Clean; Zero - Vaisala PWD22/52 User Manual

Chapter 5 ________________________________________________________________ Operation
NOTE
VAISALA _______________________________________________________________________ 75
The calibrator signal value is printed on the labels of the glass plates.
Typically the signal is close to 500 Hz. PWD22/52 calculates a new
scaling factor and stores it in the non-volatile memory (EEPROM).
If the PWC22/52 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 PWD22/52 output is the following:
CLEAN REFERENCES
TRANSMITTER 12.0
RECEIVER 1402
UPDATED
>

ZERO

The ZERO command has no parameters and it is used in calibrating
visibility to display the zero signal status.
When the signal blocker of the PWA11 calibrator kit is installed to the
lens hood of the receiver (box), the PWD22/52 software checks for the
very low signal and low noise. If the signal or noise is out of the internal
check limits, an error message is shown.
Give the following command:
>ZERO
The output is the following:
ZERO SIGNAL: OK
>