Siemens SIMATIC S7-300 Manual page 263

6.5 Analog input module SM 331; AI 8 x 14 Bit High Speed; synchronous; (6ES7331-7HF0x-0AB0)
Terminal assignment
The following diagrams show different possible forms of wiring.
Wiring: Voltage measurement
Figure 6-7 Block diagram and wiring diagram
Measuring range module settings
S7-300 Automation System Module data
Manual, 08/2006, A5E00105505-04
Measuring range
± 1V
± 5V
± 10V
1...5V
Analog modules
Measuring range module setting
A
B
B (Default)
B
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