Cabinet cable details (1)

The horizontal twisted pair wires in the cabinet are located on the rear side of the Cabinet. In the past, the twisted pair wires were not organized or simply bundled before being immediately mounted to the distribution frame. At that time, from the back of the Cabinet, the horizontal twisted pair wires were hanging like waterfalls, or several nylon cable ties can be bundled on either side of the Cabinet. Everyone is concerned about the performance testing of each twisted pair wire.

With the improvement of the wiring level, the cabling system's engineering has passed the construction technology and layer-by-layer checks to ensure that each line can pass the performance test. At this time, people's attention turned to beautiful.

According to the national standard, cables in the vertical bridge should be bundled once every 1.5 meters to prevent cable deformation caused by tension caused by the weight), there is no requirement for horizontal bridge. The terminal panel, Cabinet, distribution frame, and distribution box must be parallel at the two corners according to the standard. Therefore, the appearance of the wiring system is mainly concentrated in the cable section of the data center.

Cables in the IDC often enter the rack or wall mounted rack. This article will mainly involve the cable management process of Cabinet distribution frames.

On the front of the Cabinet, the manufacturer has created components such as the distribution frame and jumper manager of various shapes. The appearance of the front is no longer a problem. The appearance of the rear side of the Cabinet is often not noticed by people, resulting in the failure to let people visit the interior of the Cabinet after the project is completed.

In the data center, each line should start from entering the data center until the modules of the distribution frame are horizontal, horizontal, and vertical. In addition, according to the requirements of electronic equipment, each bend angle is fixed with a cable, to ensure that the cable has a certain turning radius at the bend angle, while at the same time horizontal and vertical.

The above requirements also apply to the rear side of the Cabinet. Since horizontal twisted pair wires are no longer ideal for waterfall deployment, horizontal twisted pair wires in the cabinet should be managed.

The term line management has been heard by many construction workers, but its meaning is different because the line management techniques are different.

In order to make the cables look beautiful, I have seen three types of cable management techniques:

Waterfall shape

This is a relatively old wiring style, and sometimes it can be seen. It uses the artistic image of "huaguoshan Water Curtain Cave", and directly hangs the twisted pair wires from the distribution frame module. When the distribution is neat, there is a very beautiful sense of attention, 24-48 twisted pair wires on each layer ).

The advantage of this shape is that it saves manpower on the line, but there are many disadvantages. For example, it is easy to damage the shape when installing network devices, or even it is difficult to install network devices in place; the weight of each twisted pair changes to tension, acting on the rear side of the module. If the twisted pair is not bundled before the end point, the tension may separate the module from the twisted pair for several months or years, causing a disconnection fault; in case a module in the distribution frame needs to be re-connected, the maintenance personnel can only access the "water curtain" for construction, sometimes wearing dozens of twisted wires, and because there is no light source in both directions, the client cannot be seen clearly during the connection.

Reverse line

The reverse wiring is performed after the module end of the distribution frame is connected and passes the test. The method is to adjust the cables from the module to the Cabinet and from the cable tray. The advantage of doing so is that after the line is tested, the line will not be re-adjusted because a pair of wires cannot pass through the test, but the disadvantage is that the inlet ports and distribution frames at both ends have been fixed, A large number of chaotic lines are usually located at the bottom of the Cabinet ).

The reverse line is generally a human line, which is completed with the naked eye and hands.

The advantage of the reverse line is that the test has been completed and there is no need to worry about the cable length on the rear side of the Cabinet. The disadvantage is that the two ends of the cable have been fixed, and there will be a lot of crossover between the cables. It is very laborious to make the cables neat and tidy, and there must be a pair of twisted wires scattered between the two fixed ends, this location is often in the floor when going offline) or when the ceiling is going online ).

Forward line

Forward line management is performed before the distribution frame end is connected. It segments cables from the entry ports of the data center until the modules of the distribution frame. After the cabling, perform the connection and test.

The goal of the forward line management is to bring the horizontal twisted pair wires from the inlet ports of the data center or the network zone of the data center to the wiring cabinet, in units of each 16/24/32/48-port distribution frame, A horizontal twisted pair harness is formed. The crosstalk between wires produced when all twisted pairs are parallel within a short distance does not affect the overall performance, because most of the twisted pair wires are laid in the cable trays and cables, these wires are scattered and not parallel; each twisted pair wire in the cabinet is bent and laid to the rear side of each distribution frame. The whole process still keeps the twisted pair wires in the harness parallel throughout the whole process. The twisted pair wires corresponding to the module are extracted from the bottom of the harness on the rear side of each module. After checking the cables are correct, they are fixed on the cable holder behind the module or in the module hole of the distribution frame.

The advantage of forward cable management is that the cables in the IDC room are neatly arranged at every point without any cable crossover. The disadvantage is that if the cable itself is damaged during cabling, the test will fail, resulting in a new line. Therefore, the premise of Forward line management is to have a sufficient grasp of the quality of cables and threading.

The advantage of forward cable management is that all the self-inlet ports and distribution frames are neat and parallel in the network zone or weak current room of the master data center, which is very beautiful. The disadvantage is that the construction personnel must have a full grasp of their own construction quality. Only on the basis of basically no re-connection can the construction of the forward line be carried out. In this article, based on the current situation that the wiring engineering company can grasp the engineering quality, we recommend adopting the forward line management process.

A total of 1.5 people are required for the forward line. The time required for finding a line number is about 40 minutes per 24 lines ). The required tools are as follows:

List of Forward line tools

Cable management board:

The cable management board is an essential tool for forward cable management. It can be made in the field using fiber boards, laminate or wood boards, or after being made in the company.

The method for making the cable board is very simple: to measure the cable diameter of the twisted pair wire used, and add 2-4mm to form the hole diameter of the cable board, and then select the gap between the hole and the hole according to the strength of the Board, draw 5 lines horizontally on the board, draw 5 lines vertically, and leave the space to write numbers to determine the length and width of the Board. After cutting or sawing the excess part, drill 25 holes at the intersection of the dashes with the specified aperture, and then use coarse sandpaper to chamfer all the edge, write or engrave it horizontally) 1-5 number, in vertical write or engraved) the number of the A-E after success.

The cable management board is a 25-hole square board corresponding to the 24-port distribution frame of the appropriate size 5 × 5 hole Management Board, you can also choose 4 × 6, 8 × 8 specifications), single-sided printing, each hole can wear one horizontal twisted pair. It can be imagined that when the twisted pair wires are connected to the cable board, their relative positions are basically fixed. It is not easy to see a large dislocation when binding according to their positions, cable crossover is not easy.

Line table:

Objective: To use a 24-port 1U distribution frame with cables directed from the back of the distribution frame to the distribution frame. Twisted Pair wires are pulled from the bottom of the wiring harness and switched to the distribution frame, ensure that the twisted pair wires on the top are always arranged to the last 21 ~ Module 24.

Note: The number 1-24 in the figure is the number of the distribution frame module. It is not the one-to-one line number that really needs to be filled in with the distribution frame module number.

The cable management board must use the corresponding line management table to work with the line management board.

A line table is a table defined by humans. When a 5 × 5 line board is used, the line table contains five rows and five columns, and each cell corresponds to a hole. You can enter a line table in a variety of ways, each of which corresponds to a sort order. In the right figure, the following figure shows the number of the module on the distribution frame ):

When you fill in the line management table, fill in the line number corresponding to the 1-24 ports of the distribution frame in the line management table, so that the line number and the module number of the distribution frame are one-to-one. In general, when the layout of the distribution frame is completed, you can use the EXCEL linkage function to automatically form a line table for each distribution frame.