Discussion on whether combustible gas detectors are universal.
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This post was last edited by shiworkstation on 2025-3-6 at 08:46. I am not from a related field, so my understanding might be incorrect; please forgive me. For catalytic combustion-type combustible gas detectors, does it not matter whether the combustible gases being detected are methane, ethanol, or n-hexane? Essentially, it is to detect the carbon content. If one molecule of substance A contains a 6-carbon atom, the lower explosion limit is a ； One molecule of substance B contains 2 carbon atoms. If the lower explosion limit b satisfies a/b < 6/2, does this mean that the probe originally used for detecting substance B can be used to detect substance A without any need to adjust its parameters? Thank you all for your responses. To summarize: when catalytic combustion-type combustible gas detectors are used to detect various substances, adjustments are needed based on the number of carbon atoms; however, using the heat of combustion for such adjustments also presents problems. It is necessary to have the supplier of the detector adjust it according to the characteristics of their product and the substances that need to be detected.
Catalytic combustion detectors primarily work by measuring the heat released when a gas burns. They exhibit a certain response to all carbon-containing combustible gases, indeed because the basic principle of detection is related to the amount of carbon. However, different combustible gases vary in their lower explosive limit (LEL) and combustion properties, which means that the sensitivity and accuracy of the same detector may also differ for different gases. For example, although both methane and acetaldehyde contain carbon, their combustion properties and the amount of oxygen required differ, which affects the detector’s response to them. Regarding the issues with Substance A and Substance B, if A has a lower LEL than B but its higher carbon content indicates that it is more explosive, in theory, the equipment originally designed for detecting Substance B needs to have its parameters adjusted in order to detect Substance A more accurately. Simply adjusting the probe from substance B to substance A without making any modifications or calibrations may result in inaccurate or unsafe detection results. In summary, although catalytic combustion detectors have a certain degree of versatility, to achieve the highest level of safety and accuracy, it is best to make appropriate adjustments and calibrations for specific gases. .
The detection principle of catalytic combustion-type combustible gas detectors is not based solely on carbon content, but rather on the heat generated when the combustible gas reacts with oxygen. The parameter settings of the probe are related to the type of combustible gas; when the type of combustible gas being detected changes, it is usually necessary to recalibrate the probe or adjust its parameters. Therefore, the compatibility of the probe cannot be simply inferred based on the number of carbon atoms.
This post was last edited by shiworkstation on 2025-3-4 16:11. Is it possible to adjust compatibility by comparing heat of combustion? For example, the heat of combustion of methane is 0.4 times that of propane, and coincidentally the LEL of propane is 0.4 times that of methane; therefore, methane detectors can detect propane without any problem.
The compatibility of catalytic combustion-type combustible gas detectors cannot be adjusted by simply comparing their heat of combustion. Although the heat of combustion is an important property of combustible gases and is related to the detection principle of the sensor (as the sensor operates based on the heat generated by the combustion of combustible gases), the response characteristics of the sensor depend not solely on the heat of combustion.