3 programming, 1 conversion factors, Programming – Campbell Scientific CS100 Barometric Pressure Sensor User Manual

Page 17: Conversion factors, Options, 3. multipliers, And offsets

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CS100 Barometric Pressure Sensor

7.3 Programming

The CS100 sensor is measured using the singled-ended voltage measurement
instruction (VoltSE() in CRBasic and Instruction 1 in Edlog).

Atmospheric pressure changes little with time. In most weather station
applications measuring pressure once an hour is adequate.

7.3.1 Conversion Factors

In the example programs, the pressure is reported in millibars (mb). To report
pressure in different units, multiply the measured pressure by the appropriate
conversion factor using the P37 (Z=X*F) instruction for CR500, CR510,
CR10(X), CR23X, 21X, and CR7, or by adding an expression for CR200(X),
CR800, CR850, CR1000, CR3000, CR5000, and CR9000(X) dataloggers. See
TABLE 7-2 below for conversion factors.

TABLE 7-2. Conversion Factors for

Alternative Pressure Units

To Find

Multiply by

hPa 1.0
kPa 0.1
mm of Hg

0.75006

in of Hg

0.02953

Psi 0.0145
Atm 0.00099
Torr 0.75006

7.3.2 Multipliers and Offsets for Different Measurement Range Options

Please refer to the table below for proper multipliers and offsets.

TABLE 7-3. Multipliers and Offsets

Range Options

Multiplier

Offset

600 to 1100 mb
(Standard range)

0.2 600

500 to 1100 mb

0.24

500

800 to 1100 mb

0.12

800

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