Siemens SIMATIC Manual page 81

3.11 Digital input module SM 321; DI 16 x 24 VDC; with hardware and diagnostic interrupts (6ES7321-7BH01-0AB0)
Wiring and block diagram of SM 321; DI 16 x DC 24 V
①
②
③
④
Wiring diagram of the redundant sensor supply
The figure below shows how an additional redundant voltage source can be used to power
sensors using Vs.
Figure 3-4
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
Channel number
Status displays - green
Error displays - red
Sensor supply V -green
S
Backplane bus interface
Wire-break detection
Wiring diagram of the redundant supply of sensors of SM 321; DI 16 x DC 24 V
Digital modules
81