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How To Tell If An Ethernet Cable Is Shielded (5 Different Ways)

When you stuff your home or office with appliances and cables, you’ll experience problems with flux. Not only does this electromagnetic radiation damage the appliances, but it can pose some health risks too. Shielding your Ethernet cables reduces the radiation and prevents crosstalk between them.

Ethernet cables help to provide internet to several devices on a local network.
The shielded twisted pair (STP) cables are interwoven wires, wrapped in foil, and then wrapped again for double protection. The unshielded twisted pair UTP cables have a pair of wires twisted together but not covered with foil.

It’s quite easy to confuse the two cables. The following are some of the ways to determine whether your Ethernet cable is shielded.

Related: Do I Need Shielded Ethernet Cable For Home? (What You Should Know)

How To Tell If Ethernet Cable Is Shielded

how to tell if ethernet cable is shielded

1. Looking At The Number Of Twisted Pairs

Increasing the number of twists per inch can significantly enhance the safety of Ethernet cables. Shielded cables have pairs of conductors that diminish the interference and improve the performance of your Ethernet connections. You will either find the foil shielded pair (FTP) or the unshielded twisted pair (UTP).

The shielded cables are categorized depending on their thickness. CAT3, CAT4, and CAT5 Ethernet cables have four pairs of twisted copper wires. CAT5 cables have more twists per inch than the rest and can run at greater lengths and higher speeds.

The twist in each pair of cables helps to cancel out the interference. The CAT5 wire provides significant crosstalk protection, enabling it to support network speeds of up to 1Gbps.

The shielded CAT 6 cables come in four pairs with eight different colors. The cables have four pairs of twisted wires and the RJ connector, commonly used in coaxial and fiber optic connections. Since the crosstalk between CAT 6 conductors can reach 250MHZ, you need to keep them 16 inches apart and cross at right angles.

2. By Using A Multimeter

With a multimeter, you can determine various electrical values such as voltage, current, and resistance. Unshielded cables carry roughly between 1.6 amps to 2.3 amps based on the quality of the cable.

The maximum capacity for shielded cables is 2.5 amperes and 25 volts. The relationship between the cross-sectional area of the cables and the resistance is inversely proportional. Since the shielded wires have more amperage and low resistance, they can connect to more electrical devices.

3. By Cutting The Wire And Inspecting It

Once you cut through the outer insulation foil, you will find the four pairs of twisted cables. Each of the eight wires is insulated with foil. Then, two pairs of wires are insulated for extra protection.

There is an overall foil shield for the four pairs underneath the main foil. The cables have a ninth wire for grounding the electrical currents and protecting your appliances from power surges.

Unshielded cables vary in thickness as they may contain from 2 to 4 twisted pairs. Since the wires don’t have an outer shield, they are vulnerable to electrical interference. A polyethylene jacket protects the four twisted wires.

4. Check For Markings On The Cable

Cable labeling is essential as it can save you time when troubleshooting. Purchasing labeled cables will also save you time during installation.

The unshielded cables have a mark that indicates the wire size. It’s usually marked 12 or 12-gauge, followed by AWG for American Wire Gauge. There’s another mark that shows the number of wires, either 2 or 4.

The insulated wires are stuck together and don’t contain a ground wire. The mark appears on the outer jacket for easy identification.

The shielded cables are identified according to their categories, showing the thickness and length. For example, FTP CAT 6, 1000 ft represents an underground data cable resistant to water and UV damage.

It’s easy to confuse the telephone and internet cables. Marked cables can help you to avoid confusion down the road. Since the labels conform to the standard codes, everyone will have an easy time when handling the various connections.

5. Look At The RJ Connector

One of the main advantages of an RJ$45 connector is the ease with which you plug and remove it. It has a resilient clip at the back of the jack that adjusts accordingly when the jack is firmly in place. These jacks can be plugged multiple times without the risk of degradation, making them ideal for both shielded and unshielded Ethernet cables.

The RJ45 connector for unshielded cables is a physical connector for Ethernet networking. It’s a modular plug jack that contains the unshielded twisted cable (UTP), plug jack at both ends of the cable, and a cap.

The smart feed CAT5 shielded connector is engineered for use with an outdoor/indoor Ethernet cable. The Rj45 connector has three-prong gold-plated contacts that connect to the copper core.

It also comes with dual grounding with an external drain wire tab and an internal metal connector. It comes with polyethylene shielding that protects all cables in a densely wired environment.

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