ArticleManager1. Network cable production tool
In the process of network cable production, the most important tool is of course the crimping pliers, of course, the function of this crimping pliers is not only for crimping, but also has a lot of “good skills” on the pliers.
There are currently several types of crimping pliers on the market, and the actual functions and operations are similar, we take the above picture as an example, the tool has three different functions.
At the top of the crimping duct is the crimping groove, which provides three types of crimping channels, which are 6P, 8P and 4P, the middle 8P groove is our most commonly used RJ-45 crimping duct, and the next 4P is the RJ11 telephone line crimping groove.
On the back of the crimping pliers 8P crimping groove, we can see the tooth-like module, which is mainly used to press the 8 contacts on the crystal head on the twisted pair.
The front end is the stripping port, and the blade is mainly used to cut the wire.
2. Network line line order
The most widely used network cable used in our LAN networking is Twisted-Pair Cable; TP), twisted pair is composed of 4 pairs of 8 cores of different colors, each of which is twisted together according to certain rules to become a core pair.
Twisted pair according to the electrical performance of the division, can be divided into: three categories, four categories, five categories, super five categories, six categories, seven types of twisted pair and other types, the larger the number, it means the higher the level, the more advanced the technology, the wider the bandwidth, of course, the more expensive the price.
As a transmission medium with low price and excellent performance, twisted pair is widely used in horizontal wiring in integrated wiring systems. Inexpensive, reliable and simple to maintain, twisted pair provides up to 1000Mbps transmission bandwidth, not only for data transmission, but also for voice and multimedia transmission. Today’s Cat 5 and Cat 6 unshielded twisted pair cables can easily provide 155Mbps of communication bandwidth and have the potential to upgrade to gigabit bandwidth, making them the cable of choice for today’s horizontal cabling.
The RJ-45 connector is not protruding from the metal contacts before being crimped
The RJ-45 plug is called “crystal head”, mainly because of its crystal clear appearance. The RJ-45 interface is a connector for connecting unshielded twisted pairs, which is a modular jack structure. As shown in the figure above, the front end of the RJ-45 interface has 8 grooves, referred to as 8P (Position), and there are 8 metal contacts in the groove, referred to as 8C (Contact), so it is also known as 8P8C.
Two-pronged RJ-45 interface
Looking at the RJ-45 interface from the side, you can see the parallel arrangement of metal sheets, a total of 8 pieces, each metal sheet has a protruding transparent frame at the front end, from the appearance of a metal contact, according to the shape of the metal sheet to divide, and there are “two-pronged RJ-45” and “three-pronged RJ-45” interface. The two-pronged sheet has only two side knives, while the three-pronged sheet has three side knives.
3. Twisted pair network cable production process
The first step of network cable production:
We first cut out the twisted pair length that we plan to use using the cutting edge of the crimping pliers.
The second step of network cable production:
We need to peel off the gray protective layer of the twisted pair, we can use the cutting edge of the crimping pliers to cut the wire end, and then put the wire end into the knife edge dedicated to stripping, hold the crimping pliers a little hard and rotate slowly, so that the knife edge cuts the protective glue of the twisted pair.
Remove part of the protective rubber. In this step, it should be noted that the length of the crimping pliers gear from the stripping edge is usually exactly the length of the crystal head, which can effectively avoid stripping too long or too short. If the stripping wire is too long, it will definitely not look beautiful, on the other hand, because the network cable cannot be stuck by the crystal head, it is easy to loosen; If the stripping wire is too short, it cannot be completely inserted into the bottom of the crystal head due to the presence of a protective layer of plastic, resulting in the crystal head pin not being in good contact with the network cable core, of course, it will also affect the quality of the line.
After peeling off the gray plastic protective layer, you can see the 4 to 8 cores of the twisted pair network cable, and you can see that each pair has a different color. Each pair of two cores is made up of a core dyed with the corresponding color and a white interphase core dyed with only a few corresponding colors. The colors of the four full-color cores are: brown, orange, green, blue. Each pair of wires is intertwined, and when making a network cable, the 8 thin wires of the 4 pairs must be unwound, straightened, and straightened one by one, and then neatly arranged in the prescribed line order.
The line sequence described by the T568A standard is, from left to right:
The line sequence described by the T568B standard is, from left to right:
To add, the same equipment is connected with a cross line, and different devices are connected with a straight line!!
The third step of network cable production:
We need to untie each pair of cables that are intertwined one by one. After untying, arrange several sets of cables in turn according to the rules of wiring and straighten them out, and pay attention to avoiding the entanglement and overlap of the lines as much as possible when arranging.
After arranging and straightening the cables in turn, because the cables were previously entangled with each other, the cables will have a certain bend, so we should straighten the cables as much as possible and keep the cables as flat as possible
Straightening the cable is also very simple, using both hands to grasp the cable and then apply force in two opposite directions, pulling up and down.
The fourth step of network cable production:
After we arrange the cables in turn and straighten and straighten, we should carefully check it, and then use the wire cutting edge of the crimping pliers to cut the top of the cable neatly, it should be noted that the cutting should be inserted horizontally, otherwise the length of the cable is not the same will affect the normal contact between the cable and the crystal head. If the protective layer is peeled off too much before, the excessively long thin wire can be cut short here, and the part that is left without the outer protective layer is about 15mm, which is just enough to insert each thin wire into its own trunking. If this section is left too long, firstly, it will increase crosstalk because the wire pairs no longer twist each other, and secondly, the cable may come out of the crystal head because the crystal head cannot press the sheath, resulting in poor contact or even interruption of the line.
After cutting, you should try to press the cable tightly, and you should avoid moving or bending the network cable significantly, otherwise it may also cause several sets of cables that have been arranged and cut to appear uneven
The fifth step of network cable production:
All we need to do is insert the sorted cable into the crystal head. It should be noted that the side of the crystal head with a plastic spring plate is down, the side with the pin is up, so that the end with the pin is pointed away from itself, and the end with the square hole is facing itself. At this time, the leftmost foot is the first foot, the rightmost is the eighth foot, and the rest are in order. When inserting, you need to pay attention to slowly and forcefully insert 8 cables along the 8 cable ducts in the RJ-45 head at the same time, until they are inserted to the top of the trunking.
Before the final step of crimping, we can check from the top of the crystal head to see if each set of cables is tightly pressed against the end of the crystal head.
The sixth step of network cable production:
Of course, it is crimping, after confirming that it is correct, you can insert the crystal head into the 8P groove of the crimping pliers to crimp, after inserting the crystal head, hold the wire pliers firmly, if the strength is not enough, you can use both hands to press together, so that the process of pressing the crystal head protruding from the outside of the pins are all pressed into the crystal and the head, after the force to hear a slight “pop” sound.
As shown in the figure above, after crimping the thread, all the pins protruding from the outside of the crystal head are pressed into the crystal and the head is inside, and the plastic buckle on the lower part of the crystal head is also pressed on the gray protective layer of the network cable.