In the weak current monitoring system, the Internet Cable is an indispensable material for connecting the local area network. In the establishment of the monitoring weak current system, everyone will attach great importance to the selection of important equipment such as cameras, switches, hard disk recorders, decoders, streaming media servers, etc. Don't be too picky, you can use it. This also leads to many problems after the acceptance of many projects. Many of these problems are related to the link of the network cable. Today we will talk about the basic knowledge of network cable!
1. Network cable classification
The network USB Cable is the most commonly used transmission medium in the integrated wiring system. The network cable including Displayport Cable and HDMI Cable is composed of 4 pairs of 8 cores, and each core has a color distinction for data transmission. It is mainly characterized by easy implementation and low price, and can be applied to many different types of scenarios in the integrated wiring system.
①Divided by performance
Network cables are classified according to the ISO/IEC 11801 standard. Commonly used network cables can be divided into five types of cables, five types of cables, six types of cables, six types of cables, and seven types of twisted pair cables.
Category 5 cable: It has been replaced by Category 5e cable for data transmission with a maximum transmission rate of 100Mbps, mainly used in 10BASE-T and 100BASE-T local area networks.
Super class line: It has the characteristics of low crosstalk and low attenuation. It increases the test requirements of near-end crosstalk power and summation compared with the five kinds of lines, and has a higher attenuation crosstalk ratio and smaller delay error. The performance is better than that of the five kinds of lines. It is said that it has been greatly improved, and the maximum transmission rate is 1000Mbps data transmission, which is the lowest entry threshold in quasi-gigabit Ethernet.
Category 6 cable: Compared with Category 5e cable, Category 6 cable improves the performance of crosstalk and return loss, and the transmission performance is much higher than Category 5e cable, which is most suitable for Gigabit Ethernet applications.
Category 6e cable: Category 6e cable is an upgraded version of Category 6 cable. It is mainly used in 10 Gigabit Ethernet, with a transmission frequency of 500MHZ and a maximum transmission rate of 10Gbps. It has a great improvement in alien crosstalk.
Category 7 cable: The starting point of Category 7 cable is shielded twisted pair, the transmission frequency can reach at least 600MHZ, and the transmission rate can reach 10Gbps, which is used for 10 Gigabit Ethernet.
②Divided by material
According to the material, the network cable can be divided into oxygen-free copper, aluminum wire, copper-clad aluminum, copper-clad iron and other types.
Oxygen-free copper network cable: Oxygen-free copper is the best and best quality network cable, suitable for POE power supply, with low resistance, which can reduce the loss of electricity during transmission. In general, the monitoring system is powered by POE, and the network cable made of oxygen-free copper is preferred.
Aluminum wire: The quality of aluminum wire is inferior to that of oxygen-free copper, but there is no major problem in short-distance transmission, and it can be used for equipment connection in home equipment or small offices. The resistance is larger than that of oxygen-free copper, and this type of wire is only suitable for short-distance POE power supply in the monitoring system.
Copper-clad aluminum: This type of network cable is mainly plated with a layer of copper on the outside of the aluminum wire. Because of the skin effect, the electrical conductivity of the aluminum wire is improved to a certain extent, and the resistance is large. The weak current monitoring system is only suitable for short-distance POE power supply. .
Copper-clad iron: A layer of copper is plated around the iron wire. Because of the adhesion effect, the electrical conductivity of the iron wire is improved to a certain extent, and the resistance is large. It is not suitable for POE power supply in the monitoring system.