Harmful gas detector selection should pay attention to the problem

Harmful gas sensors are devices that convert the harmful gases in the air into electrical signals. The electrical signals generated by the sensors are processed, amplified and converted by electronic circuits to display and alarm the harmful gas content. It can be seen that the sensor is the basic and core component of the harmful gas detection and alarm instrument, and its quality determines the quality and function index of the harmful gas detection and alarm instrument. Sensors are used in the field and withstand the effects of various harsh environments and atmospheres. In particular, the sensors of fixed instruments have long-term continuous operation, and are also limited in explosion-proof and power supply capacity. Therefore, the requirements for harmful gas sensors are very strict.

1. Defining the purpose of the test and selecting the type of instrument In a nutshell, the detection of harmful gases serves two purposes. The first is the measurement of explosion, and the second is the detection of poison. The so-called explosion test is to detect the gas content of dangerous places and exceed the standard alarm to prevent the occurrence of explosion accidents; the detection of poisons is to detect the contents of all toxic gases in the dangerous field and exceed the standard alarm to avoid the poisoning of workers. The range of explosion detection is 0-100% LEL, and the range of poison detection is 0-several (or several hundred) ppm. There is a big difference between the two.

There are three kinds of hazardous gases in hazardous locations: first, non-toxic (or low-toxic) flammable; second, inflammable and toxic; third, flammable and toxic. The first two conditions are easy to determine, the first test explosion, the second test poison, the third case if there is a person exposed to test poison, if no personnel exposure can be measured. Select the combustible gas detection alarm device for the explosion test, and select the toxic gas detection alarm device for the poison detection. Or choose a combination of toxic and explosive detectors.

2. Defining the purpose of detection Select the type of instrument (portable or fixed) The long-term operation of the production or storage job is to use the fixed detector for leak detection; for other applications such as inspection, emergency detection, entry detection and inspection, etc., portable (or portable) instrument.

3, a clear test object, select the best instrument model. The instrument model contains three main contents of the manufacturer, function index and detection principle. The following principles should be considered when selecting the instrument model:

â—† The manufacturer speaks of good faith, good reputation, and the quality of production is guaranteed. It has passed the ISO9002 quality system certification, and has a CMC production license issued by the technical supervision department, and has the fire protection and explosion-proof certification.

â—† The selected model product function index must meet the requirements of the national standard GB12358-90, GB15322-94, GB16808-1997 and other standards.

â—† The detection principle of the instrument must adapt to the requirements of the test object and the test environment.