The multi gas sensor system OCS uses different types of metal oxide gas sensors in temperature cycled operation, thus significantly improving the sensitivity and selectivity of the sensors. The sensors are very broadband sensors, i.e., they respond to a variety of gases, including hydrogen. The complete gas emission produced by the sample is detected integrally. As a result of the temperature cycled operation, temperature-depending gas reactions and dynamic effects due to temperature changes can be used for increasing the information content.
In addition, temperature, humidity, and pressure of the sample gas are measured.
In the measurement phase, the sample is put into an external testchamber, which can be adapted to the dimensions of the sample depending on the application. A standard glass test chamber for small samples is available.
By means of integrated fluidics, the OCS controls the complete measurement process, consisting of:
• Flushing of the test chamber with synthetic air or zero air to remove ambient air from the test chamber
• Accumulation phase for increasing the measured concentrations
• Transport of the test chamber atmosphere to the sensor and detection of the gas mixture
• Post flushing to clean the equipment of sample emissions