Example of the wa command message – Vaisala WS425FG User Manual
Page 44
User's Guide ______________________________________________________________________
42 ______________________________________________________________________________
The sensor response to the WA command consists of the averaged wind
speed and direction data, peak wind speed, and associated direction.
The average wind speed is a scalar running average of the fundamental
one second interval wind speed measurement made by the sensor. The
average direction is a unit vector running average over the same run
length set with the WJ command. The peak wind speed is the largest
scalar running average wind speed during the number of seconds before
the command set by the WJ command for average wind. The peak wind
run interval is also set in the WJ command. The peak wind direction is
the running unit vector average direction calculated at the same time the
peak speed was found.
The command also indicates the sensor status, the averaging time for
average and peak wind speed and wind direction and signal quality,
which shall be a numeric value from 0 to 99 representing the data
quality of processed data samples during the averaging interval. For
example, a value of 99 would signify that all data samples were
determined to be valid and were processed during the averaging
interval. If some samples were determined to be "missing", these
samples would not be processed and the reported signal quality would
be a proportional value less than 99.
Example of the WA Command Message
The following is an example of the message from the wind sensor for
the WA command:
WAP2131870503012.6014.7K99xx
Table 4
Explanation of the WA Command Message
Byte
Description
Value
1
Start of text
STX
2
Sensor ID
W
3
Command identifier
A
4
Sensor status (notes b, c)
P/F/H
5-7
Averaged wind direction (degrees)
213
8-10
Wind direction (degrees) @ peak wind speed
187
11-12
Averaging time for wind speed and direction
(seconds)
05
13-14
Averaging time for peak wind speed and
direction (seconds)
03
15-19
Averaged wind speed
012.6
20-24
Peak wind speed since last WA command
014.7
25
Wind speed units (knots)
K