Security monitoring system wiring design points

First, the cable selection 1. Camera video signal transmission cable commonly used video transmission cable is a 75Ω series of thin coaxial cable, but the coaxial cable of different diameters of the video signal attenuation is not the same, the cable The coarser the attenuation is. The characteristic parameters of the coaxial cable series are shown in Table 1. It is required to select cables according to Table 1. The thicker the cable diameter is, the smaller the attenuation is and the more suitable it is for long-distance transmission.

Select the cable as follows: When the camera to the sub-monitoring center distance ≤ 300 meters, you can use SYV-75-3; when the camera to the sub-monitoring center distance ≤ 500 meters, you can use SYV-75-5; when the camera to the sub-monitoring When the center distance is less than or equal to 800 meters, SYV-75-7 or SYV-75-9 can be selected; when the distance from the camera to the sub-monitoring center is ≤1000 meters, SYV-75-12 can be selected;

2. The power cable of the camera power cable television monitoring system adopts separate wiring. The master switch is set in the monitoring room. Through the UPS power supply, the entire monitoring system is directly controlled. Under normal circumstances, the power cable is wired according to the AC 220V, and then at the camera end. The adapter is converted to DC 12V. However, some cameras use 5V or 12V, 24V DC, and the power supply is not the same.

3. Camera equipment with electric pan/tilt head and motorized lens cable Camera equipment with electric pan/tilt head and electric lens, in addition to the above video signal cable and cable, the transmission line between the on-site decoder and the control center must also be considered. Cables generally use two-core shielded communication cable (RVVP) or Category 3 twisted pair. UTP core cross-sectional area is 0.3mm2~0.5mm2.

4. Alarm and sound monitoring cables The alarms and monitoring positions at the monitoring positions and corridors are generally 4-wire shielded communication cables (RVVP) or Cat. 3 twisted pair UTP. The cross-sectional area per core is 0.5mm2.

5. Broadcast and Intercom Cables When setting up broadcasts at the warehouses, corridors, factories, etc., the basic principle of cables is: the longer the distance, the thicker the cables. The basic communication distance stipulated by RS-485 communication is 1200 meters. In practice, the RVV-2/1.5 sheath line is used to extend the communication distance to 2000 meters. The length of the visual distance for broadcasting and intercom is different. Cable, twisted pair.

6. Computer network cables Computer network cables fall into two categories. One type of vertical trunk and optical fiber cables are used between buildings, and the other is a horizontal trunk line with 4 pairs of 8-core shielded Super 5 cables. According to the actual conditions of the prison project, high-end 50μm/125μm optical fiber cable was selected between the buildings. The multi-film optical fiber cable is used for sub-monitoring to sub-monitoring centers, and the single-film optical fiber cable is used for sub-monitoring the center to the total monitoring center. Select 4 pairs of /8-core super shielded twisted pairs from the work area to the management room.

Second, the design of the wiring system A prison's wiring system is divided into video, radio intercom, monitoring alarm transmission, data transmission. Video transmission, broadcast, intercom, monitor, alarm transmission line. Based on the specifications and standards of the integrated wiring system. Designed as work area subsystem, horizontal trunk subsystem, vertical trunk subsystem, management room subsystem, equipment room subsystem, building management subsystem. Each subsystem has a reasonable distribution and a clear structure. Strong and weak electricity are routed separately. Learn about introducing data transmission lines below. In the data transmission process, a multi-film cable, a single-fiber cable, and a shielded ultra-5 twisted pair cable are used. Multi-layer fiber optic cables are used between buildings with a distance of ≤ 2000 meters; single-fiber cables are used between buildings with a distance of > 2000 meters; and shielded Category 5 twisted pair cables are used between the desktop and the management room. The basic link length is ≤ 90 meters and the channel link length is ≤ 100 meters. Weak signals in the vertical main line, horizontal main line, a total of metal wire trough, a part of a total of PVC groove walk, enter the prison or working area, according to the general needs of security to go dark buried pipe. The position of the police officer or construction difficulties was changed to open channel. When the cable is bent, the twisted pair maintains a curvature radius of 10 to 15 times, and a PVC hose or a metal hose is sheathed at the corner. The cable runs through the cable trenches and passes through the road when it is buried. When the cable is turned, keep a radius of curvature of 15 to 20 times.

III. Construction and Wiring of the Wiring System Construction work shall be carried out strictly in accordance with the relevant provisions of the comprehensive wiring system design specification. When the wiring is constructed, the following requirements shall be put forward for different locations and environments. Those that do not meet the requirements must be reworked.

1. The open channel of the Buming Trough requires a 10 to 15 year service life without being affected by external forces. Therefore, different installation requirements for different specifications of the trough are required:

(1) When the size of the slot is less than 25mm x 30mm, install a fixing screw at intervals of 15cm to 25cm;

(2) When the size of the trunking is less than 50mm x 50mm, install two fixing screws at an interval of 15cm to 30cm apart, and install them in a wrong position;

(3) When the size of the trough is less than 30mm x 100mm, install three screws at intervals of 15cm to 30cm, and install them in a wrong position;

(4) In general use of metal brackets bracket installation (brackets every 1 meters to 1.5 meters distance), can not install the bracket of the lot, every interval of 15cm ~ 30cm distance, install three sets of screws, and the required positional dislocation installation;

(5) When the "S" type "Z" turn occurs during piping, the line box is installed, and it is not easy to use the hose when turning.

2. The buried pipe of local camera, broadcast, intercom, monitor, and alarm points are all buried and buried. If you already have a pre-embedded pipe, you can use it as much as you can. When it cannot be used, break the wall and set up a buried pipe. As a matter of principle, the wall of the load-bearing wall can't be grooved and holed in principle. However, in some places, because of the special needs of the construction, Party A and Party B will jointly negotiate and consider and open shallower troughs. No holes are allowed.

3. When the vertical trunk line is aligned with the vertical trunk line, use the existing weak electric well and weak electric pipe. Cables are in weak electric wells and weak electricity pipes. Kinking is not allowed, no cross is allowed*, and must be straight. It is bundled once every 1.5 meters or so, and it is fixed with a "U" clip, eliminating the displacement of the cable caused by gravity. 4. Other Requirements for Cabling A prison cabling involves television monitoring lines, broadcast intercom lines, monitoring lines, power lines, alarm lines, and network cables. Requirements for wiring:

(1) Separate the strong and weak currents from each other and take the respective piping;

(2) Keep the distance between 10cm and 30cm when the strong and weak current pipes are in the same direction in the horizontal direction;

(3) When the high-voltage and weak-current pipes are perpendicularly crossed, they shall be sleeved separately to avoid the interference of strong electricity to weak electricity;

(4) Marking both ends of various lines;

(5) Termination points are not allowed in the middle of signal lines and video lines;

(6) In principle, there is no connection point in the middle of the power cord, and in case of emergence there must be a line box;

(7) Signal lines, data lines, power lines, etc. should be straight in their respective slots, without distortion or knotting;

(8) When the hose is connected with the hard pipe, the hose and the hard pipe must be firm and reliable when they enter the slot. After a variety of cable cloths are applied, their performance is tested and meets the specified technical specifications according to the requirements of the wiring standards.