Structured Cabling Types
Cat 6 FTP Cable
What structured cabling types are available (Cat5e, Cat6, Cat6A, Cat7, Gigabit cat5e, Cat7A etc.)?
The three standards that this document looks at are Category 5e, Category 6 and Category 6A. Gigabit is an application not a cabling standard. For a given application there is a minimum category that they will work on.
The difference between in bandwidth between each copper cable types?
Cat 5e
Cat 5e is typically an unshielded relatively low cost solution that will allow speeds of up to One Gigabit per second. And the performance testing is based characterisation at frequencies up to 100Mhz. as the following table will demonstrate.
Cat 6
Cat 6 can be Unshielded or shielded, however the latter is quite uncommon, particularly in the UK market. Again it will support transmission speeds of up to One Gigabit per second. However the performance testing is carried at frequencies up to 250Mhz.
This came about as there has traditionally been a change in lead between the infrastructure cabling manufacturers and application designers.
As it turns out the main benefit of Cat 6 over Cat 5e is the ability to support some specific AV applications and protocols requiring a higher bandwidth than that offered by the 100MHz available in Cat 5e.
Cat 6A is currently the pinnacle in Copper based solutions. Almost all of which is shielded, very rare has anyone trusted an unshielded solution at these speeds. It will support 10Gigabit per second. This has been achieved by two factors the copper conductors are slightly larger and the individual shielding of the conductors allows for higher frequencies to be transmitted without the noise affecting the signal on the other conductors. The frequency covered is now up to 500Mhz.
The other aspect of a Cat 6A shielded solution is the fact that it will operate with the new PoE2 standard which will call for the ability to handle 48V DC, at up to 30watts, this is being looked at by a wide range of equipment vendors, for the control and power of IP CCTV cameras, to the next generation of Wireless Access Points.
The final element is the fact that a Cat 6A, shielded solution does not require the same level of care and thought about how the cables are dressed in the horizontal, and the level of separation from other circuits. i.e. it can be physically closer to power and it can also dressed in a much more uniform and tidy fashion, in Unshielded solutions it is actively recommended not to dress cables too tidily, as there is always the fear of alien signals being transmitted between cables when then run alongside each other for extended periods.
Average test time per cable type?
With a standard Fluke DTX 1800 you can effectively test each link in approx. 2-4 minutes, for both Cat5e and Cat6 and it is only very slightly longer for CAT6A when a couple of further measurements are carried out. It is only marginally dependent on the length of the link.
The major factor with all testing is the set up and the fact that it takes two people.
Brief summary of installation measures / standard (ie bend ratio’s, loose lay of cables etc.)?
The best advice that can be given hear is to have a look at the standard BS/EN50174 which covers all the aspects relating to installation practices. It was driven mainly with the inception of Cat6A however it is equally important for both 5e and 6. As it covers the separation of power and data within containment, the use of containment and cable identification etc.
Issues concerning laying cables loose on Cable matting in floor voids, the dressing of cable into tidy bundles are typically part of good working practice and some consultants and manufacturers will stipulate the use of Velcro tie wraps rather than plastic ones in the horizontal.
Others will specify bundles of no more than 24 cables etc. a lot of these are subjective and tender specification driven.
However the main factors relate to the bend radii of the cables both during and after installation the simple rule of thumb to apply, 8 times Outside Diameter during installation and 4 times Outside Diameter, in it’s final position.
Cost differences as an overall percentage between cable types?
It is hard to compare costs in a very basic way, the outlets themselves may have a very similar cost however the time taken to terminate a Cat5e outlet and a Cat 6A with a shielded cable is very different. In layman’s terms; it can be almost twice or even three times as long for the latter, if the installation engineer is not familiar with the product.
However the more familiar the technician becomes with the product the faster the termination time becomes.
An increasingly popular approach for cabling large areas, is now handled by way of pre-termination, where a minimum of one end is terminated in a factory style environment which greatly improves the termination times achieved.
Ethernet Applications Supported
Advantages, Disadvantages / Benefits of each cable type?
It is a very difficult question to answer and should be balanced by a preceding question, that being what are the requirements of the overall system.
Bandwidth requirements, Electrical requirements PoE, How long it will have to remain in situe etc.
Cat5e:-
- Pros – Cost, flexibility & ease of installation
- Cons – Lower performance & PoE1
- Cable Diameter – 5.2mm +/- 4%
Cat6:-
- Pros – Cost, flexibility, ease of installation & middle performance
- Cons – Cost & PoE1
- Cable Diameter – 6.3mm +/- 4%
Cat6A:-
- Pros – High end performance, PoE2 & future-proof
- Cons – Cost, flexibility, ease of installation & size of containment required
- Cable Diameter – 8mm +/- 4%
Summary
I hope the above information helps with the decision making process, however as you can see it is not a straightforward process to come up with a definitive answer.
It comes down to the business requirements, balanced against cost.