Endress+Hauser Cerabar S PMC 731, Руководство по эксплуатации

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1 Introduction
Applications The Cerabar S pressure transmitter measures the pressure of gases, steam/vapour and
liquids and can be used in all areas of chemical and process engineering.
Operating principle
Ceramic sensor
The system pressure acts directly on the
rugged ceramic diaphragm of the pressure
sensor deflecting it by a maximum of 0.025
mm. A pressure-proportional change in the
capacitance is measured by the electrodes
on the ceramic substrate and diaphragm.
The measuring range is determined by the
thickness of the ceramic diaphragm.
Metal sensor
The process pressure deflects the
separating diaphragm with a filling liquid
transmitting the pressure to a resistance
bridge. The bridge output voltage, which is
proportional to pressure, is then measured
and processed.
Level measurement
The hydrostatic pressure of a column of
liquid enables its level to be measured
continuously by a pressure transmitter if the
density
ρ
of the liquid is known.
0 - 10 bar
0 - 10 bar
0 - 10 bar
Version with
thread
PMC 731
PMP 731
Version with
diaphragm seal
for flange mounting
PMP 635
Version with
diaphragm seal
for hygienic applications
PMC 631
BA187Y04
Figure 1.1
Examples of the Cerabar S
pressure transmitter
BA187
Y05
Ceramic
support
Electrode
Resistance
bridge
Filling fluid
Diaphragm
Diaphragm
Ceramic
measuring cell
Metallic
measuring cell
Figure 1.2
Ceramic and metallic measuring cell
h =
p
hydr
ρ
•
g
Cerabar S 1 Introduction
Hauser 9