GSM-3 Gas Mixer

Presentation

The GSM-3 Gas Mixer is a versatile and accurate device for creating custom respiratory gas mixtures. Any three gasses can be connected as inputs, and the output is the userprogrammed mixture of these gasses. The instrument can operate in a stand-alone mode, with mixture programming done from the front panel controls, or it can be controlled using an attached computer running the supplied software.Besides the mixing function, the GSM-3 can operate as an accurate flow source for a single gas.

Operating principle

The mixer uses thermal mass flow controllers to provide any programmed mixture in the range of 0 - 10 lpm for each gas with a resolution of 0.1% concentration. Front panel controls are used to set the total desired total output flow, as well as the concentration of each of the three component gasses. The LCD display shows the set concentrations, as well as the computed flow rates for each gas.

Up to four custom mixtures can be created and stored in non-volatile memory for future use. Any of these stored mixtures can be immediately selected and executed. This function allows rapid step-changes in concentrations to be performed with the push of a button.

The flow controllers are pre-calibrated for the three most commonly used respiratory gasses: O2, CO2, and N2. Other gasses can also be selected, and internal correction factors are automatically applied to compensate the flow controllers for differing gas densities.
Besides operation as a stand-alone gas mixer, the GSM-3 can also be programmed and operated from an attached computer using a serial port. A WindowsTM software application is provided with the instrument. This software allows convenient setting up and storage of any gas mixtures. In addition, it allows timed protocols to be set up and executed. For example, a program could be created that periodically changes the gas mixture from room air O2 concentrations to hypoxic values over a set period of time. Any Windows-based PC with an available serial port can be used. The GSM-3 Gas Mixer comes ready to use with CD-ROM software and a serial cable. Up to three input gasses can be attached, with a minimum pressure requirement of 20psi.

Standard features

• Accurate custom gas mixtures
• 0 - 10 lpm for each of three gasses
• Stored programs for immediate retrieval
• Stand-alone or computer controlled
• Software allows timed protocols

Applications

• Gas mixtures for in vivo or in vitro studies
• Control of breathing studies
• Environmental chambers
• Gas analyzer calibration mixtures
• Hypoxia and sleep studies