Cable Shielding Deciphered

June 1, 2017 at 8:00 AM

 

It’s no surprise that shielded cables are a hot topic, they can improve performance and are available in Cat5e, Cat6 and Cat6a and Cat7 versions. In past blog posts, we’ve talked about the advantages of shielded cables and how they protect from EMI/RFI and alien crosstalk (AXT). We’ve dug deeper to explore the different types of shielded cables and their benefits. We’ve even shown how to make your own shielded cable. Now, we’re going to take a closer look at the acronyms used to designate the different types of cable shielding and how to decipher them.

 

Cable shielding, also called screening, can be made of a metallic braid, or metallic or polyester foil. The shielding is either wrapped around all 4 pairs of twisted pair cable, just the individual conductor pairs, or both the entire cable and individual pairs.  In a shielded code, the letters before the slash designates the shielding on the entire cable; the code after the slash signifies shielding for the individual pairs.  For example:

 

Here is a glossary of terms to help you decode cable shielding:

 

 

FTP – Foiled Twisted Pair : An additional layer of protection is created with shielding/screening wrapped around the individual twisted wires. 

 

STP – Shielded Twisted Pair : Braided shielding wrapped around the individual twisted wires adds a layer of protection.

 

F/UTP – Foiled/Unshielded Twisted Pair : An overall foil shield encases the 4 pairs of unshielded twisted pair. Commonly used in 10GBaseT applications.


S/UTP – Shielded/Unshielded Twisted Pair :  An overall braid shield is wrapped around all 4 pairs of unshielded twisted pair.


SFTP – Shielded and Foiled Twisted Pair : Foil shielding around the individual twisted wires and an overall shield that is sometimes a flexible braided shield. This provides the highest level of protection from interference.

 

SF/UTP – Shielded and Foiled/Unshielded Twisted Pair : Both an overall braid screen and foil shield with unshielded twisted pairs. Occasionally referred to as an STP cable, these cables are very effective at protecting EMI/RFI from entering or exiting the cable.


S/FTP – Shielded Foiled/Twisted Pair : An overall braid shield with foil-shielded twisted pairs. The shield underneath the jacket is a braid and each individual pair is surrounded by its own foil shield. The purpose of the additional foil on individual pairs is to limit the amount of crosstalk between them.


F/FTP – Foiled/Foiled Twisted Pair : An overall foil shield with foil screened twisted pairs. Like F/UTP, this cable is commonly used in 10GBaseT applications.


U/FTP – Unshielded/Foiled Twisted Pair : No overall shielding or braid with foil-shielded twisted pairs. This cable is also frequently used in 10GBaseT applications.

 

U/UTP (UTP) – Unshielded/Unshielded Twisted Pair : Pairs of wires twisted together that are not shielded at all. These cables are often referred to as UTP andare one of the most basic methods used to help prevent electromagnetic interference. 

 

5 Things You Need to Know About Shielded Ethernet Cables

August 18, 2016 at 8:00 AM

 

Shielded Ethernet cables are widely used, so you may know what they are. You may even be familiar with some of the advantages and disadvantages of using them. But if you want to dig a little deeper into the world of shielded Ethernet cables, here are 5 things you need to know.

 

1. A single-shielded Ethernet cable has the lightest available shield but still weighs 12% more on average than an unshielded cable. A double-shielded Ethernet cable weighs as much as 30% more than the unshielded version. This additional weight may not be a big deal if you are only running a few shorter cables, but if your network is using dozens or hundreds of shielded cables, the combined weight could be enough to damage a rack, cable ladder or other cable management infrastructure. 

 

2. Double-shielded cables  have both a foil and braid shield and can better protect data from EMI/RFI and alien crosstalk (AXT). This protection results in higher transmission speeds and fewer data transmission errors.

 

 

3. High-flex industrial cables are shielded and built for continuous or high-flex applications, and also employ special jacket materials to solve common industrial Ethernet problems. They are designed for environments where ordinary patch cables fail. These cables will not breakdown when exposed to oil based lubricants, making them ideal for robotic control systems on the factory floor.

 

4. Shielded IP67-rated and IP68-rated Ethernet cables use a hood around the male connector that can screw onto the barrel of a female jack for protection against moisture and dust. Shielding the cables and connectors ensures better performance and higher data transmission rates.  IP67 and IP68-rated cables are also protected from liquid immersion, giving them another layer of protection.

 

5. Shielded Ethernet cables provide maximum performance even in high EMI/RFI environments.   Category 6 shielded cables are designed to handle today's hi-speed Gigabit Ethernet applications. Category 6a cable assemblies offer true 10 Gigabit Ethernet speeds at frequencies up to 500 MHz, making them ideal for high speed computing applications often found in data centers. Both Cat6 and Cat6a shielded cables are designed to outperform with super speeds and shielding protecting your data from interference.

 

Video Blog: How to Make Your Own Shielded Ethernet Cable

May 19, 2016 at 8:00 AM

 

If your application requires extra protection from electromagnetic or radio interference, shielded cable may be the perfect solution.  When installing cabling or network devices in close proximity to machines, motors, power cables, fluorescent lights or other electronics that produce high electromagnetic or radio frequency interference (EMI/RFI), shielding will protect the data from EMI/RFI, increase transmission speeds and reduce data transmission errors.  A shielded Ethernet cable also protects from alien cross talk (AXT), caused by other cables and nearby connected devices.

 

If you do require shielded Ethernet cables you can either buy pre-assembled cables or you can build your own. We have created a helpful video to assist you if you decide to go the DIY route.

 

Our instructional video demonstrates an easy life hack to make your own shielded Ethernet cable. With just 4 items and 3 short minutes, our simple steps will show you how to build your own shielded Ethernet cable. Go ahead, bring out your inner MacGyver – you know you want to.

 

For more information on shielded cables, read our blog Who Needs Shielded Cables Anyway.

 


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