Vaisala AWS330 - Manual (Page 21)

Chapter 3 ______________________________________________________ Functional Description
VAISALA _______________________________________________________________________ 19
CHAPTER 3
FUNCTIONAL DESCRIPTION
This section describes the operating principles of AWS330.
Operating Principles
Sensors are measured by AWS330 system as:
- Voltage or resistance input converted to measurement value by analog
to digital conversion. For example, Pt100 temperature.
- Discrete pulse input converted to measurement value by counter. For
example, Rain Gauge RG13(H).
- Frequency converted to measurement value by frequency
(counter/time) measurement. For example, Anemometer WAA15
(wind speed).
- Intelligent sensors providing observation values as messages through
serial link. For example, WMT703 wind measurement.
Measurements are quality-checked against set limits to produce
observation values.
Observation values are processed further to produce statistical and
derived values.
Statistical and derived values are used to compose observation and
alarms messages.
Messages are passed through communication devices to Observation
Display or data collection system.