8P8C: Difference between revisions
fix title |
fix naming, remove pedantic BS |
||
Line 1: | Line 1: | ||
{{Mergeto|Modular connector|Talk:Modular connector#Merger proposal|date=March 2009}} |
{{Mergeto|Modular connector|Talk:Modular connector#Merger proposal|date=March 2009}} |
||
[[File:Uncrimped rj-45 connector close-up.jpg|thumb|right|An |
[[File:Uncrimped rj-45 connector close-up.jpg|thumb|right|An modular plug before having been [[Crimp (joining)|crimped]] onto a cable]] |
||
[[File:Ethernet RJ45 connector p1160054.jpg|thumb|Connector and cable]] |
[[File:Ethernet RJ45 connector p1160054.jpg|thumb|Connector and cable]] |
||
''' |
'''''' plugs and sockets are most regularly used as an [[Ethernet]] connector.<ref>Under the same naming scheme, an 8P6C connector has eight positions, with six positions containing conductors, and a 6P6C connector has six positions, all containing conductors.</ref> connectors are typically used to [[Electrical termination|terminate]] [[twisted pair]] [[cable]]. |
||
has two paired components: the male plug and the female socket. Each has eight equally-spaced conducting channels. On the plug, these conductors are flat contacts positioned parallel with the connector body. Inside the socket, the conductors are suspended diagonally toward the insertion interface. When an plug is mated with an socket, the conductors meet and create an electrical connection. Spring tension in the socket's conductors ensure a good interface with the plug and allow for slight travel during insertion and removal. The connector is probably best known for its use in Ethernet; since around 2000, it has been used almost universally as the connector on Ethernet network cables, and has replaced many older connector types such as [[BNC Connector|BNC connectors]]. Older connectors have also been phased out as modern cables no longer have the high current and voltage requirements for which the bulkier connectors were designed. |
|||
== Standardization == |
|||
The shape and dimensions of an 8P8C modular connector are specified for U.S. telephone applications by the Administrative Council for Terminal Attachment (ACTA) in national standard [[ANSI]]/TIA-968-A. This standard does not use the short term 8P8C and covers more than just 8P8C modular connectors, but the 8P8C modular connector type is the eight position connector type described therein, with eight conductors installed. |
|||
For data communication applications ([[LAN]], [[structured cabling]]), International Standard IEC 60603 specifies in parts 7-1, 7-2, 7-4, 7-5, and 7-7 not only the same physical dimensions, but also high-frequency performance requirements for shielded and unshielded versions of this connector for frequencies up to 100, 250 and 600 [[MHz]], respectively. |
|||
== Wiring == |
== Wiring == |
||
Line 18: | Line 13: | ||
== Types == |
== Types == |
||
There are two types of |
There are two types of plugs, sockets, and diesets (used for [[crimping]]): Western Electric/Stewart Stamping (WE/SS) and Tyco/AMP. While both types look remarkably similar, they are mutually exclusive and cannot be interchanged. Tyco/AMP plugs are proprietary, and have smaller spacing between contacts than the WE/SS style. As a result, using a WE/SS crimp dieset on a Tyco/AMP plug will crush the top of the connector, and vice versa. While the WE/SS plug is more common than Tyco/AMP, it is still important to know what style is being used to avoid damaging the plug during crimping. |
||
WE/SS |
WE/SS plugs come in shielded and unshielded varieties, depending on the [[attenuation]] tolerance needed. All Tyco/AMP plugs include a metal ferrule, and so shielding comes standard. Shielded plugs are more expensive, but have a lower attenuation and can reduce [[signal noise]]. WE/SS plugs are available from a large number of manufacturers, whereas Tyco/AMP plugs are produced exclusively by [[Tyco Electronics]]. |
||
== Termination == |
== Termination == |
||
Termination of a cable with an |
Termination of a cable with an plug involves using a [[Pliers#Crimping pliers|hand crimper]] or crimp machine containing an die-set or an A67T standard die-set. An crimp die-set usually looks similar to an socket, except for the eight teeth lining the top portion of the die. When the tool is operated, the die compresses around the plug. As the die compresses, these teeth force the plug contacts down into the conductors of the cable being terminated, permanently attaching the plug to the cable. The crimper may also permanently deform part of the plug body in such a way that it grips the outer sheath of the cable. This helps to keep the plug securely fastened to the end of the cable. |
||
== Applications == |
== Applications == |
||
are commonly used in computer networking, where the plug on each end is an modular plug wired according to a TIA/EIA standard. These cables are typically used to connect [[Ethernet]] or [[Token Ring]] network interfaces. Most network communications today are carried over [[Category 5e]] or [[Category 6 cable|Category 6]] cable with an modular plug crimped on each end. |
|||
The |
The modular connector is also used for [[RS-232]] serial interfaces according to the [[Electronic Industries Alliance|EIA]]/TIA-561 standard[http://www.zytrax.com/tech/layer_1/cables/tech_rs232.htm#rj45]. This application is commonly used as a console interface on network equipment such as [[Network switch|switches]] and [[router]]s. Other applications include other [[computer network|networking]] services such as [[Integrated Services Digital Network|ISDN]] and [[t-carrier|T1]]. |
||
In floodwired <ref>'''floodwire''' is a chiefly British term for installing communications cables in a massive fashion in anticipation of their eventual use.</ref> environments the center (blue) pair is often used to carry [[telephony]] signals. Where so wired, the physical layout of the |
In floodwired <ref>'''floodwire''' is a chiefly British term for installing communications cables in a massive fashion in anticipation of their eventual use.</ref> environments the center (blue) pair is often used to carry [[telephony]] signals. Where so wired, the physical layout of the modular jack allows for the insertion of an [[RJ11, RJ14, RJ25|RJ11]] plug in the center of the socket, provided the RJ11 plug is wired in true compliance with the U.S. telephony standards (RJ11) using the center pair. The formal approach to connect telephony equipment is the insertion of a type-approved converter. |
||
The remaining (brown) pair is increasingly used for [[Power over Ethernet]] (PoE). Legacy equipment may use just this pair; this conflicts with other equipment as manufacturers used to [[short circuit]] unused pairs to reduce signal [[Crosstalk (electronics)|crosstalk]]. Some routers/bridges/switches can be powered by the unused 4 lines — blues (+) and browns (−) — to carry current to the unit. There is now a standardized scheme for [[Power over Ethernet]]. |
The remaining (brown) pair is increasingly used for [[Power over Ethernet]] (PoE). Legacy equipment may use just this pair; this conflicts with other equipment as manufacturers used to [[short circuit]] unused pairs to reduce signal [[Crosstalk (electronics)|crosstalk]]. Some routers/bridges/switches can be powered by the unused 4 lines — blues (+) and browns (−) — to carry current to the unit. There is now a standardized scheme for [[Power over Ethernet]]. |
||
Different manufacturers of |
Different manufacturers of modular jacks arrange for the pins of the modular connector socket to be linked to wire connectors (often IDC type terminals) that are in a different physical arrangement from that of other manufacturers: Thus, for example, if a technician is in the habit of connecting the white/orange wire to the "bottom right hand" IDC terminal, which links it to modular connector pin 1, in jacks made by other manufacturers this terminal may instead connect to modular connector pin 2 (or any other pin). |
||
== See also == |
== See also == |
||
* [[Computer network|Networking]] |
* [[Computer network|Networking]] |
||
* While the [[true RJ45]] uses a different 8P [[modular connector]] type, [[RJ48]], [[RJ49]], and [[RJ61]] do indeed use 8P8C modular sockets and plugs. |
|||
* [[RJ11]]: Interface used in many countries for regular [[Plain old telephone service|POTS]] (plain old telephone system) |
* [[RJ11]]: Interface used in many countries for regular [[Plain old telephone service|POTS]] (plain old telephone system) |
||
* See [[Registered jack]] for other, similar looking jacks, with which the 8P8C modular connector is likely (and often) confused |
* See [[Registered jack]] for other, similar looking jacks, with which the 8P8C modular connector is likely (and often) confused |
Revision as of 14:24, 27 August 2009
It has been suggested that this article be merged into Modular connector and Talk:Modular connector#Merger proposal. (Discuss) Proposed since March 2009. |
RJ-45 plugs and sockets are most regularly used as an Ethernet connector.[1] RJ-45 connectors are typically used to terminate twisted pair cable.
RJ-45 has two paired components: the male plug and the female socket. Each has eight equally-spaced conducting channels. On the plug, these conductors are flat contacts positioned parallel with the connector body. Inside the socket, the conductors are suspended diagonally toward the insertion interface. When an RJ-45 plug is mated with an RJ-45 socket, the conductors meet and create an electrical connection. Spring tension in the socket's conductors ensure a good interface with the plug and allow for slight travel during insertion and removal. The RJ-45 connector is probably best known for its use in Ethernet; since around 2000, it has been used almost universally as the connector on Ethernet network cables, and has replaced many older connector types such as BNC connectors. Older connectors have also been phased out as modern cables no longer have the high current and voltage requirements for which the bulkier connectors were designed.
Wiring
It is frequently terminated using the T568A or T568B pin/pair assignments that are defined in TIA/EIA-568-B. A cable that is wired as T568A at one end and T568B at the other (Tx and Rx pairs reversed) is a "crossover" cable. Before the widespread acceptance of auto-MDI/MDIX capabilities a crossover cable was needed to interconnect similar network equipment (such as hubs to hubs). Crossover cables are still used today to connect two computers together without a switch or hub. A cable wired the same at both ends is called a "patch" or "straight-through" cable, because no pin/pair assignments are swapped.
Types
There are two types of RJ-45 plugs, sockets, and diesets (used for crimping): Western Electric/Stewart Stamping (WE/SS) and Tyco/AMP. While both types look remarkably similar, they are mutually exclusive and cannot be interchanged. Tyco/AMP RJ-45 plugs are proprietary, and have smaller spacing between contacts than the WE/SS style. As a result, using a WE/SS RJ-45 crimp dieset on a Tyco/AMP RJ-45 plug will crush the top of the connector, and vice versa. While the WE/SS RJ-45 plug is more common than Tyco/AMP, it is still important to know what style is being used to avoid damaging the plug during crimping.
WE/SS RJ-45 plugs come in shielded and unshielded varieties, depending on the attenuation tolerance needed. All Tyco/AMP RJ-45 plugs include a metal ferrule, and so shielding comes standard. Shielded plugs are more expensive, but have a lower attenuation and can reduce signal noise. WE/SS plugs are available from a large number of manufacturers, whereas Tyco/AMP plugs are produced exclusively by Tyco Electronics.
Termination
Termination of a cable with an RJ-45 plug involves using a hand crimper or crimp machine containing an RJ-45 die-set or an A67T standard die-set. An RJ-45 crimp die-set usually looks similar to an RJ-45 socket, except for the eight teeth lining the top portion of the die. When the tool is operated, the die compresses around the RJ-45 plug. As the die compresses, these teeth force the plug contacts down into the conductors of the cable being terminated, permanently attaching the plug to the cable. The crimper may also permanently deform part of the plug body in such a way that it grips the outer sheath of the cable. This helps to keep the plug securely fastened to the end of the cable.
Applications
RJ-45 are commonly used in computer networking, where the plug on each end is an RJ-45 modular plug wired according to a TIA/EIA standard. These cables are typically used to connect Ethernet or Token Ring network interfaces. Most network communications today are carried over Category 5e or Category 6 cable with an RJ-45 modular plug crimped on each end.
The RJ-45 modular connector is also used for RS-232 serial interfaces according to the EIA/TIA-561 standard[1]. This application is commonly used as a console interface on network equipment such as switches and routers. Other applications include other networking services such as ISDN and T1.
In floodwired [2] environments the center (blue) pair is often used to carry telephony signals. Where so wired, the physical layout of the RJ-45 modular jack allows for the insertion of an RJ11 plug in the center of the socket, provided the RJ11 plug is wired in true compliance with the U.S. telephony standards (RJ11) using the center pair. The formal approach to connect telephony equipment is the insertion of a type-approved converter.
The remaining (brown) pair is increasingly used for Power over Ethernet (PoE). Legacy equipment may use just this pair; this conflicts with other equipment as manufacturers used to short circuit unused pairs to reduce signal crosstalk. Some routers/bridges/switches can be powered by the unused 4 lines — blues (+) and browns (−) — to carry current to the unit. There is now a standardized scheme for Power over Ethernet.
Different manufacturers of RJ-45 modular jacks arrange for the pins of the RJ-45 modular connector socket to be linked to wire connectors (often IDC type terminals) that are in a different physical arrangement from that of other manufacturers: Thus, for example, if a technician is in the habit of connecting the white/orange wire to the "bottom right hand" IDC terminal, which links it to RJ-45 modular connector pin 1, in jacks made by other manufacturers this terminal may instead connect to RJ-45 modular connector pin 2 (or any other pin).
See also
- Networking
- RJ11: Interface used in many countries for regular POTS (plain old telephone system)
- See Registered jack for other, similar looking jacks, with which the 8P8C modular connector is likely (and often) confused
Notes
- ^ Under the same naming scheme, an 8P6C connector has eight positions, with six positions containing conductors, and a 6P6C connector has six positions, all containing conductors.
- ^ floodwire is a chiefly British term for installing communications cables in a massive fashion in anticipation of their eventual use.
References
- ANSI/TIA-968-A: Telephone terminal equipment – Technical requirements for connection of terminal equipment to the telephone network
- IEC 60603-7-1: Connectors for electronic equipment — Part 7-1: Detail specification for 8-way, shielded free and fixed connectors with common mating features, with assessed quality
- IEC 60603-7-2: Connectors for electronic equipment — Part 7-2: Detail specification for 8-way, unshielded, free and fixed connectors, for data transmissions with frequencies up to 100 MHz
- IEC 60603-7-4: Connectors for electronic equipment — Part 7-4: Detail specification for 8-way, unshielded, free and fixed connectors, for data transmissions with frequencies up to 250 MHz
- IEC 60603-7-5: Connectors for electronic equipment — Part 7-5: Detail specification for 8-way, shielded, free and fixed connectors, for data transmissions with frequencies up to 250 MHz
- IEC 60603-7-7: Connectors for electronic equipment — Part 7-7: Detail specification for 8-way, shielded, free and fixed connectors, for data transmissions with frequencies up to 600 MHz
- ISO/IEC 8877, EN 28877: Information Technology - Telecommunications and Information Exchange between Systems - Interface Connector and Contact Assignments for ISDN Basic Access Interface Located at Reference Points S and T
External links
- How to Make a Network Cable
- How to wire a 10BaseT or 100BaseT connector with Category 5 cable and 8P8C modular connectors
- Step by Step Instructions on How to Punch Down Category 5e Cable to a RJ45
- How to create your own Ethernet Cables
- TIA-968-A — Contains dimensions for sockets and plugs.
- Catalog page showing the difference between solid and stranded contacts
- Diagram of RJ45S showing the difference between an 8P8C and a true RJ45 8-position keyed connector.
- USOC RJ45S with programming resistor has a different shape than the computer "RJ45".
- RJ45 Pinouts and cables schematics (including network cables)
- RJ45 Interactive Example