Response time of gas detectors
The response time shows how quickly the gas sensor reacts to a detected gas. In theory, the quicker the response, the better; that is, the device's resistance value should change to its predetermined resistance value as soon as the gas sensor makes contact with the gas being measured or the gas concentration changes. But in reality, it always takes some time to settle on a value. The response time tres is the amount of time after the element comes into contact with the gas to be measured for the resistance to reach 90% of the stable resistance value at this concentration. It is often represented as tres and is defined as the response time.
Recovery time for gas detectors
In contrast to the reaction time, the recovery time, sometimes referred to as the desorption time, shows how quickly the gas sensor desorbs the detected gas. Again, I'm hoping for a quick arrival this time. The recovery time trec is the amount of time needed to extract the element from the detecting gas until the resistance value recovers to 10% of that of regular air. It is denoted by the symbol trec and is defined as the recovery time.
categorization of gas sensors
Generally made up of a sensitive element and a conversion element, a sensor is a device or gadget that may be measured and converted into an useful output signal in accordance with a given law. The term "sensitive element" refers to the portion of the sensor that can feel or react to the measured directly, while the term "conversion element" refers to the portion of the sensor that can transform the measured into an electrical signal that can be transmitted or measured.
The most common types of gas sensors are semiconductor sensors (both resistance and non-resistance types), insulator sensors (contact combustion type and capacitive type), electrochemical type (potentiostatic electrolysis type, galvanic battery type), infrared absorption type, quartz oscillation type, fiber type, thermal conductivity type, surface acoustic wave type, gas chromatography type, etc.
with no drift
When a gas detector is used for a while or put to use in a new environment, zero drift refers to the occurrence where the indication value of the detector in clean air or in an environment without such gas is greater than (positive drift) or less than zero (negative drift).
