What should be paid attention to in the construction and installation of coal mine monitoring system?

Matters needing attention in the construction and installation of coal mine monitoring system mainly include the following points:

1. The camera must be protected by an explosion-proof protective cover, and the protective cover should also have a certain explosion-proof level according to environmental needs;

2. Due to explosion-proof requirements, infrared LED illumination camera is not suitable for night vision monitoring of underground low light source;

3. In the explosion-proof area of coal mine, all pipelines except for grounding wire and buried pipeline must adopt galvanized steel pipe;

4. If it is a rotating camera, explosion-proof pan/tilt or integrated explosion-proof structure must also be adopted;

5. No matter outside or inside the well, the camera must be equipped with grounding wire to avoid natural explosion or gas explosion caused by current generated by leakage;

6. Explosion-proof pipes must have drainage devices to avoid condensation and make the water in the pipes corrode the pipe wall;

7. There is no need to use explosion-proof isolation joint (drainage pipe) at the joint of metal explosion-proof pipe and metal galvanized pipe, and explosion-proof isolation glue (or sand filling of explosion-proof pipe) should be filled. The explosion-proof pipe should be filled with sand at least 45 cm (18 inch) to have the explosion-proof isolation effect, so as to prevent the spark explosion caused by short circuit in the pipe;

8. The joint between the equipment and galvanized metal pipe or hose shall be isolated by explosion-proof isolation joint;

9. The pipeline connection between explosion-proof area and non-explosion-proof area must also be isolated with explosion-proof isolation joints;

10. All pipelines entering the equipment shall enter the construction from below the equipment or explosion-proof box as far as possible to avoid pipeline looseness or water inflow;

1 1. The power cord, video signal and lightning protection grounding wire must be configured separately to avoid backfire, damage to equipment or explosion;

12. The joints in the junction box of explosion-proof terminal equipment must be lockable or fixed with screw terminals to avoid the line falling off, especially the power supply part, which may cause spark explosion;

13. Most of the image doors in the explosion-proof box of the camera terminal are fixed with screws. When the equipment must be adjusted clockwise, the fixing screws will be tightened one by one to balance the pressure of the box cover and avoid gas explosion due to poor sealing.

14. The system grounding must adopt one-point grounding method. Copper wire shall be used for grounding, which shall not form a closed loop and shall not be mixed with the grounding of high current power supply;

15. When an independent grounding device is used in the explosion-proof monitoring system, its grounding resistance should not be greater than 4Ω (refer to national regulations);

16. If the coal mine adopts optical cable transmission, the optical transceiver shell on the roadway of each well should be grounded, and it is best to connect it in parallel with the equipment of the monitoring points, such as cameras. If the cable rack in the pit is connected, each trunking should be connected to the ground to ensure safety.

18. The equipment that is most vulnerable to lightning strike in the coal mine area belongs to the front camera. If it is erected outside the well, the equipment must be equipped with a lightning rod.