Application of gas detector sensor

How a gas detector works.

Gas detection systems are safety technology products, best used to protect workers' lives and ensure factory safety. Gas detection systems are designed to sense the concentration of hazardous gas vapors, trigger alarms and beam light signals -- and initiate responses before hazardous situations arise for employees, assets and the environment. They are an important tool in determining whether hazardous gas levels have been reached and the source of leaks in the surrounding environment. A variety of gas detector sensors are available for domestic, commercial and industrial uses. The goal here is to master the principle and application of gas detectors to play to our strengths.

Gas detectors use sensors to measure the concentration of various gases in the atmosphere. Sensors are used as reference points and scales that produce a measurable current when a chemical reaction caused by a particular gas occurs. Sensors will monitor these currents and alert users immediately if the gas approaches harmful levels.
Gas detection technology

The gas detector classifies the detected gas as combustible or toxic. Within this broad category, they are further defined by the technologies they use: catalytic and infrared sensors detect combustible gases, while electrochemical and metal oxide semiconductor technologies typically detect toxic gases.

Combustible gas detection

Catalytic sensor: This technology is used to detect combustible gases such as hydrocarbons, and it uses the science of catalytic oxidation. The sensor of this detector is mainly designed by platinum treated coil. When the combustible gas comes into contact with the catalytic surface area, it is oxidized and the wiring resistance changes due to the heat released. Bridge circuits are often used to indicate resistance changes.

Infrared sensors: These sensors are also called infrared detectors. Infrared sensors detect combustible gases, particularly hydrocarbon vapors, through a system of transmitters and receivers. Usually, the transmitter is the light source and the receiver is the light detector. If there is gas in the optical path, it will interfere with the optical transmission power between the transmitter and the receiver. The altered state of the light determines whether and what type of gas is present. They can determine the presence of a gas and specify the type of gas.

Infrared sensors use light-emitting transmitters and receivers to sense when gas is present. It interferes with light transmission and emits an alarm.

Toxic gas detection

Electrochemical sensors or batteries: These are most commonly used to detect toxic gases such as carbon monoxide (CO 2), chlorine (Cl 2), and nitrogen oxides (NO x). When gas is sensed, they act through signals from the electrodes. This process is achieved by allowing the gas to diffuse through the porous membrane to the electrode to be oxidized or reduced. Typically, these types of detectors are very sensitive and send a warning signal through an electric current. Various manufacturers make these detectors with digital displays. Electrochemical gas detectors are used in various environments, such as oil refineries, gas turbines, chemical plants, underground gas storage facilities, etc.

Metal oxide semiconductors (MOS) : They are also used to detect toxic gases (usually carbon monoxide). The technology works in conjunction with a gas-sensitive film consisting of tin oxide or tungsten oxide, using a chemical reaction that occurs when the gas comes into direct contact with the sensor. The sensitive film reacts with the gas, triggering the device when it reaches toxic levels. In general, metal oxide sensors are considered efficient because of their ability to operate in low humidity ranges. In addition, they can detect a range of gases, including combustibles.

However, there are other high-tech detection devices, such as holographic gas sensors, ultrasonic gas leakage detectors, photoionization detectors and so on. Calibration should be performed periodically as a safety procedure to ensure that the detector measures the correct gas level.

In addition, the service life of gas detectors usually depends on the amount of gas steam to which they are exposed. JXCT has the full procurement, supply and maintenance capabilities of gas detectors.