Campbell WXT520, Инструкция по эксплуатации

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WXT520 Weather Transmitter
6
6.5 Commands
Campbell Scientific uses the SDI-12 protocol to communicate with the
WXT520. Both "aM!" and "aR!" commands are supported (where "a" is the
sensor address). The preferred command is "aR!", since the communication is
done in fewer steps. The WXT520 is configured to run continuously so the
output is identical. TABLE 6-2 contains the outputs as configured by Campbell
Scientific. All outputs are in SI units.
TABLE 6-2. SDI-12 Commands
SDI-12
Command
Command
Function Values Returned
aR! or aM!
Composite
Message
Wind Direction Average, Wind Speed
Average, Air Temperature, Relative
Humidity, Barometric Pressure, Rainfall
Amount, Hail Amount
aR1! or
aM1!
Wind Message
Wind Direction Minimum, Wind Direction
Average, Wind Direction Maximum,
Wind Speed Minimum, Wind Speed
Average, Wind Speed Maximum
aR2! or
aM2!
PTU Message Air Temperature, Relative Humidity,
Barometric Pressure
aR3! or
aM3!
Precipitation
Message
Rainfall Amount, rainfall Duration,
Rainfall Intensity, Hail Amount, Hail
Duration, Hail Intensity
aR5! or
aM5!
Self
Diagnostic
Message
Supply Voltage, Internal Reference
Voltage
6.6 Programming
6.6.1 CRBasic
Dataloggers that use CRBasic include our CR200(X)-series, CR800, CR850,
CR6, CR1000, CR3000, and CR5000. These dataloggers use the
SDI12Recorder() instruction to read the WXT520.
When using a CR200(X), the SDI12Recorder() instruction has the following
form:
SDI12Recorder ( Destination, Output String, Multiplier, Offset )
For the other CRBasic dataloggers, the SDI12Recorder() instruction has the
following form:
SDI12Recorder(
Destination, SDIPort, SDIAddress, “SDICommand”,
Multiplier, Offset )