What Is A Twisted Pair Cable

A twisted pair cable is made from two conductors, an example being copper. The cable is normally insulated with a plastic jacket once the wires are twisted together. One wire in the cable carries signals to the receiver while the other works as a ground reference. You will realize that the twisted pair cables are twisted in a helical form that resembles the DNA molecule. The twisted-pair cable’s copper wires have a thickness of approximately 1mm. Also, the twisting process helps cancel out the waves from different twists ensuring the wire’s radiation is immensely reduced.

Why Twist The Cable?

When two wires in a cable are parallel, the unwanted signals’ effect on the wires is different. This happens since both have different locations relative to the crosstalk source or noise. It causes a difference in the signal received at the receiver. So, when a twisted pair cable maintains a balance in the signals sent and received at the end-user.

Unshield Vs. Shielded Twisted Pair Cable

Shield Vs. Unshielded Twisted Pair Cable

Shielded Twisted Pair Cable (STP) – This twisted pair cable has a metallic jacket plus another plastic insulator. The metallic shield or jacket helps to prevent any electromagnetic noise from penetrating. Also, it prevents crosstalk, an effect whereby a wire picks up signals transmitted through another wire within the cable. This is an effect you are likely to realize and sometimes feel during telephone conversations. You might hear various other conversations during a call in the background. Therefore, the purpose of the manufacturer instilling the shield is to prevent any unwanted sounds.

Unshielded Twisted Pair Cable (UTP) – unshielded twisted pair cable is used today due to its use in telephone systems. It’s the most commonly used twisted pair cable in the communication sector. The UTP is a type of twisted-pair cable preferred for its voice and data transmission abilities. The cable has two conductors, all made from copper. Each wire is shielded with a PVC insulator, and the cable is covered entirely with a jacket also made of a PVC insulator. Comparing UTP and STP, you will likely identify that UTP is cheaper, flexible, and has an easy installation procedure.

Application Difference between Unshield Vs. Shielded Twisted Pair

There is a difference between the shielded and unshielded twisted pair. The general and visible difference you can identify is that; the shielded twisted pair cable has a metallic jacket covering the wires and then a plastic insulator on top, while the unshielded twisted pair cable is only covered with a plastic cover (PVC).

difference between shielded and unshielded twisted pair cable

When it comes to their applications;

Unshielded twisted pair cable

  • A basic unshielded twisted pair cable is used in telephone systems and is preferred for fine voice communication. Also, it transmits data communication but at a very low speed (4Mbps).
  • The twisted-pair cable can carry data up to 10Mbps if made from a minimum of three twists for every foot. This is making the telephone service companies use the cable more regularly.
  • Adding the twists per foot can improve the cable services to handle up to 100Mbps.

Shielded twisted pair cable

  • This type of twisted pair cable is applicable in telephone lines to transmit voice and data, similar to UTP.
  • However, due to its high cost, it is not commonly used like the UTP.


Communication is likely not to happen without the twisted pair cable. The cable has been in use ever since, and it’s evolving to allow more applications like carrying data. If you intend to install communication systems in your company or home, consider using a quality twisted pair cable. Contact us for more information.

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