METHOD FOR MEASURING CONCENTRATION OF COMBUSTIBLE GASES AND VAPORS IN AIR BY DIFFUSION-TYPE THERMOCATALYTIC SENSOR Russian patent published in 2017 - IPC G01N27/16 G01N25/22 

FIELD: measuring equipment.

SUBSTANCE: method for measuring the concentrations of combustible gases and vapors in the air by a diffusion-type thermocatalytic sensor includes a cyclic mode of the sensor operation with a two-stage pulse power supply with specified voltage amplitudes, duration of voltage pulses and pauses between them. Herewith the first stage of the two-stage voltage pulse is formed by short-time voltage supply to the sensor, which is 2-2.5 times higher than the nominal operating voltage of the sensor, and the duration limited by the sensor reaching the temperature is 15-20% higher than its nominal operating value. The measurement of the combustible gas concentrations is made during the transient process of cooling the sensor and is performed by measuring the difference in the output voltage signals at two strictly fixed points in time at the beginning and the end of the cooling transition process.

EFFECT: reducing the duration and power of heating and measuring the current pulse during the cyclic operation of the thermocatalytic sensor, which reduces the contact time with the reacting substances and contributes to the increase in the resistance of the catalytically active surface to poisoning by catalytic poisons and to the decrease in the blocking of this surface by carbon-coke deposits formed during oxidation of hydrocarbons and sulfur-containing combustible components.

2 cl, 4 dwg