Siemens SINAMICS G150, Operating Manual

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Operation 11/03
SINAMICS G150
6-30
Operating Manual
PROFIBUS Connection
The PROFIBUS is connected by means of a 9-pin Sub-D socket (X126). The
connections are electrically isolated.
Table 6-4 X126 - PROFIBUS connection
Pin Signal name Meaning Range
1 SHIELD Ground connection
2 M24_SERV Power supply for teleservice, ground 0 V
3 RxD/TxD-P Receive / transmit data P (B/B') RS485
4 CNTR-P Control signal TTL
5 DGND PROFIBUS data reference potential (C/C')
6 VP Supply voltage plus 5 V ± 10 %
7 P24_SERV Power supply for teleservice P, + (24 V) 24 V (20.4 V -28.8 V)
8 RxD/TxD-N Receive / transmit data N (A/A') RS485
1
9
9 - Not used
Connectors
The cables must be connected via PROFIBUS connectors because they contain
terminating resistors.
PROFIBUS connector
without programming
device / PC connection
6ES7972-0BA41-0XA0
PROFIBUS connector
with programming device /
PC connection
6ES7972-0BB41-0XA0
Fig. 6-18 PROFIBUS connectors
Bus Terminating Resistor
The bus terminating resistor must be switched on or off depending on its position in
the bus, otherwise the data will not be transmitted properly.
Principle: the terminating resistors must only be switched on at both ends of the
bus line; the resistors must be switched off at all other connectors.
The cable shield must be connected at both ends with the greatest possible
surface area.