Gravimetric Water Vapor Sorption Analyzer, V-GA-1,United States InstruQuest price supplier

The VGA-1 is is the smallest size version of the Versatile Water Vapor Sorption Analyzers. The purpose of the instrument is to provide water vapor sorption isotherm for larger size sample which exhibits rather non-zero water uptake characteristics. The cost of the instrument is few times smaller then other high-end gravimetric sorption analyzers. Since special permation cells can be used, the mass loss through a studied membrane (fiilm) at the controlled conditions of temperature and relative humidity can be obtained.

Other design objectives were to utilize a modular approach. The RH generator module provides the controlled RH stream to the flow type gravimetric analyzer, but if not uset for this purpose, it can be utilized to interface with other equipment and a separate software package is provided. Instead of the previously used V-gen Model 2 Dew Point Generator, the HumiSys LF RH Generator is currently used with this system.

The other main module is the V-GA isothermal chamber, which houses a semi-microbalance on top and where the sample chamber is located. The Peltier based Cooling allow for ambient and subambient temperature measurements. The upper temperature omeasuremetns is 60 C although for loss on dry conditions, 80 C or so temperature can be used. A proprietary design of anti-condensation feature is implemented to avoid moisture condensation at the balance measurement port.

Any desktop or laptop compuyter with Windows operating system can be used for automatic control. The operation software works on any 32 or 64-bit Windows system. Experimental data of mass uptake versus time at diferent RH levels are obtained.