Under RJ-45 it is customary to understand, first of all, a connector and a connector for it. He came into use as the main interface for the installation of local networks. Then it was adopted by many Internet service providers, which is implemented using the PPPoE protocol. In this article we will tell you about the most popular connector for mounting RJ-45 networks, its features and, most importantly, about the pinout.
Read in the article
- 1 RJ-45 connector pinout
- 1.1 Standards
- 1.2 Schemes
- 1.3 Pinout for 8 pins
- 1.4 4-core pinout
- 2 How to crimp the cable correctly
RJ-45 connector pinout
Pinout call the arrangement of the contacts on the connector plug in such a way that they match the contacts on the plug. Depending on the required network configuration, their location may vary.
Standards
There are no unique standards for RJ-45, since this standard does not officially exist. RJ-45 is erroneously called 8P8C, which is similar in appearance to 8P4C from the RJ-45S standard. It should have 8 pins and 8 pins. Since the connector includes both a plug and a socket, both parts must have the same number of contacts. Nevertheless, further we will talk about cases when, in order to save money, you can reduce their number to 4.
Schemes
The most interesting thing here is the schematics. According to the accepted norms, the wires in the Ethernet cable are colored each in a different color. And for the functioning of a particular network configuration, the corresponding color marking is applied. For 8-core cables, when creating a full-fledged network, there may be an option: when connecting peer-to-peer devices and when connecting peer-to-peer devices. Therefore, the schemes are different for them.
Pinout for 8 pins
The UTP cable used to build local networks has 4 pairs of wires. Each pair has its own common color. In each pair, one of the wires is painted in the main color completely, the other - partially, forming, for example, a combination of white-green or white-blue.
There is even a special TIA / EIA-568 standard for correct crimping. It assumes two types of crimping or pinout - "A" and "B". There is no significant difference between them, only the green and orange pairs change places. In Russia, the pinout of the "B" type is traditionally used. On the first two contacts, there is a white-orange and an orange wire, then a white-green one goes separately. Further, at 4 and 5, there is a blue pair, starting with the main color. Then, at 6 - green. 7.8 is given to white-brown and brown wires. To connect two devices of different rank to the network, for example, router and PC, it is necessary that the color scheme is observed at both ends of the cable. But in practice, you don't have to worry too much about colors. If you are sure that your cable will only be used at home by your two devices, then the color order according to the standard can be skipped. The main thing is to make them the same on both cable plugs.
Now about the crossovers. This type of crimp has been applied to connections between two peers, such as two PCs. The scheme is not symmetrical, that is, the order of colors is different on each side. However, there is a pattern that is easy to remember. We take the color arrangement for type "B" on one side, and on the other side we just completely change the orange and green pair. That's it, the crossover is ready. However, now such cables are used extremely rarely in the household segment. Each laptop is equipped with Wi-Fi, and it is easier to connect a stationary PC to a router using a ready-made cable, crimped using a direct method.
4-core pinout
Since in most cases the speed of local networks rarely exceeds 100 Mbit / s, in order to save money, they began to use 4 wires instead of 8 in the cable. There are only two pairs of colors - orange and blue. Orange is connected to the same contacts as in the classic type "B" - white-orange wire for 1 contact, orange for the second. On the third and sixth, white-blue and blue are connected. It is worth clarifying that in the scheme for 8 contacts there is a green pair in this place, so you can get confused.
How to crimp the cable correctly
For crimping the cable, a special tool is traditionally used - a crimper. Externally, it is a crimping pliers with special seats for connectors.
First, you need to strip the insulation from the UTP cable. Usually there is a special mechanism for this on the crimper. But you can also remove the insulation manually, with the help of improvised items. It is advisable to cut the wires so that they are the same size, about 1.5 cm. This, again, can be helped by a crimper, which is most often equipped with nippers. Exactly cut wires are placed in accordance with the required pinout scheme.
And then they are inserted into the connector, each in its place. Next, the device with tucked wires is inserted into the crimper socket and clamped with handles. During the crimping process, the metal pins of the connector will penetrate the wires, ensuring reliable contact. And the plastic latch will clamp the cable in the insulation, additionally securing it. The exact same operation must be repeated for the other end of the cable. That's all, the cable is crimped.