A twisted pairs cable is a cable that contains one or more pairs of copper wires. These wires are insulated and twisted to reduce some significant physical transmission issues. When an electric current passes over a wire, it creates electromagnetic interference (EMI) that interferes with electrical signals in nearby wires, including wires in the same cable. EMI between wire pairs in the same cable is called crosstalk. Twisting the wire pairs reduces cross-talk.
How does a twisted pairs cable work
A twisted pairs cable contains copper wires. Copper wires carry electrical signals. To use a copper wire to transmit data, the end devices convert the data into electrical signals. The sender device converts data into electric signals. The receiver device converts electric signals into data. Converting data into electric signals is called encoding, whereas converting electric signals into data is called decoding.
Electricity flows in a loop. A loop needs two wires. Generally, a twisted pairs cable contains eight wires in four pairs. From these pairs, two pairs are used to create electric loops. The remaining two pairs are used to reduce cross-talk and other interferences.
Types of twisted pairs cable
There are two types of twisted pairs cable: shielded twisted pairs (STP) cable and unshielded twisted pairs (UTP) cable. The following table lists the main differences between STP and UTP cables.
| UTP | STP |
| It contains only an outer layer of plastic. It does not wrap each pair individually inside the cable. | Along with the outer plastic layer, it also wraps each pair with a mesh or foil inside the cable. |
| It is cheaper than the STP cable. | It is costlier than the UTP cable. |
| It has higher cross-talk than the STP cable. | It has lower cross-talk than the UTP cable. |
| It generates more EMI than the STP cable. | It generates less EMI than the UTP cable. |
| It provides less speed than the UTP cable. | It provides a higher speed than the UTP cable. |
| It is easy to install and manage. | It is hard to install and manage. |
| It is mainly used in homes or small offices. | It is mainly used in corporate offices. |
| It is suitable only for short distances. | It is suitable for both short and long distances. |
Characteristics and functions of a twisted pairs cable
- A twisted pairs cable uses twisted pairs of copper wires.
- It transmits data in the form of electric signals.
- It is mainly used in the IT and telecom sectors.
- It is suitable for data and voice transmission.
- It is used to build a LAN network.
- It provides higher data transfer speed and costs lesser money than other available media.