Cat 5 Cable

In twisted pair cabling, wires are twisted together to cancel the electromagnetic interference from outside sources, thus preventing the crosstalk within the wires. The interference is reduced by twisting because the loop area between the wires is decreased. Two wires generally carry opposite and equal signals which cancel each other because of the same electromagnetic interference.

Twisting rate, i.e. twists per meter, distinguishes the given cable from other cables. The attenuation of crosstalk increases with the number of twists. In case of telephone wiring, one wire of a single pair may be very close to a source of electromagnetic radiation and, thus, experience electromagnetic interference. Twisting the wire can reduces this interference.

Types of twisted pair cable:

1. Unshielded Twisted Pair (UTP) Cable

The twisted pair cables were first of all used in the telephone systems by Bell in the year 1881 and since than the twisted pair cables are used, or some similar open wire, to reduce interference. Lots of conductors of twisted pairs in the world are used for outdoor purpose. They belong to telephone companies who install them for the purpose of voice transmission.

These UTP cables are not covered by any shield. This results in lots of flexibility. They can be bent according to the need. The UTP cables are normally used in Ethernet networks and telephone cabling. For indoor telephone wiring these are grouped together into a set of 25 pairs. UTP cables are used for networking especially Ethernet networking and that is why they are also called Ethernet cables.

2. Shielded Twisted Pair Cable

These shielded twisted pairs are normally used for business purposes and are a type of copper wiring. An outer covering is added to normal twisted pair wires in order to shield them from electromagnetic interference.

These are normal copper wires used both for home and business purposes. In order to prevent crosstalk or electromagnetic interference between the wires, the insulated copper wires are twisted. Both the wires are required for signal transmission. In places where multiple connections are required, the installation is done with two or more pairs in the same cable. They are normally for business purposes. It has now become convenient to attach some extra line to an already existing connection. Generally twisted pair is cabling is used for home purpose. But at times they are also used to establish a LAN network because of their low cost.