Several principles for organizing cabinets

Cabinet cable management has always been a headache for many people. The cabinet-type distribution frame has become the main body of the computer room distribution frame, so cable management is also an important part. How to organize the cabinet well is also part of the competitiveness of many enterprises. The following is aimed at this Explain the knowledge in this area.

Several principles for organizing cabinets

The network cables should be arranged according to the topology of the network and the existing equipment conditions; in principle, the cabinet power cables and network cables should be arranged separately, and the equipment should be placed properly to avoid mutual extrusion, avoid too high or too low, and avoid too close to each other; If there are too many devices in the cabinet, the devices should be numbered; the source of each line should be indicated in an appropriate position, and different connections (such as general network connection lines, crossover lines, dedicated lines, etc.) should be identified differently Method: The network cables are arranged according to the room number. It can be summed up in one sentence: clear layout, regular line order, clear marking, and easy maintenance.

Cabinet finishing steps

1. Preliminary preparation

First of all, the user should be notified to organize the cabinet without affecting the normal work of the user.

Then draw out the wiring diagram and equipment location diagram inside the cabinet according to various factors such as network topology, existing equipment, number of users, and user grouping.

Next, prepare the required materials: network jumpers, label paper, and various types of plastic cable ties.

2. Organize the cabinet

Install the cabinet:

You need to do the following three things by yourself: first, use the screws and nuts that come with the frame to tighten the fixing frame; second, knock down the cabinet and install the movable wheels; third, according to the location of the equipment Adjust and add baffles to the mount. Organize lines:

Group the network cables, and the number of groups is usually less than or equal to the number of cable management racks behind the cabinet. Bundle the power cords of all devices together, insert the plugs from the rear through hole, and find the respective devices through a separate cable management frame.

Fixed equipment:

Adjust the baffles in the cabinet to a proper position, so that the administrator can see the operation of all the equipment without opening the cabinet door, and add baffles appropriately according to the number and size of the equipment. Be careful to leave some space between the baffles. Place all the switching equipment and routing equipment used in the cabinet according to the pre-drawn diagram.

Cable labeling:

After all the network cables are connected, it is necessary to mark each network cable, wrap the prepared post-it note on the network cable, and mark it with a pen (generally indicate the room number or what it is used for), and the label is required to be simple and easy to understand. Crossover network cables can be distinguished from ordinary network cables by using sticky notes of different colors. If there are too many devices, the devices should be classified and numbered, and the devices should be labeled.

Introduction to wire management process

1 waterfall styling

This is an older wiring style that can still be seen sometimes. It adopts the artistic image of “water curtain hole”, directly hangs the twisted pairs from the module of the distribution frame, and has a very beautiful sense of hierarchy when distributed neatly (24-48 twisted pairs per layer).

At present, it can still be seen that the rear of some wiring cabinets adopts a waterfall-type cable management process, that is, the cables are directly swayed from the rear of the wiring panel to the ground without any binding. The advantage of this is to save labor and reduce interference between lines (crosstalk).

The waterfall cable management method is the most common cable management method. It uses nylon straps to bind the cables to the columns and beams inside the cabinet. It does not consider the appearance, but only ensures that the space in the middle can be used for network equipment.

The advantage of this shape is that it saves manpower for cable management, but it has many disadvantages, such as:

1. It is easy to damage the shape when installing network equipment, and even the phenomenon that it is difficult to install the network equipment in place;
2. The weight of each twisted pair becomes tension, which acts on the rear side of the module. If the twisted pair is not bound before the termination point, then this pulling force may separate the module from the twisted pair after months or years, causing a disconnection fault;
3. In case a certain module in the distribution frame needs to be re-terminated, the maintenance personnel can only probe into the “water curtain hole” for construction, sometimes wearing dozens of twisted pairs, and due to the common There is no built-in light source, which makes it difficult to see clearly during termination, which increases the probability of termination errors.
4. Reverse line management

Also known as reverse routing. Reverse cable management is performed after the modules of the distribution frame are terminated and passed the test. The method is to arrange the wires from the module to the outside of the cabinet, and at the same time arrange the wires in the bridge. The advantage of this is that after the test, the cable will not be re-arranged because a certain twisted pair fails the test, but the disadvantage is that since the two ends (the cable inlet and the distribution frame) have been fixed, the There is bound to be a lot of messy wires somewhere (usually the bottom of the cabinet).

Reverse wire management is generally manual wire management, and the wire management is completed with the naked eye and hands. Since there are a large number of cables in the cabinet, they are crossed and entangled with each other when they are threaded, so this method consumes a lot of time and cannot improve work efficiency.

The advantage of reverse cable management is that the test has already been completed, and there is no need to worry about the length of the cables at the rear of the cabinet. The disadvantage is that because the two ends of the cable have been fixed, there will be a large number of crossovers between the cables. The location is often under the floor (when the line is coming in from the bottom) or on the ceiling (when the line is coming in from the top).

3. Positive line management

Forward routing is also called feed-forward routing. Forward cable management is the cable management before the distribution frame is terminated. It often starts from the cable entrance of the computer room (if it is twisted pair cable management from cabinet to cabinet, it starts from the distribution frame in one of the cabinets), arranges the cables segment by segment, up to the rear of the module on the patch panel. Perform termination and testing after cable management.

The goal to be achieved by forward cable management is: the horizontal twisted pair from the cable inlet of the computer room (or the network area of ​​the computer room) to the distribution cabinet forms a unit of 16/24/32/48-port distribution frame. The bundled horizontal twisted-pair wire harness, all the twisted-pair wires in each bundle are all parallel (the crosstalk between the wires generated by the parallel twisted-pair wires in a short distance will not affect the overall performance, because the bridges and wire tubes are laid Most of each twisted pair, this part is scattered and non-parallel), and all the wire bundles are parallel; each twisted pair in the cabinet is bent and laid to the rear of each distribution frame, In the whole process, the twisted pairs in the wiring harness are still kept parallel throughout. Pull out the twisted pair corresponding to the module from the bottom of the wiring harness at the back of each module, and fix it on the wire support frame behind the module or pass it into the module hole of the distribution frame after checking.

The advantage of forward cable management is that it can ensure that the cables in the equipment room are neat at every point, and there will be no cable crossing. The disadvantage is that if the cable itself has been damaged during threading, failing the test will cause rewiring. Therefore, the premise of positive cable management is to have sufficient confidence in the quality of cables and threading.

Positive wire management process

In the process of forward cable management, the cooperation of wiring materials is required, and the use of cable management boards and cable management tables, combined with the cable management process, can complete a beautiful, reliable, fast and reserved effect at the same time. The following introduces the basic construction process of forward line management in the most common way of right-in and top-out line management:

1. Fix the distribution frame in place, install the bracket on the back, and put the panel paper with the printed line number on the distribution frame (or paste it on the distribution frame) on the front. If the module of the distribution frame can be removed, then The module should be removed;
2. Positioning of the cable management board: the direction of the cable management board should be determined before threading, so that the cable management board does not need to reverse the direction during the cable management process, so that the E1 hole can be naturally aligned with the No. 1 module. Holes 2-5 on the wiring board are parallel to holes 2-5 on the distribution frame. Usually, you can use this method for positioning: first place the cable management board vertically behind the No. 1 module, so that the E1 hole faces the No. 1 module (the side with the word faces the No. The future routing direction is to move to the cable inlet of the computer room. When moving, ensure that the cable management board only moves in parallel and does not rotate. When the cable management board reaches the cable inlet, write down the orientation of the cable management board (mainly A1 hole location), for the subsequent use of each cable management board;
3. Threading of the cable management board: Next to the cable entrance of the machine room, adjust the direction of the cable management board according to the position determined in 2, and thread the horizontal twisted pair wires into the cable management board according to the wire number according to the cable management table (with The side of the word is facing itself, and the thread penetrates into the board from the side without the word), this process is generally completed by two people: one person finds the line number (just find the line number required by the line management board) and Separate it from the other cables and one person thread the wires through the corresponding holes in the cable management plate. It should be noted that all twisted pairs should pass through the cable management board, that is, the cable management board should be placed next to the cable inlet, so as to ensure that all twisted pairs entering the computer room are sorted out;
4. Routing cable management: First use Velcro (or nylon cable ties) at the root of the outer side of the cable management board (or nylon cable ties) to tie the twisted-pair wires penetrating into the cable management board into a bundle; then place the cable management board along the specified Move the routing to your own direction. After moving 100mm, use Velcro (or nylon cable ties) on the outer root of the cable management board to bind it again (to prevent the previous binding from loosening). It should be the wires around the periphery of the cable management board, and the wires in the middle of the cable management board are inside the wire harness. After the determination, the relative parallelism of all the twisted pairs must be kept to the rear side of the farthest module of the distribution frame (that is, the first 24 modules at the rear side); continue to move the cable management board about 200mm, and tie it with Velcro (or nylon cable ties) on the outer root of the cable management board. The wires are transferred from the outer layer to the inner layer, and the inner layer wires are not allowed to be transferred to the outer layer; they are shifted sequentially until the distribution frame;
5. Wire harness fixing: In the process of cable management, if you encounter the cable hole on the bridge frame or the cable tie plate in the cabinet next to it, you should bind the cable harness on the bridge frame or cabinet while tying the cable harness to prevent the cable harness from sliding down;
6. Corner line management: When a turn is encountered during the translation process, the cable management board must be close to the turning corner and follow the turn beside the corner. It is not allowed to bind and then paste the corner (because the line inside the corner Short, the outer wire is long, so if you turn in a straight line and then turn, the wire harness at the corner will definitely be deformed). This requires that all wire harnesses must be bound on site, and cannot be moved to the site after binding in advance;
7. Bracket cable management: When the cable management board reaches the bracket behind the distribution frame, first bind the wire harness on the bracket, and then move forward. Every time it reaches a module, bind the wire harness once, and then divide Display the line number corresponding to the module. This process should be equipped with 2 people: 1 person to divide the line, 1 person to pull the line from the back of the distribution frame to the front of the distribution frame (if the module can be removed, pass the line from the module hole to the front), and 2 people at the same time Check whether the line number is consistent with the panel number on the patch panel;
8. Take the exited cable management board to the cable inlet again, use the cable management table of the next 24-port distribution frame, and repeat 1-8 in turn to complete the cable management work of the next bundle of cables until all are completed.

Multi-bundle cable management (branch management)

When there are multiple distribution frames in the cabinet, the wiring harness of each distribution frame should be managed separately. However, due to the limited width of the binding board in the cabinet (generally, the width is 100mm), only 3 to 4 bundles of 24 wire harnesses can be bound side by side, and a maximum of 2 binding boards can be placed on the right side of the cabinet with a depth of 800mm (inside the cabinet). The horizontal twisted-pair wires should be bound from one side to avoid affecting the appearance), that is, the goal of binding 200 horizontal twisted-pair wires may not be achieved. At this time, the secondary wire management method can be used. First, use the 8×8 wire management board to tie out 48 wire harnesses (6×8). After reaching a certain height, add a 5×5 wire management board to divide the wire bundle into 2 After finishing, continue to manage the cables to the distribution frame.

The starting point for forward cable management can be the cable entrance of the cabinet, the bridge opening, the entrance of the equipment room, or even start the cable management from the panel of the work area (not recommended).