Selection of alarm

You can go to the manufacturer’s website to read the selection manual

The co detection alarm is a toxic gas detection alarm (referred to as a poison detector, an instrument that detects a toxic gas) and has the following selection methods: 1. Electrochemical toxic gas detection and alarm device - detects CO, H2S, NO, NO2, CL2, HCN, NH3, PH3 and various toxic organic compounds. 2. Photoionization toxic gas detection and alarm device - detects organic and inorganic compounds with ionization potential less than 11.7eV. 3. Infrared toxic gas detection and alarm device - detecting CO, CO2, etc. 4. Semiconductor toxic gas detection and alarm device - detecting CO, etc. When selecting: 1. Clarify the purpose of detection and select the type of instrument. In short, the detection of harmful gases has two purposes. The first is to detect explosions, and the second is to detect poisons. The so-called explosion detection is to detect the combustible gas content in dangerous places and alarm if it exceeds the standard to avoid explosion accidents. ； Toxic testing is to detect the content of toxic gases in dangerous places and alarm if it exceeds the standard to avoid poisoning of staff. The explosion detection range is 0~100% LEL, and the poison detection range is 0~tens (or hundreds) ppm. There is a big difference between the two. There are three types of harmful gases in dangerous places. First, they are non-toxic (or low-toxic) and flammable. Second, they are non-flammable and toxic. Third, they are flammable and toxic. In the first two cases, it is easy to determine whether the first test is for explosion and the second is for poison. In the third case, if someone is exposed, the poison will be measured. If no one is exposed, the explosion will be measured. For explosion detection, choose a combustible gas detection alarm device, and for poison detection, choose a toxic gas detection alarm device. 2. Clarify the detection purpose and select the type of instrument (portable or fixed). For long-term leak detection in production or storage positions, choose fixed detection alarms. ； Portable (or pocket-sized) instruments are used for other inspections, such as maintenance inspections, emergency inspections, entry inspections and patrol inspections. 3. Clarify the detection object and select the instrument model. The instrument model includes three main contents: manufacturer, functional indicators and detection principle. When selecting the instrument model, the following principles should be considered. The manufacturer is honest, has good reputation, and has guaranteed production quality. It has passed ISO9002 quality system certification, has a CMC production license issued by the technical supervision department, and has fire protection and explosion-proof certificates. ◆ The functional indicators of the selected model products must comply with the requirements of national standards GB12358-90, GB15322-94, GB16808-1997 and other standards. ◆ The detection principle of the instrument must adapt to the requirements of the detection object and detection environment. Overview of harmful gas sensors: A harmful gas sensor is a device that converts the harmful gas content in the air into an electrical signal. The electrical signal generated by the sensor is 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. Its quality determines the quality and functional indicators of the harmful gas detection and alarm instrument. Sensors are used on-site and are subject to the influence of various harsh environments and atmospheres. Especially sensors of fixed instruments have long-term continuous operation and are limited by explosion-proof and power supply capacity. Therefore, the requirements for harmful gas sensors are very strict.

List a few for reference Shanghai Yudong Electronic Technology Co., Ltd. : Portable carbon monoxide concentration indicating alarm CM-7A Beijing Yataijie Technology Co., Ltd.: PGM-1020 \CO carbon monoxide alarm Beijing Beidou Star Institute of Industrial Chemistry: H190 Pocket Carbon Monoxide Gas Alarm

It depends on whether you want it to be fixed or portable. There are many manufacturers that make this, but there are only a few well-known ones in the industry from abroad.: American MSA, German Dräger, American UTC's detronics, domestic ones: Many products such as Te'an are cheaper in China and of course the quality is better. Overall, it is more appropriate to choose the low-end imported ones.

Wuxi Greentone, Beijing Yanshan, Shenzhen Nanyou Nuoan, Shenzhen Tean, etc. are all available