Classification and Characteristics of Network Cables in Wireless Monitoring Systems

The network cable is the most easily overlooked part of the wireless monitoring system. In the formation of wireless monitoring systems, people often only pay attention to cameras, wireless transmission equipment, switches, video recorders, etc., but for the network cable, the requirements are not too high, only with ordinary network cable, resulting in the entire system signal attenuation, or even normal monitoring Wait.

In fact, the network cable is very critical. Whether in the monitoring system or in the network system. The following is introduced by Lian Technology to apply to the network cable in the wireless monitoring system. And their classification.

Super five-category line: Ultra-5 class has small attenuation, less crosstalk, and has higher attenuation and crosstalk ratio (ACR) and signal-to-noise ratio (Stress Return Loss), smaller delay error, performance is greatly improved. Category 5 is mainly used for Gigabit Ethernet (1000 Mbps).

Category 6 cable: The transmission frequency of this type of cable is from 1 MHz to 250 MHz. The PS-ACR of Category 6 cabling system should have a large margin when it is 200 MHz. It provides 2 times the bandwidth of Super Category 5. The transmission performance of the six types of cabling is much higher than the super five standard, and is most suitable for applications with a transmission rate higher than 1 Gbps. An important difference between Category 6 and Category 5 is that it improves performance in terms of crosstalk and return loss. For a new generation of full-duplex high-speed network applications, excellent return loss performance is extremely important. The basic link model has been eliminated from the six types of standards. The wiring standard adopts a star topology. The required wiring distance is: the length of the permanent link cannot exceed 90m, and the length of the channel cannot exceed 100m.

The common network cables in the LAN mainly include twisted-pair cables, coaxial cables, and optical cables. Twisted pair is a data transmission line made up of many pairs of wires. Its characteristic is that it is cheap, so it is widely used, such as our common telephone lines. It is used to connect with RJ45 crystal head. It has two kinds of STP and UTP. UTP is commonly used.

How to choose network cable, small make up a few points for your reference.

1, see the material

The outside of the cable is almost the same, but there are differences in internal materials, such as pure copper, aluminum wire, copper clad aluminum wire, copper clad wire, iron core wire, and hybrid wire rod.

The pure copper network cable is the best, the resistance is the smallest, it is the highest quality network cable, suitable for PoE power supply, the small resistance can avoid the loss of electricity in the transmission process.

The aluminum wire is second only to the copper wire, and its resistance is slightly larger. There is no big problem in short-distance use. It is suitable for terminals in homes or small offices, or is suitable for short-distance PoE power supply.

The outer layer of the copper clad aluminum wire is plated with a layer of copper. Because of the skin effect, the aluminum wire has a certain increase in its electrical conductivity. Because the resistance is larger, it is suitable for short-distance PoE power supply.

The copper-clad steel wire is electroplated with a layer of copper outside the wire, which has a certain increase in the conductivity of the wire, but its resistance is large and is not suitable for PoE power supply.

The core wire has a large resistance and is only suitable for short-distance transmission and is not suitable for PoE power supply.

The partial wire inside the hybrid wire uses the copper wire to use aluminum. It is only suitable for short-distance use and can be used for PoE power supply. However, when making the crystal head, it must be produced in strict accordance with the wire sequence, otherwise the copper wire cannot be used for power supply and will increase the resistance. , affect the power supply effect.

2, look at the logo of the cable

The identification of the three types of lines is "CAT3", with a bandwidth of 10M, which has been basically eliminated in the ten-megabit network.

The five-category line is identified by "CAT5" and has a bandwidth of 100M. It is suitable for networks below 100M.

The logo of the Cat5e line is "CAT5E" with a bandwidth of 155M and is the flagship product.

The identification of the Category 6 cable is "CAT6" and the bandwidth is 250M. It is used to set up Gigabit network and is the trend of future development.

The characters printed on the real Category 5 line plastic package PI are very clear, sleek, and virtually jagged. The handwriting quality of fake products is poor, some fonts are not clear, and some are severely jagged.

3, feel hand

In addition to seeing, you can also feel the difference in materials between the true and false 5/ultra 5 wires by touching them. True 5/Super 5 cable texture is relatively soft, this is mainly to meet the needs of different network environments, copper wire is generally used in the twisted-pair cable as the core conductor, which is relatively soft (because some network environments may require the cable to make small-angle bends. Folding, if the wire is hard, it is very easy to cause an open circuit.) And some unscrupulous manufacturers add other metal elements to the copper in order to reduce the cost during production. The wires made are relatively hard, not easy to bend, and are easily broken during use. .

4, with a knife

Use a pair of scissors to remove the plastic package PI on the outside of a small stub to expose 4 pairs of cores and watch the cores. The white line in the 4 cores of the True 5/Super 5 cable should not be pure white, but should have the white color of the core line that is paired with it. This is mainly for the convenience of users in making crystals. When the head is different from the line pair. The fakes are usually pure white or the color is not obvious. Another point is the winding density of four pairs of cores. The True 5/Super 5 wire has moderate winding density and the direction is counterclockwise. The dummy line is usually of small density and the direction may be clockwise (less). This is mainly because the production is relatively easy, so the production cost is also small.

5, use fire

The twisted pair can be tested in a high temperature environment to see if the rubber on the outside of the cable will become soft when the temperature is between 35°C and 40°C. The genuine cable will not be soft, and the false one is not certain. There are really adhesives outside the cable that are flame-retardant, and some of them are not flame retardant and do not meet safety standards. Try it when you buy.