Siemens SIMATIC Manual page 355

Wiring: 2-wire and 4-wire transducers for current measurement
Figure 6-14 Block diagram and wiring diagram
Note
The interconnection between M
using grounded 4-wire transducers with non-isolated supply.
Measuring range module settings
Measuring range module in "Current" position
Any voltage measurement will destroy the measuring range module if "current" measuring
mode is set.
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
6.7 Analog input module SM 331; AI 8 x 12 bit;(6ES7331-7KF02-0AB0)
Measuring range
2-wire transducer
4-wire transducer
CAUTION
and M- (terminals 11, 13, 15, 17, 19) is not required when
ANA
4 mA to 20 mA
± 3.2 mA
± 10 mA
0 mA to 20 mA
4 mA to 20 mA
± 20 mA
Analog modules
Measuring range module setting
D
C
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