Vapour Sorption Analyser

Moisture release curves are your job. Spending countless hours in the lab shouldn't be.

Characterizing soil beyond basic measurements is complicated. Yes, you can assemble a series of complex devices on your own to help understand soil behavior better.  But even with a dedicated graduate student at your disposal, the process will still prove difficult. What you need is an automated instrument.

VSA also stands for very simple and highly accurate

If you want to know something about your soil-how it behaves, how much clay there is, or if there are crystalline structures that may expand when water is present, the VAPOR SORPTION ANALYZER (VSA) is your simplest and most accurate option. It automates the entire process of moisture release curve construction in the dry region (-10 to -475 MPa) by accurately measuring simultaneously, at regular intervals, the water potential and the moisture content of a sample. The result is relief from a time-consuming, expensive and complicated process.

Set up a test, and walk away

With the VSA, it takes about five minutes to set up a test. Simply tell the instrument the humidity levels and times you'd like to use, put the sample into the instrument, and move on to other tasks. The data from your test are automatically recorded and sent to your computer. In just 24 to 48 hours, the VSA generates curves with up to 200 data points (water potential vs. water content) for both adsorption and desorption. Powerful automation adds up to powerful time savings.

Delve deeper into your dry soil analysis

The VSA enables you to study the soil at a particle level, examining its chemical makeup and how the layers of soil imbibe water as it gets wetter or lose water as it gets drier. It's the first instrument to generate both Dynamic Dew Point Isotherm (DDI) and Dynamic Vapor Sorption (DVS) moisture release curves. This means the VSA continuously wets the sample and stops periodically to measure how heavy it is (DDI), or it keeps the sample at a constant humidity, recording how long it takes for the sample to come to equilibrium (DVS).

With so much automation at your fingertips (including both drying and wetting), making moisture release curves can now officially be considered convenient.

Soil moisture release curves-simplified

Simple. Automated. Precise. The VSA saves you time and frustration by eliminating the complexity of custom techniques and automatically generating soil moisture release curves in the dry range. Powerful 'click and read' efficiency makes it easier than ever to draw accurate conclusions about your soil's behavior, its expansibility, its makeup and its performance as an engineering material.

Feature Specification
Water Potential Range
-10 to -475 MPa
Accuracy ±1 MPa, or ± 1%
Isotherm Methods Dynamic Dewpoint Isotherm (DDI) & Static (DVS)
External Gas Not needed, if external gas no more than 7PSI.
Computer Interface USB
Mass Resolution ±0.1 mg
Water Reservoir 20ml
Sample Cup Volume 10cc
Sample Weight 500 to 5,000mg
Power 110 V to 220 V AC, 50/60 Hz
Weight 28 lbs
Temperature 15°C to 60 °C (sample chamber temperature; sample temperature is measured separately, and may vary)
Temp Stability ±0.1 °C
Dimensions W 10" x L 15" x H 12" , 25.4cm x 38.1cm x 30.5cm

We periodically send an email newsletter containing updates, new product releases, training and advice. If you would like to receive these please subscribe below.


Labcell Limited exclusively supply and support METER products in the UK & Ireland.

Non UK/Ireland Customers, please contact METER Environment at:www.metergroup.com/environment/



  • Fast, expansive soil characterization
  • Automatic static and dynamic soil water characteristic curves
  • Click and read efficiency
  • Generates curves with up to 200 data points for both adsorption and desorption
  • Works in the dry soil range (-10 to -475 MPa)
  • Set up a test in five minutes
  • Hold humidity constant with the new static feature

VSA Quick-start Guide
Size: 1.3 MB (1,340,765 bytes)

Quotation Request

Email us to request a quotation for the Vapour Sorption Analyser