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The WindSonic4 also supports the
R0C!
,
R1C!
,
M0C!
, and
MC!
commands, which are the same
as the
R!
and
M!
commands, but a cyclic redundancy check (CRC) is performed that validates
the data. Use of the checksum option is only necessary for long cable runs.
NOTE:
This section briefly describes using the SDI-12 commands. For additional SDI-12 information,
refer to
(p. 19). A complete list of SDI-12 commands supported by the
WindSonic4 is available in the Gill WindSonic manual at
www.gill.co.uk/products/anemometer/windsonic.htm
.
8.3 Long cables
Although the SDI-12 standard specifies the maximum total cable length to be 61 m (200 ft), the
WindSonic4 can have cable lengths up to 90 m (300 ft). Digital data transfer eliminates offset
errors due to cable lengths. However, digital communications can break down when cables are
too long, resulting in either no response from the sensor or corrupted readings.
9. Maintenance and
troubleshooting
NOTE:
All factory repairs and recalibrations require a returned material authorization (RMA) and
completion of the “Declaration of Hazardous Material and Decontamination” form. Refer to
the
(p. ii) page at the beginning of this manual for more information.
9.1 Troubleshooting
The WindSonic4 outputs a status code (
(p. 12)) along with each wind direction and
speed measurement. The data logger program can filter out data when the status code is not 00.
If the WindSonic4 is not powered, not connected, is using the wrong COM port/SDI-12 address,
or has missed a sample, the wind direction and speed measurement will be NaN. The program
can filter out these values and report the number of good samples that were used in computing
the online statistics. If the total number of good samples is less than 98% of the expected
samples, send the WindSonic4 to the factory for repair (see
WindSonic4 Two-Dimensional Sonic Anemometer
11