What is a shielded network cable? In this article, you will learn about its structure and usage.

1. Difference between shielded network cable and unshielded network cable

Let's see what they look like.

The category 6 shielded wires mentioned above are single layer shielded.

From outside, you can see that inside of shielded network cable has aluminum foil or copper braided mesh for shielding.

Single or multi-layer shielding is available, as well as individual shielding.

Twisted pair with double shield, each twisted pair has a shield layer and outer layer also has one or more shield layers

A shielded network cable refers to a network cable with a shield layer inside, and shield layer refers to aluminum foil and woven mesh. The shielding layer of single shielded network cable has only one layer of aluminum foil paper, and double shielded network cable is wrapped with a layer of aluminum foil on outside of twisted wire and has a layer of metal braided mesh. Shielded network cable and unshielded network cable differ depending on environment in which they are used. Double-shielded network cables are mainly used in heavy interference environments, while unshielded network cables are used in general daily network environments.

Secondly, using a shielded network cable

Due to structure of a shielded network cable, its use is determined. Shielding should reduce influence of external electromagnetic interference on data transmission. It is often used in a computer room environment with complex electromagnetic environment and strong interference.

Interference may cause intermittent or even intermittent signal transmission over network cable, and signal may not be transmitted normally. The use of shielded network cables can resist interference well, maintain normal transmission, and have good privacy characteristics. Shielded wiring shield structure has inherent advantages in reducing mutual interference between cables. It can not only shield external electromagnetic signals, but also aluminum foil. , It blocks electromagnetic leakage of cable itself, does not emit interference affecting operation of other cables, and can prevent information from being eavesdropped.

A shielded network cable will have a copper wire, that is, a ground wire. A shielded RJ45 jack can be used, and one end of ground wire is grounded when used. The ground wire can better shield external signal. Shielded network cables need good grounding, and shielded lines can well reduce influence of strong interference on network signals. Do not use shielded network cables unnecessarily, because wiring requirements of shielded network cables are high, not only accessories in system must be shielded and must have good grounding to play a role. If grounding is bad, effect will be very bad.

What is single-shielded Category 5e network cable?

Single-shielded Category 5e network cables require all shielding devices in entire system, including network cables, modules, crystal heads, etc. Compared to unshielded Category 5e network cables, except for twisted pairs and filler cables, the outer layer is wrapped aluminum foil to reduce radiation. The use environment, such as strong electromagnetic radiation and strict data transmission requirements, can use CAT5E single-shielded network cable, which is trustworthy.

What is a dual-shielded Cat5e network cable?

The double-shielded cable is wrapped with a layer of aluminum foil on outside of twisted wire, and has a layer of metal braided mesh, which is suitable for high-speed network and high-security transmission to reduce radiation. This kind of shielded wire is suitable for high frequency sine wave application and is used in wiring between user's communication terminal and switchboard of residential integrated wiring system.

Third, difference between STP, SFTP, UTP, FTP, and ASTP

STP: independent shielded twisted pairs with addition of an aluminum foil layer on outside of main wires, each pair of wires has an aluminum foil shield layer, purpose of which is to reduce signal attenuation. In addition, for every 4 pairs of wires, there is a metal-braided shield layer, which complies with structural standard of seven types of network cables. It is suitable for high-speed network and high-security transmission, can support future application upgrades, can unify wiring platform, and transmit multiple media information together.

SFTP: double shielded twisted pair, addition of STP aluminum foil braided mesh, usually aluminum-magnesium wire, braided mesh, tinned copper mesh, outer layer is PVC outer sheath, in general It is said that there are two shielding layers and there must be insulation between two shielding layers. Its advantage is to effectively reduce environmental magnetic field and signal interference, and internal signal attenuation is low. The disadvantage is its low flexibility and high cost. This type of anti-interference wire with high privacy is suitable for professional wiring projects in special environments.

UTP: unshielded twisted pair, which is currently most widely used wire for electrical wiring systems in general market. It is used for common network applications with bandwidth below 250 MHz and no special performance requirements. The performance is adequate, price is cheap, and construction and maintenance are convenient. However, highest performance limit of this type is supported only by a cabling system of six types of network cables.

FTP: aluminum foil shielded twisted pair cable, which has the advantages of wide bandwidth, certain noise immunity, low signal attenuation, low smoke, halogen-free processing and environmental protection.

ASTP: Armored Twisted Pair Shielded Network Cable (Cable) is a special double-shielded network cable. In use, both ends of steel tape armor layer are grounded and one end of innermost shield is grounded. In addition to double shielded wire effect, it has high strength and can be used in wiring systems with frequent rodent infestation or explosion protection requirements. Generally, shielded wires are more expensive in cost and installation than unshielded wires, and their bending performance is slightly worse. However, it is suitable for some special environments and built-in shielded system wiring. You can make a reasonable choice after understanding your own situation in order to optimize cost and effect of wiring.

Addition:

The shielded network cable must use network cable connector with a metal shield cover, and shield layer inside wire must be tightly connected to shield cover, which is difficult for users using ordinary network cable pliers for manual crimping. terminal.

Crystal head with shield

Second, for a shielded network cable to function, you must ensure that all equipment used supports shielding and has proper grounding measures. If device does not support shielding, shielding network cable is useless. If grounding measures are not properly implemented, ability of network cable to withstand interference will be significantly reduced or even worse than that of an unshielded network cable of same type. .