Siemens SIMATIC Manual page 37

Structure of the Sample
Power supply
ON/OFF
Strain relieve
clamp
1st step: Wiring
Warning
!
You risk contacting live wires if the PS 307 power supply module is switched on or
if the power supply line of the PS is connected to mains.
Wire the S7-300 only after you have switched off power!
Step Wire the power supply to the CPU
1 Connect the wired front plug to the CPU and screw fasten it.
2 Connect the voltage supply of the digital I/O:
S
24 V to X2, pin 1 and 31
S
Ground to X2, pin 20 and 40
3 Connect the incremental encoder to the 24–V power supply.
4 Connect the encoder signals (X2, pin 2 ... 4).
5 Connect the relay circuit to the power supply.
6 Connect all lines of the relay circuit (X2, pin 32 to 35 and pin 40).
7 Strip the cable insulation and connect the shielding to the shielding terminator. Use shiel-
ding terminals.
Automation System S7-300, Getting Started – Digital
A5E00105533-01
Line voltage Mode selection switch
trimming
SF
BF
5 V DC
FRCE
RUN
STOP
RUN
STOP
MRES
+
24 Volt
Jumper cables
Profile rail
0 0 0
1 1 1
2 2 2
3 3 3
4 4 4
5 5 5
6 6 6
7 7 7
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
Programming device
with
STEP 7 software
PG cable
3