Section 6 Parameter Settings
81 FT722 & FT742 (RS485) – FF & PM Sensors – User Manual
6.4.24 UC.1: Set or Query General User Calibration Settings
$<listenerID>,UC<table>*<checksum><cr><lf>
$aa,UCx*hh<cr><lf>
$<listenerID>,UC?*<checksum><cr><lf>
$aa,UC?*hh<cr><lf>
$<talkerID>,UC=<entries>,<table>,<UCRAMChecksum
>, <UCFlashChecksum>*<checksum><cr><lf>
$aa,UC=nn,x,yyyy,zzzz*hh<cr><lf>
User Calibration Table enabled
User Calibration Table disabled (Factory Default Setting)
Number of calibrated table entries
User calibration table RAM copy checksum
Saved user calibration table Flash copy checksum
Example 1
Enable the user calibration table and verify new setting
Query user calibration table status
$WI,UC=55,E,5174,5174*70<cr><lf>
Use the UC command to enable or disable the implementation of the user calibration table
for calibrating wind speed readings.
The four-digit user calibration table checksum is calculated by summing all table entries
over the number of table rows present. The least significant 4 digits of the resulting sum
are retained as the table checksum. The user-defined text string is not included in the
checksum. Each xx.xx speed value is treated as an integer by ignoring the decimal point.
For example, the table row:
15.00, 14.97 is summed as 1500 + 1497 = 2997. A table sum of 55174 results in the
checksum 5174.
If the user calibration table has not been loaded, the number of calibrated table entries
(nn) will be 00 and the saved user calibration table Flash copy checksum (zzzz) will be
5535.
Contact FT technologies for details on simplified methods to change User Calibration
Table settings.
When the User Calibration facility is
enabled, the uncorrected wind speed
indication of the sensor is calibrated
according to the stored calibration
records, using linear interpolation.