Twisted pair

This article is about the type of wiring. For the film, see Twisted Pair (film).
"Copper line" redirects here. For the San Diego Trolley line, see Copper Line (San Diego Trolley).

25-pair colour code chart

Twisted pair cabling is a type of communications cable in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. Compared to a single conductor or an untwisted balanced pair, a twisted pair reduces electromagnetic radiation from the pair and crosstalk between neighbouring pairs and improves rejection of external electromagnetic interference. It was invented by Alexander Graham Bell.[1]

For additional noise immunity, twisted-pair cabling may be shielded. Cable with shielding is known as shielded twisted pair (STP) and without as unshielded twisted pair (UTP).

  1. ^ Barnett, David; Groth, David; McBee, Jim (2004). Cabling: The Complete Guide to Network Wiring (3rd ed.). San Francisco: SYBEX. p. 11. ISBN 9780782143317.