Introduction to the principle of operation of a combustible gas detector
The combustible gas detector is one type of gas detector, but its working principle is somewhat different from that of the gas detector. Before using the instrument, we should first understand its working principle, so that we can use it better in subsequent work. Let me introduce to you the working principle of the combustible gas detector.
How does a combustible gas detector work?
1. The principle of the catalytic combustible gas detector is to measure the combustible gas through the resistance change produced by heating the refractory metal platinum wire. When combustible gas in the environment enters the detector, an oxidation reaction (flameless combustion) will occur on the surface of the platinum wire. The heat generated in this process will increase the temperature of the platinum wire, causing the resistivity of the platinum wire to change. Therefore, when When the combustible gas detector encounters high temperature and other factors during use, causing the temperature of the platinum wire to change, the resistivity of the platinum wire will also change, and the measured data will also have certain differences.
2. The principle of semiconductor combustible gas detector is to use the resistance change on the semiconductor surface to measure the concentration of combustible gas. The semiconductor combustible gas detector uses highly sensitive gas-sensitive semiconductor components. When it is in working condition, if it encounters combustible gas , the semiconductor resistance will drop, and the drop value corresponds to the combustible gas concentration.
3. The structure of the combustible gas detector is mainly composed of two parts: detection and detection. The principle adopted in the structure of the detection part is that the sensor uses a detection element, a fixed resistor and a zero-adjusting potentiometer to form a detection bridge. The bridge uses platinum wire as a carrier catalytic element. After the instrument is started, the temperature of the platinum wire rises to the operating temperature, and the combustible gas in the air will reach the surface of the element through natural diffusion or other methods.
Combustible gas detector types
1. Portable combustible gas detector:
It generally uses natural diffusion to detect flammable gases, and the sensor used in the detector also has high sensitivity. In addition, most combustible gas detectors also use embedded micro-control technology, which makes the instrument simple to operate and has multiple functions. It can also improve the work efficiency and accuracy of the detector to a certain extent.
2. Pump-suction combustible gas detector:
Its detection principle is to use a built-in suction pump, which can quickly measure the concentration of combustible gases in the working environment. Moreover, the pump-type combustible gas detector uses a catalytic combustion sensor, and also has a real-time screen display of measurement data and accurate audible and visual alarm prompts, which provides guarantee for workers to successfully detect gas in unfavorable working environments while ensuring personal safety. .
3. Online combustible gas detector:
The structure of the online combustible gas detector is composed of an alarm and a combustible gas detector. Generally, we place the gas detection alarm in the duty room, while the fixed combustible gas detector is installed in a location where gas is prone to leakage. , when the gas concentration exceeds the normal range, the instrument will automatically send out an alarm signal and start equipment such as solenoid valves and exhaust fans to automatically eliminate hidden dangers.
