Monitoring cameras generally requires two types of wires: the first is a power cord for power supply, mainly divided into DC power supply and AC power supply. Select the protective cover cable with appropriate thickness specifications according to the length of the power supply distance. The second is the signal cable. For the coaxial simulation camera, the coaxial video cable is mainly used, and the network digital camera mainly uses the network cable (copper cable twisted line).
Power cable selection and precautions
[Line diameter and transmission distance] It is recommended to use RVV2*0.5 power cords in close range. It is recommended to use RVV2*1.0 or RVV2*1.5 or more power cords. However, if the distance is generally within 20 or thirty meters, the equipment power is not high, and the 2 -core wires in the network comprehensive wire can be powered by power.
[Power attenuation] It should be noted that there are not too many cameras in the same monitoring power band, otherwise it is easy to cause voltage instability. DC power supply can be used directly at close range. When power supply is supplying long distances (above 100 meters), it is best to communicate in the middle. It is recommended to use an AC 220V total power cord to pass to the camera. The current loss is low, the more stable the image is. Waterproof line boxes should be added outdoors to play a role in protecting.
In addition, the protective cover power cord has a certain waterproof, but the outdoor wiring and other need to be laid, and the waterproof insulation treatment is done at the head of the line.
The choice and transmission distance of the video cable of the coaxial axis simulation equipment
For analog or coaxial high-definition camera, the transmission of signals uses the same axis video cable, such as SYV73-3 or SYV75-5 video cable. Essence
[Transmission distance of coaxial cable with shielded coaxial cable]
BNC cable specification type
Transmission distance> 500M
300M <500M <500M
Transmission distance <300M
Note: If there are many BNC heads that need to be welded, you need to ensure that the welding ting is not loose and constantly cracks; the welding ting and cable cannot be bent, virtual welding, etc., otherwise it will cause ghost shadows.
[Twisted tiered transmission] When using twisted tiered transmission during the construction process:
1) If the front end is Haikang’s coaxial high -definition (HDTVI) camera transmitted with twisted lines, and using a BNC converter dedicated to Haikang, it can ensure that the maximum transmission of about 200m screen color is normal.
2) The twisted wire cable uses the rough core cable as much as possible, such as the two of the super five types of network cables.
[Line diameter and transmission distance] (Engineering experience, for reference only):
1) When the distance from the camera to the monitoring center is ≤300 meters, SYV-75-3 can be selected;
2) When the distance from the camera to the monitoring center is ≤500 meters, SYV-75-5 can be used;
3) When the distance from the camera to the monitoring center is ≤800 meters, you can choose SYV-75-7 or SYV-75-9;
4) When the distance from the camera to the monitoring center is ≤1000 meters, SYV-75-12 can be selected;
Selection and precautions for network cables
The network digital camera is recommended to use the 8 -core twisted lines of over five or six categories. If there is interference in the use environment, it is recommended to choose a shielded twisted wire.
The transmission distance of the network cable should not exceed 100 meters in theory. It is recommended not to exceed 80m in actual construction. If the distance between the camera and the recorder is far away, the middle -class multi -desk switch can be transmitted in the middle, but the number of layers of the switch should not exceed 3 layers, avoiding data loss due to the large number of switch layers. If the distance is far, you can use the fiber+fiber transceiver to transmit it.