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<< Click to Display Table of Contents >> Navigation: Software > HygroSoft > Main features > Water activity > AW measurement modes |
Hygrosoft supports two modes for measuring water activity, the AwE- and AwQuick-function.
AwE mode
In this mode, Hygrosoft monitors the stability of both temperature and humidity. The measurement is automatically ended as soon as both humidity and temperature reach equilibrium. The natural (or static) equilibration of most products typically requires from 45 to 60 minutes and can take as long as a couple of hours.
In the AwQuick mode, Hygrosoft uses an algorithm to project the full equilibrium value (water activity) of the measured product. The measurement is automatically ended and typically requires about 5 minutes.
Hygrosoft performs the following tasks:
1)The value of the humidity signal is constantly monitored
2)The stability of the temperature signal is constantly monitored
3)After an initial period of time (dwell time), Hygrosoft uses the humidity data to project the end value of the equilibration process (water activity). The measurement ends automatically as soon as the projected Aw value is stable.
With the dwell time set to 4 minutes, measurements typically require about 5 minutes. When temperature conditions are stable (both at the product and probe), the measurement obtained with the AwQuick mode is generally within ± 0.005 aw of the measurement that would be obtained by waiting for full equilibration (AwE mode).