The core member of wiring is patch panel. We all know it’s important, but “what is patch panel?”
1. What is patch panel?
What is patch panel? Many people who have come into contact with the patch panel and even the manufacturer of the patch panel do not know how to define the patch panel. So what exactly is patch panel?
ISO / IEC 11801:2002 defines patch panel as a kind of distribution device suitable for jumper connection. It makes it easier to move and change the cabling system.
ANSI / TIA 568-b defines a patch panel as a cross connect system consisting of pairs of easily managed connectors.
| ISO/IEC 11801：2002 Information technology – Generic cabling for user buildings | ANSI/TIA 568B |
Patch Panel is a kind of centralized and convenient management, which is composed of pairs of connectors and jumper connection; it is used for the connection of vertical subsystem and horizontal subsystem, or the connection of user information point at the office. And the cable of these systems can be centralized management, distribution and adjustment of the wiring device.
2. History of patch panel
According to the data from Wikipedia, the generic cabling system is gradually developed by the voice system. Since 1875, Bell invented the telephone. There is no need for a person to translate the cable instant messaging will gradually rise. Although the telegraph invented by John cook in 1836, it was also capable of instant communication. However, it is troublesome to translate the text into code when communicating. Therefore, after the invention of the telephone, telephone offices were set up all over the world.
After World War II, telephones began to enter ordinary people’s homes from telephone offices. With the rise of intelligent buildings in the United States and more and more telephone installations in every household, together with various other wiring systems. Make each system of the building more and more. The traditional independent wiring system can not meet the needs of safety, comfort and convenience. Therefore, in the late 1980s, at & T launched the generic cabling system (SCS). And launched 110 distribution frame. In the 1990’s, Schneider Electric and other generic cabling manufacturers improved the original 110 patch panel, changed the wiring column to IDC, and added RJ45 Jack in the front end. The patch panel is developed. Moreover, with their unremitting efforts, the patch panel was finally recognized by the American Telecommunications Industry Association (TIA) and the International Electrotechnical Organization (IEC). It has been included in ANSI / TIA 568B published in 2002 and information technology and generic cabling for user buildings published in 2003 (ISO / IEC 11801:2002).
Since then, the network distribution frame began to flourish. At present, patch panel products such as integrated patch panel, modular patch panel, angle patch panel, electronic patch panel have been developed. According to the transmission performance, all kinds of patch panel can be divided into five kinds of patch panel, six kinds of patch panel, super six kinds of patch panel, etc.; according to whether there is shielding layer, it can be divided into non shielding patch panel and shielding patch panel. The advantages and disadvantages of various patch panels will be explained later.
3. Basic structure and material of patch panel
At present, the patch panel on the market is generally 24 ports patch panel, with a length of 19 inches (482.6 mm ± 0.5 mm), a height of 1 u (44.4 ± 0.1), and the color is black.
The front-end shell of patch panel is generally ABS plastic. According to Wikipedia data, ABS plastic has excellent impact resistance, which can adapt to the impact of patch panel during installation and 15 years of service. It has excellent high and low temperature resistance performance, can meet the requirements of – 20 ℃ to 70 ℃ in most areas where patch panel is used at – 40 ℃ to 93 ℃; in addition, ABS resin is insoluble in the common solution in life, which can ensure that the patch panel is not easy to be corroded in use; the surface gloss is good, easy to be colored, and the secondary processing such as electrostatic spraying can be processed into a variety of different colors to adapt to Different requirements of patch panel shell. In addition, ABS resin insulation performance is very good, its insulation performance is basically not affected by temperature, humidity, frequency, can ensure that the link is not short circuit, to ensure effective signal transmission. To sum up, ABS resin is a kind of synthetic resin widely used in patch panel.
The structure of the front end mainly includes: RJ45 Jack and identification area. The identification area is composed of paper identification strip and PE plastic partition board. RJ45 jack is used to plug in the network jumper. There are eight “gold needles” arranged in the hole, and the eight gold pins are generally arranged in an staggered way. Such arrangement structure design can separate electrical signals as much as possible and reduce the interference of signals in the patch panel.
The main material of “gold needle” is phosphor bronze. Phosphorus bronze is the use of phosphorus to remove oxygen in pure copper bronze to achieve the characteristic effect of wear resistance. Phosphor bronze has strong wear resistance, which can meet the requirements of more than 750 plug-in test of information jack, impact resistance, and it is not easy to generate sparks during impact; it can meet the plug-in requirements of jumper of Poe link. In addition, the maximum working temperature of phosphor bronze is 250 ℃, which can meet the requirements of patch panel from 20 ℃ to 70 ℃. Therefore, phosphor bronze is widely used in the sockets of mobile phones, computers, interactive equipment and so on.
However, phosphor bronze belongs to copper alloy, which is easy to oxidize in air. Therefore, the panel manufacturer will carry out the whole body nickel plating process for phosphor bronze. Because nickel contacts with air in a humid environment, a dense oxide film is formed to prevent further oxidation of the main body. The oxidation and rust of copper alloy increases the DC loop resistance and unbalanced resistance, resulting in the increase of insertion loss and return loss. Nickel plating on the surface of phosphor bronze can solve the problem of packet loss and even transmission link failure caused by rust.
When the finished product jumper is jumpered in the patch panel, especially for the distribution frame with frequent adjustment of information points or re patching, the “gold needle” will be worn out. In order to meet the design requirements of 15 years. The “gold needle” must be coated with wear-resistant materials to play a role of wear resistance. In order to achieve the effect of wear resistance, panel manufacturers generally use gold to electroplate the “gold needle”. The information jack with gold plating can meet the requirements of the industry, and it must be able to withstand more than 750 plug-in tests.
The framework of the patch panel is cold rolled steel, which has good mechanical resistance and can withstand various extrusion and impact. It is not easy to deform and the cold rolled steel plate is not easy to rust, which can meet the demand of patch panel for at least 15 years.
The rear end of the patch panel is IDC wiring column and back cover. The back cover is made of ABS plastic. The cover plate is pasted with TIA 568a / B two kinds of thread sequence and core color code.
The shell of IDC striking post is PC plastic. PC plastics are also known as polycarbonate plastics. It is a kind of plastic with good elasticity and impact resistance. It can quickly recover its original shape after being extruded. Therefore, after the impact of the striking tools, the IDC striking post made of PC plastic will not be damaged, but can quickly recover to its original position and clamp the cable, so that the cable will not fall off.
The core of the string is nickel plated phosphor bronze clip. The upper part is used to clamp and break the core skin, contact with the conductor in the core, and transmit the signal to the circuit of the circuit board. The lower part is welded with the circuit board.
The internal part of the patch panel is a circuit board. The six information jacks of the general integrated patch panel share a circuit board, and each information jack of the modular distribution frame has a circuit board. Different brands of patch panel circuit boards are generally different, this is because different brands of generic cabling manufacturers, their cable twist pitch are different. The circuit board of the patch panel is designed according to the structure scheme of the cable. Therefore, the patch panel circuit boards of different manufacturers are generally different.
4. Quality requirements of patch panel
In general, the patch panel will carry out the plug-in test for the information jack, and the industry generally requires that the information jack can pass at least 750 plug-in tests. For the transmission performance, the distribution frame is generally used with cables and cannot be used alone. Therefore, there is no single test for the patch panel. Generally, transmission performance is tested by permanent link test or channel test. Fluke test equipment is used.
In addition, due to the improvement of environmental awareness in recent years. Plastic materials used in the patch panel must pass the environmental protection test requirements of RoHS or Reach.
5. Common patch panel
At present, the common patch panel in the market mainly includes integrated patch panel, modular patch panel, angle patch panel, electronic patch panel, etc. Among them, most of them are integrated patch panel.
From the appearance of the integrated patch panel, 24 RJ45 jacks are packaged in the frame of the patch panel and connected as a whole. Its internal structure is generally 6 RJ45 sockets sharing a circuit board. The advantage of this kind of patch panel is that the production process is mature and the production consumables are low. Therefore, compared with other types of patch panels, the price of integrated patch panel is cheaper. And the construction technology is simple, the construction personnel only need to install the cable to the patch panel. Therefore, it is deeply loved by generic cabling construction personnel. However, the integrated distribution frame (IDF) is an integrated package, and adopts the structural scheme that multiple information points share one circuit board. Therefore, when a port is damaged, it is difficult to replace it. Therefore, once the port is damaged, the port can only be discarded. Moreover, the construction personnel can only purchase the 24 port patch panel which has been pre installed by the manufacturer, and can not delete the port or mix other types of ports according to their actual needs. It is relatively solidified. Moreover, in terms of transmission performance, sharing a circuit board by six information jacks will increase the mutual interference between different information points. The results show that the external near end crosstalk power sum (PS anext) of the system connected to the patch panel is reduced, and the ability to resist external interference is weakened.
The integrated patch panel can not be replaced due to the damage, and the port replacement is not flexible. After a lot of research and improvement, generic cabling manufacturers have made a lot of research and improvement. The modular patch panel is introduced. Modular patch panel, as the name implies, is to package each RJ45 information jack of patch panel independently and then assemble them into the patch panel framework. The advantage of this structure is that each information Jack uses a circuit board independently, and each information jack is packaged in an independent space with PC glue. From the perspective of transmission performance, each information socket of modular patch panel is independent of each other, and the interference between information systems connected to modular patch panel is very small. The anti-interference ability of the access system is enhanced. In addition, due to the independent structure scheme, users can delete the RJ45 port or connect with other types of RJ45 interface or even RJ11 interface according to the actual design scheme requirements when using the modular distribution frame. Therefore, modular patch panel is not only more flexible and more compatible than integrated patch panel, but also can reduce unnecessary waste of wiring construction and save wiring space.
In addition, due to the modular independent design, each RJ45 information module on the patch panel can be taken out for construction and then installed. For the patch panel installed in the wall mounted or embedded cabinet, due to its high installation environment, the construction personnel must use the “herringbone ladder” to carry out wiring construction, and the construction environment is relatively narrow. Using the integrated patch panel for construction, although the construction can be carried out through the reverse assembly distribution frame, the operation space is small, and it is easy to lead to the failure of wiring, so it is not easy to construct. Using the modular patch panel for wiring, the construction personnel can take out the information module and install it back to the patch panel after completing the construction on the ground. Therefore, the modular patch panel can meet the more narrow construction environment.
The disadvantage of modular patch panel is that because of the use of independent structure, it needs to consume more production materials, and because each information Jack uses a circuit board independently, it needs more refined production technology. This is why the price of modular panels is higher than that of integrated panels. In addition, due to the independent design of modular patch panel, the construction difficulty of modular patch panel is more difficult than that of integrated patch panel for the personnel who have to refer to the marking paper to carry out wire laying construction. In addition, because the modular patch panel can be disassembled, very few construction personnel will replace the inferior ones. Install the information module with poor quality, even fake and shoddy information module on the frame of the patch panel, and replace the inferior with the best, cheating the consumers.
The early integrated patch panel and modular patch panel are linear patch panel. Patch panel must be used with horizontal cable management frame to better manage the jumper and beautify the wiring environment. However, the design scheme of patch panel plus wire frame needs to occupy 2U of cabinet space. Because the cabinet is generally 42U.
When the cabinet space is sufficient, it is feasible to use the patch panel to add the cable frame. However, when the cabinet space is limited, the use of structural solutions will occupy too much cabinet resources. With the rapid development of Internet and the shortage of cabinet resources, the defects of this structural scheme are increasingly prominent.
In view of the fact that the linear patch panel and the wiring frame occupy too many cabinet resources, the generic cabling manufacturer has introduced a new patch panel, angle patch panel. This kind of patch panel divides the information jacks which are originally arranged in the same line from the middle to do the breaking type processing. In the middle of the connection is installed with a rotating screw, and the user can rotate the patch panel in the z-axis of 0-120 ° according to the demand. This kind of patch panel can not only isolate part of the crosstalk between cables, but also automatically divide the cable into two parts and conduct ladder type line management. Users only need to wire according to the length of your information jack, and the jumper will jump to the next RJ45 port, and there is no need to borrow the assistant cable rack. This saves 1U of cabinet space.
The disadvantage of angle patch panel is that its structure is more complex than modular distribution frame and integrated patch panel. Therefore, its production process is more complex and needs more production materials. As a result, the price is higher.
In addition, angle patch panel has certain requirements for cabinet installation. Generally, only 800mm deep cabinets can use angle patch panel, and ordinary cabinet using distribution frame will face the embarrassing scene that the cabinet door cannot be closed.
The traditional patch panel will install the identification strip at the port, which is convenient for network managers to manage different information points. However, these identification strips are easy to be lost, and the identification code will become increasingly blurred with the increase of use time, and the identification function will be lost after a certain period of time. This brings a lot of trouble to the later maintenance and management of the network. Therefore, in recent years, a new type of network distribution frame electronic patch panel has become popular. This kind of network distribution frame uses electronic liquid crystal display to replace the traditional paper identification strip. During the construction, the construction personnel can input the port number into the display screen through the computer. As soon as the panel is powered on, the corresponding port number will be displayed. It is convenient for the follow-up personnel to manage the network. Moreover, a part of the electronic patch panel can also count the energy consumption of the real-time Poe, and send the data of the corresponding port to the equipment terminal of the network manager through the wireless LAN, which is convenient for the management of the management personnel.
The disadvantage of the electronic patch panel is that the introduction of the electronic LCD screen increases the production process difficulty of the patch panel. Increased production costs. At the same time, because the use of electronic patch panel needs to supply power to the display screen, on the one hand, it increases the power loss, on the other hand, it also increases the impact of external crosstalk on the cable. In addition, when the data acquisition and display of the electronic patch panel report errors, it may also mislead the network management personnel.
In addition to the patch panel described above. According to the transmission performance, the patch panel can also be divided into five categories, six categories, and six categories. Let’s introduce them one by one.
Category 5 patch panel is used in Category 5 Cabling System. The transmission bandwidth is 155mhz, and the maximum transmission capacity is 1000Mbps Ethernet. It once dominated the generic cabling market for a long time. With the development of the Internet and the increasing demand for large bandwidth network, its market share has gradually decreased;
Category 6 patch panel is suitable for Category 6 cabling system. The transmission bandwidth is 250MHz, and it can stably transmit 1Gbps Ethernet network, which is in line with the information technology published in 2018. The general cabling of user building group (ISO / IEC 11801:2018) requires the use of category 6 and above cabling systems for building horizontal links;
Category 6 patch panel is used in Category 6 cabling system. The transmission bandwidth is 500MHz, which can stably transmit 10Gbps Ethernet network, which is suitable for the wiring of future intelligent buildings.
In addition, according to whether there is a metal shielding layer. The distribution frame can be divided into unshielded patch panel and shielded patch panel. Due to the use of galvanized copper shell as the shell of the information module in the shielding patch panel. It can effectively shield electromagnetic interference. It is suitable for the government, the military and other institutions with confidentiality needs, and also suitable for hospitals, factories and other units with strong electromagnetic interference sources. However, the price of shielded distribution frame is more expensive, and the requirements of construction technology are higher than that of unshielded patch panel. The above scenarios are not recommended.
The unshielded patch panel does not have metal shielding layer, and the shell of information jack is ABS rubber and PC plastic. The shielding effect of electromagnetic wave is poor. Suitable for general cabling environment. cheapness. It is also the most commonly used patch panel.
In addition, there are some other patch panels on the market. Due to the limited space, this paper briefly introduces two types of patch panels: straight through patch panel and patch panel with optical fiber.
The straight through patch panel is an empty patch panel with double RJ45 sockets. When in use, the cable is directly crimped to the crystal head and then directly inserted. As the cable installed at one end of the patch panel is a single twisted pair. In the actual construction, it is directly connected with the crystal head. The pulling force of a single twisted pair to the port is very large. It is very easy for the crystal head installed on the single twisted pair and the gold needle in the information jack of the distribution frame to cause poor link contact or even port damage due to the tension of the single twisted pair, resulting in the cable link being blocked.
With optical fiber patch panel, plastic optical fiber is generally installed on the patch panel. Use with cable with optical fiber. It can achieve the goal of one second line finding. However, according to the requirements of GB 50311, the service life of permanent link is generally 15 years. The quality can reach the industry standard and standard construction of the wiring link in normal use will not appear quality problems. So this design is a bit impractical.