Measuring Cell For Absolute Pressure From The Gauge Pressure Series; Measuring Cell For Gauge Pressure, Front-Flush Membrane - Siemens SITRANS P DS III Operating Instructions Manual

Description
3.7 Principle of operation
3.7.3.5

Measuring cell for absolute pressure from the gauge pressure series

①
②
③
Image 3-9
The inlet pressure (p
diaphragm
changes the resistance of the four piezoresistors (bridge circuit) of the absolute pressure
sensor. The change in the resistance causes a bridge output voltage proportional to the inlet
pressure.
3.7.3.6

Measuring cell for gauge pressure, front-flush membrane

①
②
③
④
Image 3-10
The inlet pressure (p
④
and the filling liquid
34
Measuring cell
Process connection
Seal diaphragm
Function chart of measuring cell for absolute pressure
) is transferred to the absolute pressure sensor
e
③
and the fill fluid
Reference pressure opening
Measuring cell
Process connection
Seal diaphragm
Function chart of the measuring cell for gauge pressure, flush mounted diaphragm
) is transferred to the gauge pressure sensor
e
⑤
, displacing its measuring diaphragm. The displacement changes
④
⑤
P
e
④
, displacing its measuring diaphragm. The displacement
⑤
Filling liquid
⑥
Gauge pressure sensor
p Inlet pressure
e
Operating Instructions, 02/2016, A5E00053276-08
Filling liquid
Absolute pressure sensor
Inlet pressure
⑤
via the seal
⑥
via the seal diaphragm
SITRANS P DS III/P410 with PROFIBUS PA