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VAISALA _________________________________________________________________________ 1
Table of Contents
CHAPTER 1
GENERAL INFORMATION............................................................................ 7
About This Manual ................................................................... 7
Contents of This Manual ....................................................... 7
Version Information............................................................... 8
Related Manuals ................................................................... 8
Feedback .............................................................................. 8
Safety ........................................................................................ 9
General Safety Considerations ............................................. 9
Product Related Safety Precautions..................................... 9
ESD Protection ................................................................... 11
Trademarks............................................................................. 11
License Agreement ................................................................ 11
Warranty.................................................................................. 11
CHAPTER 2
PRODUCT OVERVIEW ............................................................................... 13
Introduction to Vaisala Present Weather Detector PWD22 13
Hardware Structure................................................................ 14
Sensing Element in PWD22 ............................................... 14
PWT11 Transmitter........................................................ 14
PWC22 Controller/Receiver........................................... 15
Vaisala RAINCAP
®
Rain Sensor ................................... 15
Temperature Sensor (TS).............................................. 15
Power Supply................................................................. 15
Operating Principle ............................................................. 15
Using PWD22 ..................................................................... 17
Product Nomenclature .......................................................... 18
CHAPTER 3
FUNCTIONAL DESCRIPTION..................................................................... 19
Optical Measurements........................................................... 20
Optical Arrangement ........................................................... 20
Transmitter Unit PWT11 ..................................................... 20
Light Receiver ..................................................................... 21
Additional Measurements ..................................................... 21
Vaisala RAINCAP
®
Rain Sensor......................................... 21
Background Luminance Sensor PWL111 (optional)........... 22
BLSC Command ............................................................ 23
Continuous Mode...................................................... 23
Day/night switch Mode ............................................. 23
Disabling PWL111 .................................................... 23
BLCAL Command.......................................................... 23