The types and purpose of patch cords
Currently, no structured cabling system (SCS) it is impossible to imagine any enterprise, shop or apartment. Patch cords are one of the most common elements of the SCS. In fact it is a piece of stranded wire, crimped on both ends with connectors. Often, the patch cords are called patch cords.
Their main task is to connect different devices. Patch cords for the convenience of users made in different colors. Use patch cords of different colors helps reduce the time localization problem area of structured cabling network and troubleshoot problems.
What is patch cord
Patch cord (patch cord) is an electrical or optical cable to connect or interconnect electrical devices. They vary in type and length. Both sides of the cable must be crimped plug-in connectors. These specific connectors are called connectors.
To join the two workstations are often used crossover. He also is a patch cord, but with cross-connection circuit. Another name of this connection is a «jumper connection».
Patch cords can be any size, but must not exceed the length of 5 m according to the standard ANSI EIA TIA 568B.1. For open offices allowed patch cords of greater length.
Scope
Most often, the patch cord used to connect workstations to SCS, to connect network and server equipment.
The basis of the stranded wires is the main advantage of patch cord in comparison with the conventional UTP cable solid wire. Improve such parameters of the cable, as the resistance to fracture and its flexibility. At the same time, flexible patch cord results in a deterioration of basic electrical parameters, which in the end affects the speed of information transfer.
Depending on the application area there are the following types of patch cords: for telephone networks, the switching (router, switch, and other similar equipment) and fiber optic (fiber optic cable, terminated both ends optical connectors).
What are
The classification of patch cords can be performed according to various criteria and parameters.
Most often, patch cords klassificeret:
- size. Standard sizes: 0.5 m, 1m, 1.5 m, 2m, 4m, 5m Custom sizes can be made to order;
- the type of connector. Pass patch cords to the ends of different connectors, connecting the same;
- the type of connector. Often use RJ-45 connectors and RJ-12. Less common connector 110-type;
- the presence of shielding. Distinguish shielded (FTP) and unshielded (UTP).
Length and color are selected based on personal preference. It is important to know that the lengths of patch cords and trunk lines must be summed, and the total length should comply with existing standards structured cable network. Now the maximum segment length SKS should not exceed 100 m.
Between the cable and the patch cord, there are differences. Cable fixed still and remain motionless for a long period, the patch cords, on the contrary, is always a certain mechanical loading, can happen to them stranding. If treated with a patch cord, the cable it may be damaged, which greatly reduces his options. Multi-strand patch cords are more adapted to constant stress.
The use of shielding for patch cord is not a mandatory necessity. Screen protection allows to protect the cable from external electromagnetic waves. Grounding is mandatory application FTP patch cords.
In computer networks often use molded patch cords. Their main difference is in the plastic cap. It can be soldered directly to the cable, unlike the conventional in which he can freely move along the entire length. Molded patch cord can only be factory production, it is impossible to make at home.
In the limited space on the network objects convenient to use the designs of flat patch cords.
Video: Crimping UTP cable 5
Category patch cords
Every factory patch cord passes the certification process, the results of which is assigned a certain category. The category determines where it can be used in the patch cord, what is the data transfer rate it can support.
Today are mostly used shielded patch cords category 5e. They are distinguished by providing quality connections in structured cabling systems of any size. They are great to support data transmission speed up to 100 Mbit/sec, which is the minimum required at present.
For organizations Gigabit LAN network patch cord category 5 is not suitable, necessary patch cord category 6. It is based on the cable, each of the eight lived which consists of seven copper wires, insulated in durable polyethylene.Patch cord category 6 has a slightly larger outer diameter of the cable (6.2 mm) that you need to consider when laying.
Patch cords category 7 is designed to transmit data at speeds up to 10 GB/s. In such patch cords shielded cable is not only whole, but also each pair is shielded separately.
Key features
Each patch cord has a number of characteristics. The main concern of the sheath material, diameter and type of conductor, as well as the average velocity of propagation of the signal. In addition to basic, release gear, geometric, and mechanical-climatic characteristics.
To consider the transfer characteristics of damping coefficient and coefficient of chromatic dispersion at the reference wavelength.
The thickness of the sheath nominal cable diameter and nominal mass are the basic geometric parameters of the patch cord.
Among the mechanical-climatic characteristics distinguish the bending radius allowable tensile and crushing force, resistance to torsions and shocks, temperature of operation and installation.
The values of these characteristics depend on the specific manufacturer’s patch cords.
Wiring diagram
There are two basic connection schemes: direct and cross.
Direct connection scheme used to connect the workstations with the switches, and to connect switches to each other through the Uplink port.
Cross or cross connection scheme required to directly connect two workstations. Also using cross-schema is a network connection between hub without using the Uplink port . Below is a diagram of the cable connections. The numbering of the contacts on the connector from left to right, if you keep up the connector contacts and the cable to itself.
Video wiring.
Cross-wiring
Contact
Wire color
Contact
Contact
Wire color
Contact
1
white-orange
1
1
white-orange
3
2
orange
2
2
orange
6
3
white-green
3
3
white-green
1
6
green
6
6
green
2
5
white-blue
5
5
white-blue
5
4
blue
4
4
blue
4
7
white-brown
7
7
white-brown
7
8
brown
8
8
brown
8
Why the factory patch-cord?
Manufacturer of patch cord with their hands quite simple, and the cost will be significantly less than factory. Weird. Isn’t it? Why the factory patch cords are manufactured in the millions are much higher homemade patch-cord?
The difference lies in the fact that the manufacturer is testing for compliance with the defined parameters of each patch cord and the results of verification zabrakovanie of its products. Buying a factory patch cord, the customer pays for the assurance of flawless functioning of the SKS.
In SKS highlights the loss of its parameters is the joints. And each patch cord is affected by two connections. Incorrect wiring wire can spoil the characteristics of the whole network. Perhaps with poor swage the occurrence of crosstalk in it. After eight unbraided wires of the twisted pair act as a parallel antennas, whereby each pair creates its own interference and receives the interference of the adjacent pairs.
Of course, the case of force majeure when it is necessary to promptly connect a new device to the local network, or to replace a damaged cable. The only way out of these situations will be making a temporary patch cord with their hands.
But in any case it is not recommended to use a homemade cable for the connection of active network and server equipment. It is foolish to spend huge sums certified by SCS to save on the little things.
It is therefore necessary to make a choice in favor of factory patch cords. Moreover, it is very important to carefully study all manufacturers of these products and to choose the manufacturer with the best quality.
Thus, the patch cords play a significant role in ensuring the reliability and performance of the SCS.
Experience shows that the use of patch cords is low quality (especially homemade), despite the savings at the stage of creating the local network in the future in the course of its operation leads to significant additional costs. Due to the use of low-quality patch cords are often failures and downtime. And one of the main qualities SKS reliability. Therefore, it is recommended to use patch cords from trusted manufacturers.