Twisted pairs (TP: Twisted Pairwire) is the most commonly used transmission medium in integrated wiring projects. The twisted pair consists of two copper wires having an insulating protective layer. The two insulated copper wires are twisted together in a certain density, and the extent of signal interference can be reduced, and each wire radiation radiation is offset by the electric wave emitted on the other line. The twisted pair is generally winded from each other by two 22 to 26 insulation copper wires. If a pair of or more twisted pairs are placed in an insulating sleeve, they become twisted pair cables. Different lines have different twisting lengths in twisted pair cables (also known as double-to-line cables), generally, with twist lengths, twisted in counterclockwise, and The twist length is over 12.7 cm or more. Compared to other transport media, twisted pairs are limited in terms of transmission distance, channel width, and data transmission speed, but the price is relatively low.
Twisted pairs can be divided into two major categories: shielded twisted pair (STP) and non-shielded twisted pair (UTP).
Among them, there are three classes and 5 classes, and the non-shield twisted pairs are three types, 4 categories, 5 classes, and more than 5 categories. The speed of the 3-class twisted pair is 10Mb / s, and the speed of the 5-class twisted pair can reach 100Mb / s. The super 5 category is more than 155MB / s, only five or more than five categories can be 100Base-TX . Shield twisted pair because of the squid, 獠 阌 阌 懵 懵 窗 窗 靡 跣 跣 冉 下 常 常 常 洌 洌 洌 冉 冉 冉 冉 冉 冉 冉 冉 冉 冉 颐 颐 颐 颐 颐 颐 颐 颐 颐 颐 颐 颐Stealing the 0BASE-T or 100Base-TX network is commonly used in non-shielded 5 classes and super five twisted pairs.
The twisted pair 568 wiring is divided into EIA / TiA 568a, EIA / TiA 568B.
EIA / TIA 568A
1 T3 White Green
2 r3 green
3 T2 white orange
4 r1 blue
5 T1 white 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 blue
6 r3 green
7 T4 white brown
8 r4 brown
We generally use EIA / TIA 568B, as long as both ends of the twisted pair are arranged below.
1 foot 2 foot 3 foot 4 foot 5 foot 6 feet 7 foot & nb! Sp; 8 feet
White orange orange white green blue white blue green & nbsp; white brown brown
The twisted pair is the components necessary to connect to the network equipment in the LAN, which consists of twisted pairs and RJ45 heads, and because improper production often causes the network device connection speed or not. The production method of the twisted pair is described below.
1, straight line: used to connect the two strands of workstations (computers) and hubs in the network
2, cross wire: two strands used to connect the same type of equipment in the network, such as: the microcomputer and the microcomputer.
Proceed as follows:
step 1:
With the twisted pair length required for the scavenging clutch, at least 0.6 meters, up to 100 meters. Then use the twisted palains (actually useless shears) to remove the outer skin of the twisted pair to 2-3 cm.
There are some twisted pair cables contain a soft nylon rope. If you are stripping the outer skin of the twisted pair, I feel that the bare part is too short, and when it is not conducive to the production of RJ-45 connections, I can grasp the twisted pair. The outer skin, and then pinch the nylon wire to the lower side of the outer skin, it can get a long bare line.
Step 2:
At this point, four pairs of 8 lines can be seen, and they are twisted together, and these four pairs are:
White orange / orange, white blue / blue, white green / green, white brown / brown
Due to only four lines (1, 2, 3, 6) in twisted pairs are used for network transmission, the other four lines are useless. So press in the following order:
White orange / orange, white blue / green, white green / blue, white brown / brown (! 即: 1-2 same pair, 3-6 same)
If it is made, all ends of the straight line are arranged in the order of the above, and if it is made, the other end should be arranged in the following order:
White Blue / Blue, White Orange / Green, White Green / Orange, White Brown / Brown (ie: 1-3, 2-6 Exchange) Step 3:
The 8 lines of the ranking order are straight, and the excess lines are removed by the crimping thread, only about 14 mm length is left, pay attention to the incision portion to be neat.
Step 4:
The RJ45 head has a side of contact with the copper sheet, inserts the cut 8 line into the RJ45 head slot, and then compact the RJ45 head with a crimp thread.
Repeat the above steps to do the other end. Such a twisted pair is done.
Note: The maximum transmission distance of twisted pairs is 100 meters, so in the 100M network, the AMP super 5 type twisted pair and RJ45 should be selected.
There are five categories: currently used twisted pairs:
Class 1 rate 1 ~ 2 Mbps;
2 categories of speed 1 ~ 2 Mbps for voice;
3 speed 16 Mbps for 10Baset and 4Mbps token Ring;
Class 4 rate 20 Mbps for 10Baset and 16Mbps token Ring;
5 Class Rate 100 Mbps for 100BaseTX.
