Siemens SIMATIC PCS 7 Configuration page 27

2 Configuring and wiring
2.3 Redundant connections of the distributed I/O
Connection and schematic circuit diagram of the SM 331; AI 8 x 16 bit (current
measurement)
For current measurements, the voltage terminals are closed in parallel with the
corresponding current sensing resistor. Bridge the channel input terminals with
the adjacent connector terminals.
For example, to configure channel 0 for the current measurement, you have to
bridge the terminals 22 and 2 and the terminals 23 and 3.
At the channel configured for current measurements, connect the current sensing
resistor to the adjacent channel terminals in order to achieve the specified
precision.
4-wire transducer (channel 0) or
2-wire transducer with external power supply (channel 7)
Figure 2–11
Configuration of Redundant I/O Modules
Entry-ID: 28430682, V2.0, 03/2015
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