Siemens SIMATIC S7-1500 Manual page 41

Block diagram
The following figure shows the block diagram of the CPU 1518-4 PN/DP MFP.
①
Display
②
RUN/STOP/MRES mode selector
③
Electronics
④
PROFINET 2-port switch
⑤
PROFIBUS DP driver
⑥
Backplane bus interface
⑦
Internal supply voltage
X50 SIMATIC memory card
X80 24 V DC Infeed of supply voltage
PN X1 P1 R PROFINET interface X1 Port 1
Figure 3-3 Block diagram of the CPU 1518-4 PN/DP MFP
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Manual, 12/2017, A5E40882737-AA
PN X1 P2 R PROFINET interface X1 Port 2
PN X2 P1 PROFINET interface X2 Port 1
PN X3 P1 PROFINET interface X3 Port 1
PB X4 PROFIBUS interface X4
L+ 24 V DC supply voltage
M Ground
R/S RUN/STOP LED (yellow/green)
ER ERROR LED (red)
MT MAINT LED (yellow)
X1 P1, X1 P2, LED Link TX/RX
X2 P1, X3 P1
Connecting up
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