What is the core component of a gas detector?
Gas detector is one of the most commonly used detection instruments in industrial production, can detect the concentration of toxic and hazardous substances for us to work, the use of gas detectors can detect the presence of gas species in the environment, according to the results of its detection using the appropriate safety and protective equipment. So you know what the core components of the gas detector?
The core components of the gas detector:
The core component of the gas detector is the gas sensor, which can detect the concentration of gas and temperature and humidity parameters, and convert the gas concentration signal into an electrical signal. Then the concentration information will be displayed through the display device. Gas detector in addition to the sensor and detection of the main board, power supply devices, alarm devices, sampling devices, display devices, etc., each part is very important, indispensable.
Gas sensor as the core component of the gas detector, according to the type of gas to be measured, the detection accuracy and measurement range, the sensor detection principle is different, the market is more common catalytic combustion gas sensor, electrochemical gas sensor, thermal conductivity gas sensor, infrared gas sensors, PID light ionization sensor and other types of sensors.
The most commonly used sensor for detecting combustible gases is the catalytic combustion type, which is characterized by good output signal linearity, low price and no cross-interference with other gases. Based on the Wheatstone bridge principle, the gas to be measured can be flamelessly burned with the sensing resistor, and the high temperature makes the resistance of the sensing resistor change, breaking the balance of the bridge, thus outputting a stable current signal.
Detection of toxic gases is commonly used sensors for electrochemical type, which has the advantages of stable performance, low power consumption, good accuracy, not contaminated by other gases, etc., can detect most of the toxic and hazardous gases. This type of sensor can react with the measured gas and produce an electrical signal proportional to the gas concentration.
Infrared type gas sensor is to utilize the selective absorption nature of different gases to the near infrared spectrum, the relationship between gas concentration and absorption intensity to determine the gas concentration, with a long life, higher sensitivity, better stability, easy maintenance and a series of advantages.
PID photo ionization gas sensor is through the UV light source will gas ionization into positive and negative ions can be detected by the detector, and then will be detected charge into the current signal, the current is amplified and through the corresponding algorithm is converted into the concentration value of the gas. The accuracy of this gas sensor is very high, can be detected to ppb level, good stability, no damage to the gas, fast response time, in the detection of VOC volatile organic compounds used more, but its price is also relatively high.
