In the process of implementing the integrated wiring project, the placement of the cable has certain skills, and the sloppy is not allowed. Otherwise, the front foot is more laid-up and the rear foot has to be repaired.
First, the cable that is suspended in the air: First we must consider the drooping and pressure of the cable. After testing, decide which binding method to use, and then solve the problem of whether the cable is directly exposed to sunlight.
Second, the cable laid on the outer wall: the cable wired on the outer wall, in the early stage will consider solving the problem of wind and rain, but the main solution is to avoid direct sunlight to the wall and human damage.
Third, the pipe (plastic or metal pipe): the temperature, humidity, heat conduction, etc. in the pipe of different materials are different, so pay attention to the damage of the plastic pipe and the heat conduction of the metal pipe.
Fourth, cloth under the eaves: the cable can be used only when the cable is not directly exposed to sunlight or ultra-high temperature. It is recommended to use the pipeline.
Fifth, laying directly in the underground cable trench: This environment is the smallest control area, the cable trench installation should be regularly dry or wet inspection.
Sixth, underground pipeline: In order to facilitate future upgrades, cable replacement and isolation from surface pressure and surrounding environment, auxiliary pipeline isolation, auxiliary pipeline is a better method. But don't expect the pipeline to remain dry forever, which will affect the choice of cable type.
The first part identifies the cable, saving time and effort
First, the problem
The cable connected to the workstation has no labels or labels that are not good for manual consumption during the installation process or after the installation. For example, inappropriate labeling means that the merchant must use the tone generator and sensory to identify the cable after pulling the cable. More than 1,000 cables were installed in a recent job, and project evaluations showed that each workstation took about an hour to finish working. Proper identification saves each jack nearly 45 minutes of installation time.
Use a widely used identification system to simplify the task of identifying cables when suspected before installation. By dividing the building into sections and giving each part a code, the merchant can identify each cable so the tone generator and sensor bar are not needed. Moreover, if the merchant uses a logical identification system, it is very easy to correct or improve the already-constructed drawings when the end user rebuilds the facility.
1. Divide the installation into sections, and give each floor, orientation, room, and jack a unique logo. If it is a university, give it to each building.
2. All workstations and all equipment rooms, equipment boxes, such as joint blocks and face plates, should be reflected on the blueprint. These tasks should be done well before installation.
3. Label the wiring to do the label on the spot. Durable or the label that the printer has to write to it.
4. Follow the blueprint to end the wiring.
5. After the line is connected, re-mark the line within 6 inches of the node. Make the flag instead of wrapping the logo around the cable as you would when wiring. This will be clear when you look at it.
6. In order to improve the blueprint, make a label for changes and modifications in the wiring junction.
Part II Color Marking Accelerates Cable Identification
Identifying cables is a nightmare for maintenance work. Wire digital sign, rope sign and marking tape are easy to crack and will eventually fall off. Digital tags can be used, but positioning is difficult, because looking for tags is always in the other direction, and close to the roots. Sounding above the cable can sometimes help with positioning, but not in a noisy power environment. Therefore, the maintenance department often prefers to re-wire and is not willing to locate the cable.
The customer label manufacturer's product is very good, but it is expensive and it doesn't stick well once it is dropped. So when you need a label, the label is always not enough.
Color labels can solve this problem. Color labels make it easier to locate from a distance. Such labels are not expensive, and basic color electricians are generally available on hand.
With two basic colors, there are 100 combinations (10*10); there are 1000 combinations (10*10*10) in three colors? Another advantage is that different colors can be used to represent different functions. And department. For example, the first color on the line (the closest to the end) represents the function, the second represents the floor, the third represents the department, and the rest represents the wire identification.
For example, the first position is blue for sound and red for data. In the second position, ten colors represent 10 digits, which distinguish the floors of the building. The third and fourth position of the system is obvious, design color - identify the system to consider the color of the wire.
1. Design the color-identification system to use and add it to the original data or the expanded portion of the file about the cable.
2. Use the box to carry the identification tape, which is convenient and clean.
3. You can also cut a piece of glue on the vinyl protector and carry it. Vinyl sheets can be conveniently placed in notepads and tool cases.
4. Cut off a length of marking tape and wrap it around the cable. There must be at least two long.
5. If the cable is susceptible to physical or chemical corrosion, wrap the strap with a clear red sleeve before closing or joining.
Be careful not to set the color logo near the edge of the cable, in case you have to cut it off to end the wiring.
The third part is the line before pulling the line
When pulling the cable vertically or along the wall, pulling as many cables as possible at the same time saves time and effort. However, a large number of cable bundles will be knotted in the conduit and caught or coupled together at the turn. Untieing or untwisting can damage or even break the cable, especially the small cable No. 5.
In order to prevent this from happening when pulling the cable, it is very important to carefully prepare the head of the cable harness. Shake the cables, knock them into a streamlined configuration, lubricate the head and carefully insert the cable into the conduit or pipe to prevent snagging and knotting.
1. Plan the number and model of the wires to be pulled together. Is it necessary to wrap it tightly? For example, we recently pulled a coaxial cable and three twisted-pair cables in a half-foot electronic metal tube, which means tightly wrapped.
2. Arrange the spools and wire boxes so that the individual cables fit into the planned configuration. Pick a cable for the head. (If you pull several different types of cables at a time, the most solid is the best choice.)
3. Choose two or three cables -- because they are in the same working environment -- place them about an inch away from the head. The head and the first set of wires are spirally wrapped with an electric ring and wrapped to protect the underlying cable.
4. Arrange the two or three cables in the second group, wrapped around the first group about 6 feet behind the electric ring. Where possible, place the cable in the recess of the cable bundle so that it is as streamlined as possible. There must be no recesses when hanging up during the wire drawing process.
5. Do this until the plan is completed. The number depends on whether it is manual or with a crank, specifications, length and routing path, and how many workspaces are served. It is not impractical to lay 10 to 15 cables at a time.
6. Use a slip knot to connect the head to the pull wire, or to the mechanical snake. If appropriate, a lubricant can be used for wiring. Make sure the lubricant is specifically for the tapered head because this part is the most susceptible to friction in the wiring.
7. An installer pulls the wire by hand or crank at one end of the wiring work area. The second person gently inserts the cable bundle into the pipe, conduit or switch to ensure that there is no knotting or slamming, otherwise the cable will be damaged. Both installers should be able to contact, either by voice or by radio.
8. Once the cable bundle is pulled out at the other end, remove the cable or mechanical snake and knock the configuration off. Cut off the one-foot head because it is likely to be corroded or damaged in the cable.
Part IV Measurement of link distance
In the high-speed local network, the line 5 link must be tested and used. The Electronic Industry Federation/Telecom Communications Industry Association 586A drafted the standard for commercial building wiring standards. The maximum cable link distance is 100 meters. In order to demonstrate compliance with standards and to reduce specific regulations, the handheld tester specifies the length of the key based on the nominal propagation rate of cable number 5 to be tested.
Since the chain is primarily a horizontal cable, this requirement is appropriate in most cases; however, there are special cases where swatches, tie lines or cable locations may change the rate of propagation. This happens, and the measured length is not allowed to cause the chain length to be insufficient.
The use of horizontal cable products with continuous footnotes simplifies the task of detecting key lengths again. In order to obtain the quadratic value of the chain length, the length of the horizontal cable and the estimated length of the jumper for all the color switches and intersections are added up.
Record length in the installation
1. When installing, assign labels and record continuous footnotes for horizontal cables
2. After the end of the chain and the final intersection, the length of the horizontal cable and the estimated length of the swatches and jumpers are added to obtain the entire horizontal cable length.
Handheld tester metric length
1. Establish an appropriate nominal propagation rate based on whether the cable is full (refer to the "Nominal Propagation Rate" table).
The nominal propagation rate is essentially determined by the insulating material used. Most of the non-sufficient cable No. 5 is manufactured from commercial polyethylene, and is filled with fluorine-treated vinyl fluoride.
The swatches are generally made of propylene as the insulating material, and the nominal propagation rate is close to that of the non-filled No. 5 cable, which is slightly less - 68 to 69. The nominal propagation rate of the jumper is determined by the cable location.
2. Connect the tester and link with a short color palette (generally provided by the manufacturer). If the horizontal cable length is not particularly long (2:1 or greater) than the total length of the jumper/swatch on the chain, it is recommended that the tester be connected directly to the horizontal cable.
3. Perform a self-test to compare the measured length to the record. The two lengths differ by about 10 feet.
Solution of the difference between the two readings
1. Re-determine the correct nominal propagation rate of the test, if the measurement is gone, retest.
2. Test from the other end to determine the length. If the second end is closer to the recorded value, it may be that the connection at the jack is not good enough to cause the reading to be inaccurate.