HEAT CONDUCTION TYPE GAS CONCENTRATION MEASURING INSTRUMENT

To provide technology capable of determining whether or not water is attached to a gas detection element.SOLUTION: A heat conduction type gas concentration measuring instrument comprises: a measurement chamber into which a gas whose concentration is to be measured is taken; a temperature detection element that is installed in the measurement chamber and detects the temperature of the gas; a gas detection element that is installed in the measurement chamber and detects the concentration of the gas; a control unit that controls the amounts of currents respectively flowing through the temperature detection element and the gas detection element so that a temperature difference between the temperature detection element and the gas detection element is kept at a predetermined value; a measurement unit that measures the concentration of the gas according to the current amounts; and a determination unit that determines whether or not water is attached to the gas detection element, according to the magnitude of overshoot of an output of the gas detection element at the start of energization of the control unit.SELECTED DRAWING: Figure 7 【課題】ガス検出素子に水が付着したか否かを判定できる技術を提供する。【解決手段】熱伝導式ガス濃度計測装置は、濃度の計測対象であるガスが取り込まれる計測室と、計測室に設けられ、ガスの温度を検知する温度検知素子と、計測室に設けられ、ガスの濃度を検出するガス検出素子と、温度検知素子とガス検出素子との温度差を予め定められた値に保つように、温度検知素子とガス検出素子とに流れる電流量を制御する制御部と、電流量に応じてガスの濃度を計測する計測部と、制御部への通電開始時におけるガス検出素子の出力のオーバーシュートの大きさに応じて、ガス検出素子に水が付着しているか否かを判定する判定部と、を備える。【選択図】図７