Unigas PBY1025, Manual Of Installation - Use - Maintenance

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22
Duct pressure switches and sensors
Installing differential pressure probes for air
A - Control a filter (clogging)
B - Control a fan (upstream/downstream)
C - Measurement of difference in pressure between two ducts
D - Measurement of difference in pressure between two rooms or
of inside of duct and outside
Basic principles
Measuring static pressure(i.e. pressure exerted by air on pipe
walls)
Measuring dinamic pressure
Legend
y Kg/m3, specific weight of air
q m/s, air speed
g 9.81 m/s2 gravity acceleration
Pd mm C.A., dynamic pressure
Measuring total pressure