Campbell 61302V Instruction Manual - page 11
61302V Barometric Pressure Sensor
Multipliers to convert the hPa reading to different units
For
Multiply by
kPa 0.1
Mm of Hg
0.75006
In of Hg
0.02953
mBar 1.0
PSI 0.0145
The weather service and most airports correct the pressure
reading at a particular station to what it would be if that station
were located at sea level. This is done so that weather forecasters
can obtain a clearer picture of what is happening in the
atmosphere.
The following equation is used in the program examples to
determine the pressure correction factor. This can then be added
to the measured value. Because barometric pressure is greatly
affected by elevation, the elevation of the site used in the equation
should be as accurate as possible. Where Elevation is in meters
above sea level.
P = 1013.25 [ 1 – ( 1 – Elevation/44307.69231 ) ^5.253283 ]
5.1.
Serial Output Program Example
The program example illustrates the polling of a 61302V in its
default configuration using a CR1000 datalogger.
Communications will occur on serial port COM1. The sensor is
powered for one minute before the top of each hour, at which time
the sensor is polled for a measurement. The program also
includes the option to correct for elevation. The measurement
units in the example are hPa.
'CR1000 Series Datalogger
' Jumper P1 will need to be set to Polled mode (jumpers B & C in place)
' Jumper P3 will need to be set to "Fixed" modes (as per Appendix A)
' Jumper P4 will need to be set to Serial mode (A position)
' Baud 9600, 8 bit, 1 stop, no parity.
'61302V Wiring
'Red - CR1000 SW12V (Unit can be powered continuously if power consumption is not an
issue)
'Black - CR1000 G
'Blue - CR1000 C1 (Tx)
'White - CR1000 C2 (Rx)
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