Little knowledge about twisted pair wires

Twisted Pair wires (TP: Twisted Pairwire) are the most commonly used transmission medium in integrated cabling. Twisted Pair wires are composed of two copper wires with an insulating protective layer. The two insulated copper wires are twisted together at a certain density to reduce signal interference, the electric waves emitted by each wire during transmission are offset by the electric waves sent from the other wire. Twisted Pair wires generally consist of 22 ~ The No. 26 insulated copper wires are wound together. If one or more pairs of twisted pair wires are placed in an Insulating Sleeve tube, the twisted pair cables are formed. In a twisted pair Cable (also known as a twisted pair cable), different lines have different twist lengths. Generally, the twist length ranges from 1cm to 14cm, and is twisted in a counterclockwise direction, the twist length of the adjacent line is above 7cm. Compared with other transmission media, twisted pair wires are limited in terms of transmission distance, channel width, and data transmission speed, but the price is relatively low.

Twisted Pair wires can be divided into two categories: Shielded twisted pair STP and unshielded twisted pair UTP.
The shielded twisted pair wires are divided into three categories and five categories, and unshielded twisted pair wires are divided into three categories, four categories, five categories, and over five categories. The speed of the three types of twisted pair wires is 10 Mb/S, the speed of the five types of twisted pair wires can reach 100 Mb/S, and the speed of the five categories can reach more than 155 Mb/S. Only five or more category 5 wires can be used for 100Base-TX. Shield twisted pair wires because the outer layer of the cable has an aluminum mooring package to reduce the radiation, making it more troublesome. In addition, the price line is more expensive than the unshielded twisted pair wires, therefore, among the 10Base-T or 100Base-TX networks, we often use unshielded cat5e and cat5e twisted pair wires.

Cabling Standards for twisted pair wires 568 are classified into EIA/TIA 568A and EIA/TIA 568B.

EIA/TIA 568A 1 T3 white-green 2 R3 green 3 T2 white orange 4 R1 blue 5 T1 white and blue 6 R2 orange 7 T4 white Brown 8 R4 Brown EIA/TIA 568B 1 T2 white orange 2 R2 orange 3 T3 white-green 4 R1 blue 5 T1 white and blue 6 R3 green 7 T4 white Brown 8 R4 Brown

We generally use EIA/TIA 568B, as long as the two ends of the twisted pair are arranged as follows.

1, 2, 3, 4, 5, 6, 7, 8
White orange white green blue white blue green white Brown

Twisted Pair wires are essential components for connecting network equipment in Lan. They are composed of twisted pair wires and RJ45 headers. Due to improper configuration, the connection speed of network equipment is often reduced or disconnected. The following describes how to create a twisted pair.

1. wired: twisted pair wires used to connect workstation computers in the network) to hubs
2. Crossover line: used to connect the twisted pair wires of devices of the same type in the network, for example, between a microcomputer and a microcomputer.

The procedure is as follows:
Step 1:

The length of the twisted pair Cable required to be cut by mistake at the diagonal port is at least 0.6 meters, and cannot exceed 100 meters. Then, use the twisted pair wires to strip the cables. The outer skin of the twisted pair wires is removed by 2-3 cm.

Some twisted pair cable contains a soft nylon rope, If you strip the outer skin of the twisted pair, the exposed part is too short, not conducive to the production of RJ-45 connector, you can hold the outer skin of the twisted pair wire, and then hold the nylon wire to the bottom of the outer skin to obtain a longer exposed line.

Step 2:

At this point, we can see eight lines in four pairs. They are twisted together. The four lines are:
White orange/orange, white blue/blue, white green/Green, white brown/brown
Because the twisted pair has only four lines 1, 2, 3, and 6) used for network transmission, the other four lines are useless. Therefore, we need to sort them in the following order:
White orange/orange, white blue/Green, white green/blue, white brown/brown! That is, 1-2 of the same line, 3-6 of the same line)

If the two ends of the express Connect line are arranged in the above order, if the cross line is made, the other end should be arranged in the following order:

White-blue/blue, white-orange/Green, white-green/orange, white-brown/BROWN: 1-3, 2-6 swap)

Step 3:

Straighten the eight lines in sequence, and remove the extra lines with a crimping tool. The remaining length is about 14mm. Note that the cut part should be neat.

Step 4:

Place the RJ45 head in contact with the copper on one side up, insert the cut eight lines into the wire slot of the RJ45 head, and compress the RJ45 head with a crimping clamp.

Repeat the above steps to complete the other end. Such a twisted pair will be ready.

Note: The maximum transmission distance of twisted pair wires is 100 meters. Therefore, in a m network, select a pair of over 5 categories of twisted pair wires and RJ45 headers.

Currently, five common twisted pair wires are used:

Class 1 speed 1 ~ 2 Mbps; Two types of rate 1 ~ 2 Mbps for voice; Class 3 rate 16 Mbps for 10 BaseT and 4 Mbps Token Ring; Class 4: 20 Mbps for 10 BaseT and 16 Mbps Token Ring; Category 5: 100 Mbps, used for 100 BaseTX.