Campbell WindSonic4, Руководство по эксплуатации продукта, Страница: 16 / 35

NOTE:
To support the
Ro!
command, a CR200(X)-series or CR5000 data logger need a current
operating system. The most current data logger operating systems are available on the
Campbell Scientific website at:
www.campbellsci.com/downloads .
See SDI-12 measurement details (p. 10) for more information about this instruction.
8. Operation
This section discusses the following:
8.1 Sensor configuration 10
8.2 SDI-12 measurement details 10
8.3 Long cables 11
8.1 Sensor configuration
To mimic a mechanical anemometer, the WindSonic4 output frequency must match the data
logger scan frequency. The factory setting for the WindSonic4 is 1 Hz, which is 1 output per
second. The data output frequency of the WindSonic4 cannot be changed.
8.2 SDI-12 measurement details
The WindSonic4 typically uses an
R0!
or
R1!
command. When the data logger issues an
R0!
or
R1!
command, the WindSonic4 immediately begins transmitting the most current wind
measurements to the data logger. After receiving the R0! or R1! command, it takes the
WindSonic4 approximately 190 milliseconds ±10 milliseconds to transmit the data.
The WindSonic4 can also use an
M0!
or
M1!
command. When using an
M0!
or
M1!
command,
the data logger waits for the time specified by the sensor, sends the
D!
command, pauses its
operation, and waits until either it receives the data from the sensor or the sensor timeout
expires. If the data logger receives no response, it will send the command a total of three times,
with three retries for each attempt, or until a response is received. The
M0!
or
M1!
command will
take slightly longer to retrieve the data because of the additional handshaking required. For all
practical purposes, a data logger can measure up to four WindSonic4s at 1 Hz.
WindSonic4 Two-Dimensional Sonic Anemometer 10