310201g Analog Differential Pressure Measurement Flashcards
What are the two reference points used in pressure measurement?
- Absolute pressure
- Gauge pressure
What is another term for vacuum?
Negative gauge pressure
What is the equation to calculate the absolute pressure on a positive gauge pressure?
Absolute pressure = gauge pressure + atmospheric pressure
Why is temperature compensation necessary in a mechanical differential pressure gauge?
Because a change in temperature can effect the elasticity properties of the diaphragm or bellows
Differential pressure switches can be constructed using diaphragms or pistons to sense the pressure.
The sensor used for high pressure applications is the _______
The sensor used for high pressure applications is the piston
As the distance between the plates of a capacitance pressure transducer is increased, the capacitance produced increases or decreases?
The capacitance produced decreases as the distance beteeen the plates of a capacitance pressure transducer increases
Define pressure
Pressure is defined as the force exerted over a unit area
Pressure = force ÷ area
What is the equation for calculating absolute pressure from a vaccuum pressure gauge?
Absolute pressure = atmospheric pressure - vaccuum pressure
Differential pressure measurement devices can measure what four functons?
- Flow - pressure drop across a fixed restriction
- Liquid level - pressure related to the height of a liquid in a vessel
- Fluid density
- Filter status
Differential pressure switched are constructed with diaphragms and pistons
Which construction type is used for lower pressures?
Diaphragms
What are the two common measuring elements in electronic differential pressure transmitters?
- Strain gauge pressure transducers
- Capacitance pressure transducers
