single
device without an integrated optical interface to the optical PROFIBUS DP. The
following figure illustrates a typical configuration.
optical PROFIBUS DP fieldbus networks. It allows the attachment of a single
device without an integrated optical interface to the optical PROFIBUS DP. The
following figure illustrates a typical configuration.
1) PROFIBUS cable (terminated at both ends)
2) Plastic FO cable or PCF FO cable with two fibers
2) Plastic FO cable or PCF FO cable with two fibers
PC
Programming Device
Programming Device
Operator Panel
SIMATIC S7-400
with IM 467 FO
with IM 467 FO
ET 200M with
FO interface
DP node without
FO interface
FO interface
2)
1)
2)
2)
1)
OBT
OBT
À
À
À
À
À
Terminating resistor activted
Figure 1-1
Example of an Optical PROFIBUS DP Configuration
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