Upon opening a telephone wall socket or cable, you will find various coloured wiring. Identifying the different types of wire appears it would be a simple task, but dissimilar wiring standards and multiple lines can complicate the process. A telephone socket may use four solid colours that prove relatively easy to differentiate, while others have less easily distinguished wires with stripes. The type of wire may differ depending upon whether a specific colour acts as the stripe or the main--or primary--colour.
A telephone socket typically contains at least two sets of wires. Every separate phone line/number uses two strands of wire to carry the audio, ring signals and power, according to AbleComm. Some sockets have more wires--and colours--to accommodate additional lines. In each set of two wires, one is termed the "ring" while the other is known as the "tip." Many telephone jacks have green and black "tip" wiring, with red and yellow "ring" wires, according to HomePhoneWiring.com. The green and red wires go together and connect to the first line.
The telephone socket may use a different set of colours or have additional colours for three to four lines. For example, AbleComm says one pair of wires might be orange and white while the other set is blue and white. Others use stripes to differentiate "ring" and "tip" wiring, such as a blue wire matched with a blue-striped white wire. An orange-striped white wire is a "tip" and a white-striped blue wire or a white-striped orange wire is a "ring," HomePhoneWiring.com states.
A telephone socket containing many lines may resort to using additional colours like purple, grey or brown to differentiate the wiring. HomePhoneWiring.com indicates that up to 25 sets--50 wires total--may be identified using different colour combinations, although most socket types contain no more than four. In some cases, different groups of telephone socket wiring colours exist within the same building, especially if the cables were installed years apart.
Telephone socket wiring provides power to operate phones which do not connect to separate AC power sources. The yellow and black (or white/orange and orange) wires deliver a small amount of electricity, according to Tech-FAQ.com. The same proves true for any other set of two matching wires, like red and green. The electrical current is supplied at approximately 5 volts. This voltage level equals slightly more than that produced by three "AA" batteries.