Electronics - Siemens SITRANS P Operating Instructions Manual

4.4.1

Electronics

①
②
③
④
⑤
⑥
⑦
Mode of operation
● The inlet pressure is converted into an electrical signal by the sensor
● This signal is amplified by the measuring amplifier
converter
● The digital signal is analyzed in a microcontroller
and thermal characteristics.
● The digital signal is then converted in a digital-to-analog converter
of 4 to 20 mA.
A diode circuit provides reverse polarity protection.
SITRANS P320/P420 with 4 to 20 mA/HART
Operating Instructions, 11/2019, A5E44852162-AC
Measuring cell sensor
Measuring amplifier
Analog-to-digital converter
Microcontroller
Digital-to-analog converter
EEPROM
HART modem
③
.
4.4 Functional principle
⑧
Buttons
⑨
Display
⑩
Connection for external ammeter
⑪
EEPROM
I Output current
A
U Auxiliary power
H
①
.
②
and digitized in an analog-to-digital
④
and corrected with regard to linearity
⑤
into the output current
Description
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