ROTRONIC HP23-AW-A - Manual (Page 27)

E-M-HP23-V2_13
Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroPalm HP23-A / HP23-AW-A hand-held
indicator:
User Guide
Instruction Manual
Document Type
Page 27 of 37
Document title
© 2009-2012; Rotronic AG E-M-HP23-V2_13
5.4.3 Using the AwQuick function
The HP23 uses an algorithm to project the full equilibrium value (water activity) of the product sample:
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), the humidity data is used to project the end value of the
equilibration process (water activity). The measurement ends automatically as soon as the projected
Aw value is stable. At that time, the HP23 freezes the display.
The measurement is automatically ended and typically requires about 5 to 6 minutes.
With the default dwell time of 4 minutes, the difference between the AwQuick function and the conventional
measurement method is typically 0.005 aw or less. The value of the dwell time can be set by the user (see
SETTINGS) and is a tradeoff between speed of measurement and accuracy. Generally, a longer dwell time
produces more accurate results but causes measurements to take longer.
The value of temperature shown at the end of the measurement is the average temperature during the
measurement. The HP23 displays a trend indicator to the left of the temperature value. This is used to verify
that temperature was stable during the measurement.
1. AWQ Reset: the HP23 is ready to start measuring all connected probes
When ready to measure, press on the ENTER key.