Siemens Simantic S7-1500 Manual page 31

PROFIBUS interface X3
The table below shows the pin assignment of the PROFIBUS interface. The assignment
corresponds to the standard assignment of an RS485 interface.
Table 3- 1 PROFIBUS interface pin assignment
View
Note
Supply of I/O devices
CPU 1517T-3 PN/DP does not provide a 24 V DC power supply on the PROFIBUS interface.
I/O devices (for example, PC adapter USB) are therefore only operational on the interface in
conjunction with a plug-in power supply set for external power supply.
The innovative successor product, PC adapter USB A2, receives the required power supply
via the USB port. The USB A2 PC adapter therefore does not require a 24 V DC supply
voltage and can be operated without a plug-in power supply set for external power supply.
Reference
You can find additional information on the topics of "Wiring the CPU" and "Accessories/spare
parts" in the S7-1500, ET 200MP
(http://support.automation.siemens.com/WW/view/en/59191792) system manual.
CPU 1517T-3 PN/DP (6ES7517-3TP00-0AB0)
Manual, 12/2017, A5E36285525-AB
Signal name
1 - -
2 - -
3 RxD/TxD-P Data line B
4 RTS Request to send
5 M5V2 Data reference potential (from station)
6 P5V2 Supply plus (from station)
7 - -
8 RxD/TxD-N Data line A
9 - -
Designation
Wiring
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