Calibrating a nondispersive infrared gas analyzer

US5077469A · kind A · utility

Assignee

• Hartmann & Braun Aktiengesellschaft · DE

Inventors

• Walter Fabinski · Kriftel, DE
• Guenter Bernhardt · Frankfurt, DE

Key dates

• Filing date: Oct 1, 1990
• Grant date: Dec 31, 1991
• Expiry date: Oct 1, 2010

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N21/61
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Compensation and calibration method for a nondispersive infrared gas analyzer which includes an infrared source of radiation, a measuring path, a reference path, modulation devices, a detector for differential pressure measuring, comprises the following steps: first and prior to measurement, the reference gas having a variable basic concentration in the measuring component is forced through the reference branch and through the measuring branch and the detector is set to a zero position; next a dual calibration chamber is placed into the two reference paths while both of them are still passed through by the reference gas, one of the calibration chambers including a particular concentration in the measuring gas the other one lacking that measuring gas; now the sensitivity and amplification of the detector that obtains as a result of changes in the radiation on account of placing the calibration chamber into the reference and measuring path is adjusted, whereupon the calibration chamber is removed, reference gas still is passed through the reference chamber, while measuring gas now flows through the measuring chamber.