There are many kinds of gas transmitters, and the common ones in the market are as follows:
Optical gas transmitter is based on optical principle for gas measurement. It mainly includes infrared absorption type, spectral absorption type, fluorescence type, optical fiber chemical material type, chemiluminescence type, optical fiber fluorescence type and optical fiber waveguide type.
1. The infrared gas transmitter is the main type of optical gas transmitter. Because the infrared absorption peaks of different gases are different, the gas can be detected by measuring and analyzing the infrared absorption peaks. There are three types of analyzers: fluid switching infrared analyzer, direct determination infrared analyzer, and Fourier transform on-line infrared analyzer, which have the ability of anti vibration and anti pollution. Combined with computer, they can continuously test and analyze gas, and has the functions of automatic correction and operation.
2. Compared with other types of gas transmitter, such as electrochemical type, catalytic combustion type and semiconductor type, infrared gas transmitter has a series of advantages, such as wide application, long service life, high sensitivity, good stability, high cost performance, low maintenance cost, online analysis, and it is suitable for many gases, widely used in petrochemical industry, metallurgical industry, industrial mining, and the fields of air pollution detection, agriculture, medical and health.
The electrical gas transmitter is that the electrical parameters of materials will change with gas concentration. Electrical gas transmitters can be divided into resistance type and non resistance type. Resistance type gas transmitters mainly include contact combustion type, thermal conductivity type and semiconductor gas transmitter. Non resistive gas transmitters usually use the current or voltage of the material to change with the gas content.