Siemens SIMATIC S7-1500 Manual page 39

PROFIBUS interface X4
The table below shows the terminal assignment of the PROFIBUS interface. The assignment
corresponds to the standard assignment of an RS485 interface.
Table 3- 1
Note
Supply of I/O devices
The CPU 1518-4 PN/DP MFP does not provide a 24 V DC power supply on the PROFIBUS
interface. I/O devices (for example, PC adapter USB 6ES7972-0CB20-0XA0) are 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. This means it does not need 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 "Connecting the CPU" and
"Accessories/spare parts" in the S7-1500, ET 200MP
(http://support.automation.siemens.com/WW/view/en/59191792) system manual.
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Manual, 12/2017, A5E40882737-AA
PROFIBUS interface terminal assignment
View
1
2
3
4
5
6
7
8
9
Signal name
- -
- -
RxD/TxD-P Data line B
RTS Request To Send
M5V2 Data reference potential (from station)
P5V2 Supply plus (from station)
- -
RxD/TxD-N Data line A
- -
Connecting up
Designation
39