Thermo Scientific Omni FTIR Multi Gas CEMS Instruction Manual page 70

Calibration
Manual Background Spectrum Collection Procedure
4-6 Omni FTIR Multi Gas CEMS Instruction Manual
Select tab Bench, verify or set the following. Max. range limit: 4500, Min.
range limit: 400, Gain: 1.0, Velocity: 0.3165, Aperture: 15. Press OK.
Then go to Col Smp (Collect Sample). Set the name of the new
background in the following format:
zero air background and date (year-mm-dd) Press OK.
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