WDDG - Water Vapour Permeability Tester

... determines the water vapor permeability of films. For evaluation you can use the analog output or the integrated data logger.

GTT to gas permeability testing
  • NEW: Intern data logger
  • Testing according to ISO 15106 - 3
  • Analog plotter output
  • Different testing clima conditions

GTT - to gas permeability testing

How it works

You can use the WDDG to determine the WVTR  (of up to 10 g/m2 d) for your specimen.
The sample is put between the top and bottom part of the permeation cell. A constant water-vapour pressure (RH) is adjusted in the upper part of the permeation cell using saturated saline or defined sulphuric acid solutions. The carrier gas (nitrogen 5.0) is pre-dried inside the WDDG. Then the carrier gas is fed into the bottom part of the permeation cell. The flow of carrier gas absorbs the water vapour that permeats through the sample and transmits it to the Keidel electrolytic cell. There the amount of water vapour is quantitatively recorded. The electronic system registers the current and displays the WVTR directly in the corresponding unit (grams of water as per square meter and day) using a 7 segment display.

The test duration depends on the WVTR of the inserted specimen. At the beginning of the test the displayed value continuously increases. You can track this increase of the WVTR with a plotter. As soon as the procedure has reached the final value (no further increase), you can stop the test.

You can adjust the sample temperature within the range of -25°C and 60°C using an external

Technical Details

WDDG Specification
Measuring Range 0.005 g/(m² d) bis 10 g/(m² d)
Resoluting within the measuring ranges 0.001 g/(m² d), 0.01 g/(m² d), 0.1g/(m² d)
Measuring ranges for the plotter output (100mV) 0.1 g/(m² d), 1 g/(m² d), 10g/(m² d)
Sample dimensions Circular, diameter 115 mm
Sample temperaturerange -25°C bis 80°C (with external water bath thermostat)
Carrier gas Nitrogen 3.5 (99,95% Vol, Dew Point -72°C), dry - ca. 100 cm³/min
Gas flow of the carrier gas Nitrogen - 40 cm³/min to max 70 cm³/min for WDDG with MEECCo elektroliecell
Secondary drying Molecular sieve 0.4 mm, pearl diameter 2 mm
Cell voltage 50 V
Dimensions 50 x 35 74 cm
Weight 30 kg
Storage temperature 0°C - 50°C
Working temperature Ambient temperature( 23°C )
Relative humidity max. 80%, non-condensing
Electrical connection WDDG 230 V / 50 - 60Hz, power consumption ca. 50 W, approx
Electrical connection for the plotter 230 V / 50 - 60Hz, power consumption ca. 50 W, approx
Electrical connection (Thermostat) 230 V / 50 - 60Hz, power consumption ca. 2300 W, approx
Standard ISO 15106 - 3

Download Datasheet