4-in-1 portable safety gas equipment Multi Gas monitor for O2, CH4, CO H2S

4-in-1 portable safety gas equipment  Multi Gas monitor for O2, CH4, CO H2S

1.   Application

This DSW4 model for multi gas detecting alarm is applied to underground coal mine, petrochemical industry, municipal, environmental protection and other spaces where it need to detect multi gases. This device can detect methane (ch4) or combustible gas(LEL ), oxygen (O2),carbon monoxide (CO) and hydrogen sulfide (H2S) at the same time. When the concentration of any gas in the environment is higher than the setting alarm point of concentration, this device will send out the sound and light alarm to warm users who wears it to do some protective work. This device can be hand-held to use and also can be fixed to use. It’s a type of mine explosion-proof intrinsically safe, and the explosion-proof sign is Exibdl.

2. Working principle

In this device, the methane/combustible gas sensor adopts the hot catalytic working principle and consists of black element and white element inside. The black element is the catalytic carrier of methane/combustible gas, and will occur the thermal catalytic reaction with the methane/LEL gas to change their own resistance value; the white element is a pure carrier and its resistance value is stable very much. Depending on the methane gas sensor’s characteristics, the signal is enlarged by the wheatstone bridge and displays the value in order to achieve the methane/ combustible gas concentration detection.

The CO sensor, O2 sensor and H2S sensor are all the electrochemical principles. The inside electrode will react with the being detected gases in the role of catalyst to achieve the directional movement of electron between electrodes, and make the electrical signal amplified and displayed by t amplification circuit technology and other existing technology, so that to achieve the detection of concentration.