ROTRONIC HP23-AW-A - Manual (Page 25)

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 25 of 37
Document title
© 2009-2012; Rotronic AG E-M-HP23-V2_13
o When the device is a HygroClip 2 probe connected to a HF5 or HF8 transmitter (or similar device),
select “Probe 1” and “Probe Sel” from the menu and press ENTER. Use the UP or DOWN arrow to
select the probe to be calibrated (HF5 transmitter: be sure to select probe 1)
o Use the DOWN arrow key to select either “Temp Adjust” or “Humi Adjust” (we recommend
selecting Temp Adjust first). The following steps are the same for a temperature or a humidity
adjustment.
o Press ENTER to confirm and open the next sub-menu.
o Optional: with the “Acquired Points” menu item selected press ENTER and review the calibration
points present in memory. This submenu allows you to delete unwanted calibration points. Press
MENU when done.
o Use the DOWN arrow key to select the “Adjust” menu item and press ENTER to confirm.
o Press ENTER to activate the Adjust function. This function automatically erases the calibration points
in memory. When done adjusting, the HP23 automatically exits the menu.
5.4 Aw Mode (HP23-AW)
o This specialized mode is available only with model HP23-AW and is used for measuring the water
activity (Aw) of product samples and materials in bulk such as powders, seeds, etc.
o See technical note E-T-AW (Measuring Water Activity) for basic information on water activity and its
applications.
When set to operate in the Aw Mode, the HP23 automatically displays humidity as Aw (1.000 a
w
= 100 %RH)
and offers the following options:
• AwE measurement option
: the HP23 waits for the full equilibration of the measured product and probe.
For most products, this takes from 30 to 60 minutes. The HP23 automatically detects equilibrium conditions
(humidity and temperature) and ends the measurement at that time by freezing the display.
• AwQuick measurement option
: the HP23 uses an algorithm to accelerate the water activity
measurement and provides a result in typically 5 minutes. The measurement ends automatically and the
display is frozen. When temperature conditions are stable (both at the product and probe), the value
measured with the AwQuick mode is generally within ± 0.005 aw of the value that would be obtained by
waiting for full equilibration of the product and probe
.
5.4.1 Enabling the Aw Mode and selecting the measurement function
To set the HP23 to the water activity mode:
o Press the MENU key and select “Aw Mode”. Press ENTER to activate the Aw Mode menu.
o With the “Enable” menu item highlighted, press ENTER and use the UP or DOWN arrow key to
select ON. Press ENTER to confirm the selection.
o Use the DOWN arrow key to select the “Mode” menu item and press ENTER. Use the UP or DOWN
arrow key to select either AwQuick or AWE. Press ENTER to confirm the selection.
o The settings for either the AwQuick or AWE function can be changed after using the UP or DOWN
arrow key to highlight the setting and by pressing on ENTER. Use the UP or DOWN arrow key to
change each digit. Press ENTER to move the cursor to the right. When done, press ENTER to save
the value.
o Press MENU twice to fully exit the menu.