Siemens S7-300 Installation And Operating Manual page 233

Wiring scheme C: 4-wire transducer, internal sensor supply
Particularity:
● Short circuit between sensor supply voltage Vsn and Mn+ is handled.
● It is possible to detect an undervoltage at the transducer by reading back the sensor
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
supply in the module.
Figure 9-24 4-wire transducer, internal sensor supply
9.3 SM 336; F-AI 6 x 0/4 ... 20 mA HART
Analog modules
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