Four notices in the application of explosion proof infrared cameras
In the field of security CCTV cameras, there is a kind of widely used camera named explosion-proof infrared cameras. Night vision explosion-proof cameras are usually called explosion-proof infrared cameras, or explosion-proof white light cameras, with excellent monitoring effect at night. Explosion-proof infrared camera has a long distance of night vision, concealment, stable performance and other outstanding advantages, and thus occupies most of the market in the explosion-proof probe monitoring. An excellent night vision performance is also shown, the following points need to be noted in the application:
First, the working conditions of infrared lamps
Generally speaking, the radiant power of the infrared lamp of the explosion-proof infrared camera is proportional to the forward working current, but when it is close to the maximum rated value of the forward current, the temperature of the device rises due to the heat consumption of the current, which reduces the light emission power. If the current of the infrared diode is too small, it will affect the performance of its radiated power, but if the working current is too large, it will affect its life and even burn the infrared diode.
When the voltage crosses the forward threshold voltage (about 0.8V), the current begins to flow, and it is a very steep curve, indicating that its operating current requirements are very sensitive. Therefore, the working current is required to be accurate and stable, otherwise it will affect the performance and reliability of the radiated power. The radiant power will decrease with the increase of the ambient temperature (including the increase of the ambient temperature caused by its own heat generation). Explosion-proof infrared lamps, especially long-distance infrared lamps, heat consumption is a problem that should be paid attention to when designing and selecting.
Second, the constant temperature of the explosion-proof infrared camera
Due to the configuration of explosion-proof infrared lamps with high heat generation, after the infrared lamps are activated, heat will be concentrated in the front of the infrared camera during the entire working period (calculated as 12 hours).The temperature at the front end of the cavity is too high. It will definitely affect the normal operation of other components such as the camera.
Third, the fogging and frosting problem of explosion-proof infrared cameras
The formation of fog and frost is caused by the condensation of saturated water vapor in the air, which condenses into frost and fog respectively due to the strong and weak cold environment. During the working process of explosion-proof infrared cameras, especially outdoor cameras, fog or frost is often formed on the window glass of the protective cover due to seasonal changes, temperature differences between day and night, and rain and snow conditions, which make the camera unable to see objects clearly, which directly affects the monitoring effect.
Fourth, the air tightness of the explosion-proof infrared camera
The explosion-proof camera can be fully enclosed, leaving no heat dissipation holes, preventing the entry of dust, moisture and corrosive gases, so that it can adapt to harsh environments with large dust. Such as chemical plants, oil depots, steel processing, military factories, oil tankers, machinery manufacturing, grain processing and storage, etc. Zone 1,2 with explosive mixtures of IIA, IIB, IIC group T1~T6 flammable gases, vapors and air ,and zone 20, 21,22 explosion hazard place formed by mixing combustible dust and air.