4TEV: 4TE + Volatiles Sensor

Switch sensors to measure samples with volatiles


In addition to the standard dew point sensor, the Series 4TEV has a hygroscopic polymer capacitance sensor that can be used to measure the water activity of samples containing volatiles. You can switch between sensors using the instrument menu. The capacitance sensor is less accurate (± 0.015 aw) than the dew point sensor (± 0.003 aw).

For samples containing volatiles: 4TEV and AQUALAB TDL

The Series 4TEV is best for customers who occasionally need to measure samples that contain volatile ingredients in low concentrations. If the product itself is volatile (soy sauce, alcohols, flavorings, black tea) or contains a high concentration of volatiles (flavored teas, sauces and seasonings), the laser sensor in the AQUALAB TDL is a better option.

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  • Fast: water activity readings in 5 minutes or less
  • Switch easily between volatiles and non-volatiles sensors
  • Volatiles sensor accuracy: ± 0.015 aw
  • Non-volatiles sensor accuracy: ±0.003 aw
  • Verifiable with independent salt standards
  • Repeatable: different users, different locations, same result
  • Portable: the meter weighs just 7 pounds
  • Easy to use: precise measurements with minimal training
  • Secure: offers administrative control over calibration and sample data


Sensor types

Dewpoint, Capacitance

Volatiles sensor accuracy

± 0.015 aw

Dewpoint sensor accuracy

±0.003 aw

Water Activity Accuracy

±0.005 @ 25 ◦C

Water Activity Resolution

0.0001 aw

Water Activity Range

0.000 − 1.000 aw

Water Activity Repeatability

0.001 aw

Read Time*

5 min

Temperature Control

25 ◦C Standard; 15 to 50 ◦C (with calibration)

Temperature Adjustment Increment


Sample Temperature Accuracy*

±0.2 ◦C

Sample Temperature Resolution

0.01 ◦C

Temperature Stability

User-Selectable Range, Internal Thermoelectric Controlled

Sample Dish Capacity

7.5 ml Recommended (15 ml Full)

Measurement Time

Average of 5 minutes

Program Identification

Alphanumeric, Programmable to Display Product Name, Lot, or Product ID Number

Data Storage

8,000 Readings

Data Communications



128 x 64 Pixel Graphical Display with Backlighting

Case Dimensions

26.7 x 17.8 x 12.7 cm

Case Material

Machined Aluminum Frame; Lustran 433 (ABS) with Fire Retardant


3.1 Kg (6.83 lbs.); Instrument only: 6.55lb = 2.97 kg


110 to 220 VAC, 50/60 Hz Warranty: One year parts and labor

Operating Environment

4 to 50 ◦C; 90% Relative Humidity (Non Condensing)Operating Environment: 4 to 50 ◦C; 90% Relative Humidity (Non Condensing)



UL Listed


One Year Parts and Labor

*AquaLab TDL is calibrated to a NIST traceable temperature standard.



Have a question or problem? Our support team can help.

We manufacture, test, calibrate, and repair every instrument in house. Our scientists and technicians use the instruments every day in our product testing lab. No matter what your question is, we have someone who can help you answer it.


Phone: 509-332-5601