REFERENCE INFORMATION
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10. INFORMATION ON CABLES
10.1. "TWISTED PAIR" TYPE CABLE
"Twisted pair" type cable is one or several pairs of insulated wires twisted together (with a
small number of turns per unit length), covered with plastic.
Twisting is carried out in order to reduce electromagnetic interference from external sources
and mutual interference during signal transmission.
"Twisted pair" type cable is one of the components of structured cabling systems, is used in
telecommunications and computer networks.
The most common cables are four, two and one twisted pairs of wires.
10.2. RJ CONNECTORS
RJ (Registered Jack) - a standardized interface that describes the design of both parts of the
connector ("plug" and "socket") and their switching options.
There are standards RJ11, RJ14, RJ25, RJ45 and others.
Standard
Scheme
Purpose
RJ9
4P4C
Connecting the handsets to the telephone
RJ11
6P2C
Connecting 2-wire telephones
RJ12
6P6C
Connecting 6-wire telephones
RJ11
6P4C
Connecting 4-wire telephones
RJ21
50-pin
Connection of PBX or other telecommunication equipment
RJ25
6P6C
Connecting 6-wire telephones
RJ45S
8P4C with key Modem connecting
RJ45
8P8C
LAN connecting
RJ50
10P10C
UPS (American Power Conversion and Eaton Corporation)
xPyC designation:
"xP"- number of positions in the plug or in the socket
"yC"- number of contacts in the plug or in the socket
10.3. WIRING OF A CABLE CONSISTING OF FOUR TWISTED PAIRS OF WIRES
For Ethernet 10Base-T and 100Base-T, orange and green pairs are used. The remaining pairs
are reserved for the Gigabit Ethernet standard (1000Base-T). There are two options for wiring
568A or 568B. The most commonly used option is 568B.
