Deltabar PMD75B HART
Product description
Hauser
11
3
Product description
3.1
Product design
3.1.1
Measuring cell for differential pressure with metal process
membrane
+ -
p
1
p
1
1
2
3
4
4
p
2
p
2
A0043083
1
Measuring element
2
Middle diaphragm
3
Filling oil
4
Process membrane
p
1
Pressure 1
p
2
Pressure 2
The process membranes are deflected on both sides by the acting pressures. A filling oil
transfers the pressure to a side of the measuring element where a resistance bridge is
located (semiconductor technology). The differential-pressure-dependent change of the
bridge output voltage is measured and further processed.
3.1.2
Flow measurement
Flow measurement with Deltabar and differential pressure sensor:
Q
Q
Q ~
Q ~
∆
∆
p
p
+
+
–
–
p
1
p
1
p
2
p
2
A
B
A0038340
A
Orifice plate
B
Pitot tube
Q
Flow
Δp Differential pressure, Δp = p
1
– p
2
Advantages:
• A customized unit can be specified.
• Low flow cut off: when activated, this function suppresses small flows which can lead to
large fluctuations in the measured value.
