I/O Terminal /
MOUNTING AND WIRING
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3.5.4 Connection of Fieldbus Box Modules
The connection of the Fieldbus Box modules is done direct or via a T-piece (or Y-piece).
The B318 series does have a male and female connector, that means no external T-piece is
required. The supply voltage (+5VDC) for the termination resistor is only supplied via the
female M12 connector. The termination resistor is only available with male connector,
therefore the incoming PROFIBUS line should end in a female connector.
Two T-pieces are available:
+5VDC on male and female connector for the termination resistor
+5VDC only on the female connector
3.6 PROFIBUS
Cabling
Physical aspects of the data transmission are defined in the Profibus standard (see Profibus
layer 1: Physical Layer).
The types of area where a fieldbus system can be used is largely determined by the choice of
the transmission medium and the physical bus interface. In addition to the requirements for
transmission security, the expense and work involved in acquiring and installing the bus cable
is of crucial significance. The Profibus standard therefore allows for a variety of
implementations of the transmission technology while retaining a uniform bus protocol.
3.6.1 Cable-Based
Transmission
This version, which accords with the American EIA RS-485 standard, was specified as a
basic version for applications in production engineering, building management and drive
technology. A twisted copper cable with one pair of conductors is used. Depending on the
intended application area (EMC aspects should be considered) the screening may be
omitted.
