A twisted pair cable consists of two conductors, typically copper. After twisting the wires together, they are usually insulated with a plastic jacket. In this cable, one wire transmits signals to the receiver, while the other serves as a ground reference. Notably, twisted pair cables are twisted in a helical pattern resembling the DNA molecule. The copper wires in a twisted-pair cable have a thickness of approximately 1mm. Furthermore, the twisting process aids in canceling out waves from different twists, significantly reducing the wire’s radiation.
Why Twist The Cable?
When two wires in a cable are arranged in parallel, the impact of unwanted signals on these wires differs due to their varying locations relative to the crosstalk source or noise. This results in a discrepancy in the signal received at the receiver. Therefore, a twisted pair cable maintains a balanced transmission of signals sent and received at the end-user.
Unshield Vs. Shielded Twisted Pair Cable
Shielded Twisted Pair Cable (STP) – This type of twisted pair cable features a metallic jacket, encapsulated by an additional plastic insulator. The metallic shield serves to protect against electromagnetic noise penetration. It also prevents crosstalk, a phenomenon where a wire within the cable inadvertently picks up signals transmitted by another wire. This effect can be noticed and sometimes disturbing during telephone conversations, such as hearing other conversations in the background during a call. Hence, the manufacturer incorporates the shield to eliminate any unwanted sounds.
Unshielded Twisted Pair Cable (UTP) – This type of twisted pair cable is widely used today, particularly in telephone systems. It is the most commonly utilized twisted pair cable in the communication industry. The UTP is favored for its capabilities in voice and data transmission. Constructed with two copper conductors, each wire is individually insulated with PVC, and the entire cable is further enclosed in a PVC jacket. When comparing UTP to STP, it is generally observed that UTP is more affordable, flexible, and features a simpler installation process.
Application Difference between Unshield Vs. Shielded Twisted Pair
There exists a distinction between shielded and unshielded twisted pair cables. The most apparent difference lies in their coverings: the shielded twisted pair cable features a metallic jacket surrounding the wires, followed by a plastic insulator, whereas the unshielded twisted pair cable is solely enclosed with a plastic cover (PVC).
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.
Conclusion
Communication is highly unlikely without the use of twisted pair cables. These cables have been in use for a long time and continue to evolve, enabling a wider range of applications such as data transmission. If you plan to install communication systems in your company or home, consider utilizing a high-quality twisted pair cable. For further information, please contact us.
