RJ11 | Technical features | instrumentic.info

What is what RJ11 ?
What is what RJ11 ?


The RJ11 standard is used for the phone. It is an international standard for connecting a device to the telecommunications network.

The information transmitted can be digital (DSL) or analog.

The telephone cable that usually arrives at the subscriber's home has 4 twisted pairs. Only one pair is used.
The two central contacts of the RJ11 socket, numbered 2 and 3, are used for the telephone line and the colours guide the user.

The continuous tension between the two links of the RJ11 connectors varies from country to country.
Each country has standardized its telephone sockets.

In Spain, a Spanish royal decree defines the use of RJ11 and RJ45 for users of the telephone network.
In Belgium, there are several types of RJ11 wiring :
2 links : blue, white - blue
4 bindings : blue, orange, orange - white, white - blue

The RJ25 connector is a modular Plug-type connector.
It is a phone connector that connects three lines. The RJ25 has six points and six contacts, the British equivalent is the standard BS 6312.

Connectors RJ11-RJ14-RJ25 :

Position pin RJ25 pin RJ14 pin RJ11 twisted pair R T France United States Germany Australia Netherlands colors RJ25
1 1 . . . T green white white or orange Purple Orange unreased green white
2 2 1 . 2 T orange white Black Green Red Orange orange white
3 3 2 1 1 R white blue Red White Blue Red white blue
4 3 3 2 1 T blue white Green Brown White Blue blue white
5 5 4 . 2 R white orange Yellow Yellow Black White white orange
6 6 . . . R white green blue or brown Grey Green Unused white green

pines RJ11
pines RJ11

RJ11 : the - T-

A telephone jack in T uses 8 standard connections, each corresponding to a bit of a different color : gray, white, blue, purple, Brown, yellow, orange.
However, a phone needs only two strands (usually grey and white) to operate, the others being mainly used for faxes.

Adapters can be used from one country to another according to the wiring.
The adapter converts and sends voice signals.

RJ11 connection
RJ11 connection

RJ11 : standards

Each country has standardized its phone shots.
There are about 44 different variations of standards and RJ11 Sockets. In Germany there is the TAE connector.

The RJ standards had many different configurations which have been abbreviated.
The terminology of today is : RJ11, RJ12 or for a plug 6-pin RJ14 and RJ45 for a 8-pole plug