Finding the Right Water Activity Meter for Your Application

Some Considerations:

Accuracy
Government regulations (or your own product development specifications) may require your product to be within a certain water activity zone. If this zone is narrower than ±0.015 a_w, you will need either the Series 3 or the Series 3TE.

Temperature Control
Water activity is temperature sensitive. The Series 3TE has internal temperature control. This is useful for:

Studying effects of temperature on sample water activity.
Government or company regulations on temperature-specific water activity measurement.
R&D (accelerated shelf-life studies, etc.)
Isotherm studies.
When the ambient temperature is unstable.

This table compares the features of the AquaLab models and the DA7200.

Features	Series 3TE	Series 3	DA7200
Sensor Type	Chilled Mirror Dew Point	Chilled Mirror Dew Point	NIR
Accuracy	± 0.003 a_w	± 0.003 a_w	± 0.02 a_w
Repeatability	± 0.001 a_w	± 0.001 a_w	—
Resolution	± 0.001 a_w	± 0.001 a_w	± 0.001 a_w
Range	0.03 to 1.000 a_w	0.03 to 1.000 a_w	0.10 to 1.000 a_w
Measurement Time	< 5 minutes	< 5 minutes	6 seconds
Temperature Control	Internal 15-50°C ±0.2°C	None	—
Warranty	3 yrs parts & labor	3 yrs parts & labor	1 yr parts & labor
Summary	Highest accuracy and fast read times. Built-in temp. control.	Highest accuracy and fast read times.	Instant readings, no sample preparation.