GSM-4 Four-Channel Gas Mixer

• Mix any four gasses
• Applications include control-of-breathing and hypoxia studies
• Accurate custom gas mixtures
• Wide range of gasses and flows
• Custom gas configurations at no extra cost
• Stored programs for immediate retrieval
• Stand-alone or computer controlled with supplied software

• Controlled flow range for any input gas: 10cc/min - 20 liters/min (Note 1)
• Flow accuracy (percent of full scale): +1.0%
• Flow setting repeatability: +0.15%
• Resolution: 0.1%
• Temperature coefficient: 0.05% / ^oC 
• Pressure coefficient: 0.01% / ^oC
• Response time (to 0.2%): <1 second
• Materials exposed to gas: Delrin with Viton seals
• Standard gasses for input: Air, O₂, CO₂, and N₂ (Note 2)
• Operating temperature range: 5 - 40° C
• Input gas temperature range: 0 - 50° C 
• Minimum input gas pressure: 20psi
• Maximum input gas pressure: 100psi
• Gas inlet connections: quick push/pull 1/4” OD tubing connectors
• Gas mixture outlet connection: quick push/pull 1/4” OD tubing connector
• Analog gas concentration output scaling for each channel: 0.05V / %
• Serial data format: 9600 baud, 8 data, no parity, 1 stop bit
• Electrical requirements: 120VAC/220VAC switchable, 35VA
• Dimensions: 19W x 5.25H x 12D in., 49W x 13H x 30D cm
• Weight: 20 lbs. (9kg)

Note 1: Not to be used for Human Life Support applications.
Note 2: Many other gasses can be selected, except explosive mixtures, which MAY NOT be used.

The GSM-4 Gas Mixer creates custom gas blends from any four input gasses. A mixture is defined by a Total Flow, and the percent concentration of each gas. The resulting flow for each gas is computed and displayed on the LCD display. Four user-defined mixtures can be stored locally on the GSM-4 and turned on/off with a pushbutton. Using the supplied GSM-4-CommVS software, any number of mixtures can be saved on the computer and recalled as needed. The GSM-4 can be operated solely with the front-panel controls, or controlled by the supplied software (see below). Each GSM-4 is customized with the most appropriate flow controllers for the intended application. 

GSM-4-CommVS Software

This software runs on Windows 7, 10 or later versions, and allows user-defined mixture configurations to be saved and loaded as needed. The Sequencer uses a simple programming language to perform timed protocols These timed sequences can be named, stored, and repeated as needed. This capability eliminates the need to manually switch gas mixtures for a particular experimental protocol. Each step in the sequence is programed with a TIME, and a FUNCTION selected from a drop-down menu.