Differences Between Cat6 and Cat6a Cables



Back when the first wave of Category 6a cable came out in 2008, it was 50% larger than the average Cat6. Since then, many manufacturers have managed to slim down their Cat6a cables by up to 10%. With Cat6a, there is an unprecedented emphasis on twist; while Cat6 combines tight pair twists with extra insulation to reduce crosstalk, Cat6a takes things even further by additionally twisting each pair around a flexible (and twisted) central plastic support.

Seeing as how demands for greater bandwidth and less attenuation only increase over time, the consensus among installers is that Cat6a’s size and weight issues are more than made up for by its overall speed and resistance to crosstalk.

There are just a few things to remember and plan for when you’re working with Cat6a:

It’s heavy.

With the added size of Cat6a comes a significant increase in weight, which affects how many cables you’ll be able to fit into a cable tray, as well as where you can place them. Cable tray capacity is drastically reduced when you’re using Cat6a cable, because it takes up way more space. That means bigger cable trays and conduit, as well as a restriction on bundle size. It’s recommended that you bundle no more than 50 Cat6a cables at a time. In-tray placement is also key: always make sure to place Cat6a at the bottom of the basket, so that it won’t crush smaller-diameter cables with its massive girth.

It Requires a Bigger Bend Radius.

There may be a few exceptions, but as a rule of thumb, the larger a cable’s diameter is, the larger its bend radius needs to be. The wider bend radius of Cat6a cable requires more room than the tighter bend of thinner network cables. It’s important to allow extra space anywhere your Cat6a cables may need to bend, be that behind a wall jack or at the end of a cable tray run.

It Doesn’t Like Zip Ties.

When you use standard cable ties on any type of network cable, it pays to be gentle, because there’s always the risk of attenuation due to over-tightening. However, Cat6a cable is exceptionally prone to crushing, so it’s best to use wider, looser hook-and-loop cable straps, in place of the plastic zip ties that you’d normally reach for.

It’s Packaged Differently Than Other Category Cables.
A lot of installers have grown accustomed to dispensing Cat5 and Cat6 cable from convenient pull-box packages, but Cat6a is most widely available on reels. This isn’t a deterrent to most people, but it does mean that you’ll have to plan accordingly, and keep a strong, appropriately sized stand or cart on hand for storage, transport and dispensing.

It Needs More Testing.

Since it’s capable of speeds up to 500 MHz and alien crosstalk begins at only 350 MHz, Cat6a needs more testing than earlier categories of network cabling. When quoting a job requiring Cat6a cable, be sure to budget extra time for the following tests: alien attenuation crosstalk ratio far-end (AACRF), alien far-end crosstalk (AFEXT), alien near-end crosstalk (ANEXT), power sum alien attenuation crosstalk ratio far-end (PSAACRF), power sum alien far-end crosstalk (PSAFEXT), and power sum alien near-end crosstalk (PSANEXT).