Taking A Reading; Measurement Steps; How Aqualab Takes Readings - Decagon Devices AquaLab 4TE Operator's Manual

AquaLab

9. Taking a Reading

9. Taking a Reading

Measurement Steps

Once you have verifi ed for cleanliness, calibration and prepared
your sample, you are ready to take readings. Th e process is simple:
• Move the chamber lever to the Open position and lift the cham-
ber lid.
• Check the top lip and outside of the sample cup to make sure
they are free from sample residue and that sample cup isn't over-
filled. (remember, an over-filled sample cup may contaminate
the chamber's sensors).
• Place your prepared sample cup in the chamber. The sample cup
lid must be removed while in the testing chamber for correct
functionality.
• Close the chamber lid and move the lever to the Read position.
This will seal the chamber and start the reading.
In 1 to 2 minutes, the fi rst water activity measurement will be dis-
played on the LCD (this is an intermediate reading and not the
fi nal water activity). Length of read times may vary depending on
temperature diff erences between the chamber and your sample, and
other properties of your sample.

How AquaLab Takes Readings

AquaLab's reading cycle continues until the rate of change of three
consecutive readings are less than 0.0005 a
strument crosses the dew threshold numerous times to ensure equi-
of each other. Th e in-
w
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