Cal; Clean - Vaisala PWD22 User Manual

User's Guide _______________________________________________________________________
NOTE
84____________________________________________________________________ M210543EN-B

CAL

The CAL command is used to calibrate the visibility measurement.
The calibration is done by using opaque glass plates with known
scatter properties. The plates belong to the PWA11 calibrator kit.
The command is the following:
CAL Calibrator_signal_value
For example:
>CAL 485
The calibrator signal value is printed on the labels of the glass plates.
Typically the signal is close to 500 Hz. PWD22 calculates a new
scaling factor and stores it in the non-volatile memory (EEPROM).
If the PWC22 board has been changed and the status message shows
the VISIBILITY NOT CALIBRATED error, use FCAL instead of
CAL to make a factory-like calibration.

CLEAN

The CLEAN command has no parameters and it is used to set the
clean references for contamination control. This command is given
during maintenance procedures after cleaning of the lenses or after
replacement of the transmitter or receiver electronics.
Give the following command:
>CLEAN
The PWD22 output is the following:
CLEAN REFERENCES
TRANSMITTER 12.0
RECEIVER 1402
UPDATED
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