All About STP Cable

We know that EMI (electromagnetic interference) is a disturbance in twisted pair cables. It affects the performance of an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction. The primary way to combat EMI in cables is through the use of shielding. The shielding can act on EMI in two ways: first, it can reflect the energy; second, it can prevent the noise and conduct it to ground. With the help of cable shielding, cables can be immune to the disturbance and keep a stable connection. And this article will present some knowledge about STP (shielded twisted pair) cable.

Overview of STP Cable

First of all, let’s have a quick overview of STP cable. As the name suggests, STP cable has a metal shield around each twisted pair which is composed of copper tape, a layer of conducting polymer or a braid (made of copper or aluminum mostly). And the shield can be applied to each pair of the cable or to all pairs together. Typically, STP cable is more expensive than UTP (unshielded twisted pair) cable. And due to the fragile and rigid shield of STP cable, it is necessary to pay much attention to the installation and maintenance of STP cable.

Types of Shields

There are mainly two types of shields: braided shield and foiled shield. Braided shield is made up of woven mesh of bare or tinned copper wires. The braid makes it much easier for cable termination by crimping or soldering when attaching a connector. However, braided shield does not provide 100% coverage. It typically provides 70% to 95% coverage according to the tightness of weave. But as a matter of fact, 70% coverage is always sufficient if cables are fixed. Another shielding is foiled shield. This type of shielding uses a thin layer of aluminum. Because it is thin, it is harder to work with, especially when applying a connector. It provides 100% coverage for the conductors it surrounds.

As copper has higher conductivity than aluminum and the braid has more bulk for conducting noise, the braid is more effective as a shield. If the environment is extremely noisy, a cable may use multiple layers of shielding with both the braided and foil designs. Here is figure of braided shield, foiled shield and braided/foiled shield, from which you can have a better understanding of inner structure of these three types of shields.

braided shield, foiled shield and braided foiled shield

Different Constructions of Shielding

When you plan to buy shielded 100m cat6 cable on store, you may have to make a choice between different construction of shielding. And here are are some commonly used shielding constructions:

1) Individual Shield

U/FTP is the typical individual shielding using aluminum foil. This kind of construction has one shield for each twisted pair or quad above the conductor and insulation. Individual shield especially protects neighboring pairs from crosstalk.

2) Overall Shield

F/UTP, S/UTP, and SF/UTP are overall shielding with different shield materials. Overall shield refers to the entire coverage around the whole cable. This type of shielding helps prevent EMI from entering or exiting the cable.

3) Individual and Overall Shield

F/FTP, S/FTP, and SF/FTP are individual and overall shield. This type of construction has both layers of shielding. And its immunity to EMI disturbance is greatly improved.

Meanings of the abbreviated letters:

U = unshielded

F = foiled shielding

S = braided shielding

TP = twisted pair

Applications

Power cables are constructed with shielding to be electromagnetic compatible (EMC) to minimize noise generation, which affects many other systems like radio and data communication. Bulk Ethernet cables are shielded to prevent the effects on the data transmitted from EMI. To further prevent cross talk and coupling, some bulk Ethernet cables are also paired and individually shielded. In some applications, such as those needing servo cables, double or even triple, shielding is required around individual conductors, around twisted pairs, and around the entire cable. By the way, if you use shielded cat6 cable for your network, the cat6 patch panel you choose must be shielded, too.

Conclusion

Adopting twisted pair cable shielding is an effective method to prevent EMI from interfering signal transmission. For the purpose of providing a reliable connection between electronic devices, choosing a proper shielded twisted pair cable is essential. FS.COM provides various types of shielded cables, such as FTP cat5e cable 305m, SFTP 100m cat6 cable, SFTP 1000 feet cat6 cable. If you want to know more details, please visit our site.

Distinguish A Good Ethernet Cable From A Bad One During the Selection

When you plan to deploy your network by using bulk Ethernet cable, you will find there are always various types of bulk Ethernet cables available on the market. And cables provided by different vendors vary in quality. There is no doubt that the quality of bulk Ethernet cable have an influence on the network performance. During the selection, how to distinguish a good Ethernet cable from a bad one is critical, which can also directly embody the ability of an engineer. Then, how to make sure that bulk Ethernet cables used in your network are of good quality? This article aims to share some tips with you.

Test the Data Transmission Rate

Testing the data transmission rate is one of the most effective methods to identify the quality of Ethernet cables. It is recommended that you connect two computers directly to do the test. But there may be some other factors that can affect the data transmission rate of the bulk Ethernet cable, such as the configuration of computer itself, the network card, RJ45 connector and so on. Hence, you should use machines with high configuration to reduce the external factors on the data transmission rate of the bulk Ethernet cable to a minimum. In this way, the result of test will be accurate.

Test the Flexibility

Ethernet cables of good quality are as flexible as possible, because the convenience of cabling has been taken into account at design time. It is easy to bend them in any ways and they are less likely to be broken easily. However, on the current market, there are some inferior bulk Ethernet cables which are mixed with other cheap metal components. The texture of such bulk Ethernet cables is no longer so soft and the data transmission rate becomes slower. In the process of cabling, if you bend the bulk Ethernet cable repeatedly, the copper wires inside the cable may be broken. While if the cable is too soft, then you should also note that it may be a fake and shoddy product.

Test the Flammability

In general, the materials composed of bulk Ethernet cable must be characterized with fire resistance, otherwise there is a fire, it will suffer heavy losses. Therefore, when choosing the bulk Ethernet cable, it is necessary to check the flammability of the cable jacket. Take cat6 cable 305m for example. In the test, you can use scissor to cut off about 2 cm length of its cable jacket, then burn it with a lighter. Under the condition of fire, cable jacket of good quality will gradually melt and deform after six seconds, with white smoke, but it will not burn itself up; while if the cable jacket is unable to resist the fire and burns up in less two seconds, with a large amount of black smoke, even though the cat6 cable 305m can provide 1000Mbps data transmission rate, you should give up the choice.

Test the Temperature Resistance

When carrying out cabling, bulk Ethernet cables are highly required to resist the external temperature changes. Not to say they can resist any change in the environment, at least those cables will not become soften under high temperature environment or frost crack under low temperature environment. For the sake of the performance of cable that will not be affected in the high temperature environment, cable jacket of good quality bulk Ethernet cable utilizes the material that can resist high temperature of up to about 50 degrees. And phenomenon like becoming soften or deformation will not occur. Take cat6 cable 305m from Fiberstore for example, its operation temperature range is from -10 degrees to 60 degrees and its installation temperature range is from 0 degree to 50 degrees. To do the test, you can place a short length of its cable jacket next to the stove for a while. And you will find that the cable jacket does not become softer than the normal one, it means that the quality of this cat5e cable 305m is good.

Observe the Identification

In the actual selection of Ethernet cables, sometimes due to the lack of test environment or conditions, you are not able to test the quality or material of the cable by the methods mentioned above. So what should you do at that time? You might as well observe the identification on the cable jacket. Normally, the regular brands of Ethernet cables have category identification and manufacture trademark on the cable jacket. If there is no identification on the cable jacket, you should be vigilant and try to create conditions to test the cable by following the above methods. Here is a figure of cat5e cable, from which we can clearly see the category identification and some other information about the cable.

cat5e cable

Conclusion

It is essential to select Ethernet cables of good quality for your network deployment, and that is the basic requirement to make your network achieve high performance level. As a result, when making a choice among various Ethernet cables, you have to observe carefully, compare more and test more. FS.COM provides good quality bulk Ethernet cables with many color and length options, such as gray cat6 cable 305m, yellow cat6 cable 100m, red cat6 cable 305m. If you want to know more details, you can visit our site.

Unsuitable Length of Ethernet Cable In Your Application?

Sometimes we may encounter the situation where the length of Ethernet cable bought in store is not suitable for the application. Is there an cost-effective way to solve this problem? Terminating the cable with RJ45 connector or using a RJ45 coupler to connect two cables by yourself can be a good option. This passage will introduce these two ways to solve such awkward problem.

Terminate Ethernet Cable With RJ45 Connector
Overview of RJ45 Connector

Before we come to the termination process, let’s have a brief overview of RJ45 connector. The letter “RJ” represents “registered jack”, which is a standardized physical network interface for connecting telecommunication or data equipment. RJ45 connector features eight positions and eight contact pins (8P8C). Material of the connector often uses plastic which makes it look transparent, thus the connector can also be called crystal connector (shown as the figure below). RJ45 connector is the most common twisted-pair connector for Ethernet cables.

RJ45 connector

Necessary Tools for Termination

Using special tools for termination is very important. You should not cut the cable with other unprofessional tools since it may cause damage and increase signal loss. Jacket cutter or wire stripper is needed to safely cut the jacket off and not hurt the inner wires. Cable crimping tool is necessary for crimping the RJ45 connector onto the wire to make a compact connection. Wire cutter is used to neatly cut the cable ends. Ethernet testing tool is important for the final check of the cable when termination is complete.

Steps of Termination Process

After everything is prepared, you can start terminating the Ethernet cable. Just follow the steps one by one, and the process can be done within several minutes.

Step one. Trim the end of the Ethernet cable with a crimping tool. Strip off about one inch of the jacket, leaving the twisted pairs outside.

Step two. Separate the 4 twisted wire pairs from each other, and then unwind each pair. Flatten the 8 individual wires as much as possible to make preparation for proper individual insertion into the connector.

Step three. Make clear on which standard you are based, then carefully place the wires in order according to that standard.

Step four. Hold the RJ45 connector and carefully insert the prepared wires into the connector, pushing them through the connector until the wire ends come out of the connector’s pin side. Make sure the color order is correct. If not, remove the wires from the connector and do it again.

Step five. Carefully cut the wire ends using crimping tool. Make sure the ends are as flush with the connector’s surface as possible to ensure a good plug-in connection.

If you have experience to install or maintain cables in LANs, you may know how important to terminate Cat5e, Cat6 or Cat6a bulk Ethernet cables with RJ45 connectors. Mastering this skill sometimes can save time as well as money in Ethernet cable installations.

Use a RJ45 Coupler

A RJ45 coupler, or inline coupler, is a small device with two female RJ45 jacks that joins two wires with Ethernet plugs together (shown as the figure below). Inline couplers do not provide any amplification or signal boost, and can cause attenuation and signal degradation unless they are of high quality. The primary use for a RJ45 coupler is to turn two short Ethernet computer networking cables into one long cable. When processing this, the RJ45 couplers need to be built to carry two cables with the same bandwidth in the network. This can be a convenient way to join two RJ45-terminated cables together to form one long cable.

RJ45 coupler

Conclusion

Learning the skill of Ethernet cable termination or connecting two cables with RJ45 couple efficiently solves the problem of unsuitable cable length. In this way, Ethernet cables can be more flexible to suit different applications. FS.COM provides the related copper products mentioned in the article, such as Cat5e cable 305m, Cat5e coupler, Cat6 coupler, RJ45 to RJ45 connector, etc. If you want to know more details, please visit our site or contact us via sales@fs.com.