Siemens SIMATIC S7-300 Manual page 296

Analog modules
6.8 Analog input module SM 331; AI 2 x 12 bit; (6ES7331-7KB02-0AB0)
Terminal assignment
The following diagrams show different possible forms of wiring. The input impedance is
determined by the set measuring range.
Wiring: Voltage measurement
Figure 6-18
Measuring range module settings
6-62
Wiring and block diagrams
Measuring range
± 80 mV
± 250 mV
± 500 mV
± 1000 mV
± 2.5 V
± 5 V
1 V to 5 V
± 10 V
Measuring range module setting
A
B
S7-300 Automation System Module data
Manual, 08/2006, A5E00105505-04