Endress+Hauser Hart Cerabar PMP71B, Руководство по эксплуатации

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Product description Cerabar PMP71B HART
12 Hauser
Measuring device with a diaphragm seal
p
1
2
3
4
A0043583
1 Measuring element
2 Internal process isolating diaphragm
3 Channel with fill fluid
4 Metal process isolating diaphragm
p Pressure
The process pressure acts on the process isolating diaphragm of the diaphragm seal and is
transferred to the internal process isolating diaphragm by a diaphragm seal fill fluid. The
internal process isolating diaphragm is deflected. A fill fluid transfers the pressure to the
measuring element on which a resistance bridge is located. The pressure-dependent
change in the bridge output voltage is measured and evaluated.
Advantages:
• Depending on the version, can be used for process pressures up to 400 bar (6 000 psi)
and for extreme process temperatures
• High long-term stability
• High overload resistance
• Standard measuring device (without a diaphragm seal): Secondary containment for
enhanced integrity
Applications for diaphragm seals
Diaphragm seal systems are used if the process and the device need to be separated.
Diaphragm seal systems offer clear advantages in the following instances:
• In the case of extreme process temperatures - through the use of temperature isolators
or capillaries
• In the case of strong vibrations - decouple the process from the measuring device by
using a capillary
• In the case of aggressive or corrosive media - through the use of high-durability
membrane materials
• In the case of media that crystallize or contain solids - through the choice of suitable
coatings
• In the case of heterogeneous and fibrous process media
• If extreme measuring point cleaning is necessary, or in the event of very damp mounting
locations
• For mounting locations that are difficult to access