Cleaning; Cleaning Lenses And Hoods - Vaisala PWD22 User Manual

User's Guide _______________________________________________________________________
90____________________________________________________________________ M210543EN-B
Open the communication line by typing the following:
OPEN
PWD22 answers as follows:
LINE OPENED FOR THE OPERATOR
The line can be released to automatic messages using the CLOSE
command. For details, see Chapter 5, Operation on page 55.

Cleaning

It is very important to clean PWD22. No specific operations are
necessary before cleaning the sensor, in other words, it is possible to
use the service terminal while cleaning. Some erroneous data may,
however, be generated. Problems from this can often be eliminated by
restarting PWD22 after cleaning (by pressing power OFF/ON, for
example).

Cleaning Lenses and Hoods

The lenses of the PWD22 transmitter and receiver units should be
relatively clean to get reliable results as dirty lenses give too good
visibility values. Cleaning should be done every six months or more
often depending on the conditions (for example, if there are roads
nearby).
Use the STA command for monitoring the system performance.
Usually a data message announces, if there are some warnings.
Cleaning should be done after the warning the following warning:
BACKSCATTER INCREASED
The complete cleaning procedure is as follows:
1. Moisten a soft, lint-free cloth with isopropyl alcohol and wipe
the lenses. Be careful not to scratch the lens surfaces. Lenses
should dry indicating that the lens heating is functioning.
2. Check that the hoods and lenses are free of condensed water, or
ice and snow deposits.
3. Wipe the dust from the inner and outer surfaces of the hoods.
.