Smart Building

What’s the Real Cat 6A Cable Distance Limit (and Why Does It Matter)?

Ron Tellas

When you invest in Cat 6A cable, you’re making a decision to support your organization and its technology infrastructure for the long term. With this type of cabling system in place, you’ll be ready to support next-generation wireless, 4-pair Power over Ethernet (PoE), HDBaseT and digital buildings – and other technologies just entering the picture.

Because of these bandwidth-intensive applications, many standards are already recommending Cat 6A cabling for new installations. And, because Cat 6A cables can support a full 100 m distance across the entire channel, you assume that all Cat 6A cables that will do just that. Right? Not so fast! There is a Cat 6A cable distance limit based on how cables are designed and deployed.


The longer the path that data has to travel, the more susceptible it is to signal degradation. There are certain factors that can negatively impact data transmission along a cable, impacting the Cat 6A cable distance limit.


Cat 6A Cable Distance Limit: Outside Diameter (OD)

Small-diameter Category 6A cables may not be able to support the full 100 m distance. In the past, Cat 6A cables were always typically larger in diameter because they operate at frequencies of up to 500 MHz (which is twice as high as Cat 6) and require thicker/more materials, such as outer jackets or larger splines, to adequately control noise and crosstalk at these levels.


Many of today’s Cat 6A cables still remain significantly larger and heavier than other options, but newer Cat 6A cables with smaller diameters are available. Although they make installation faster and easier, these small-diameter cables may impact Cat 6A cable distance limits if they’re not designed correctly.


Cat 6A Cable Distance Limit: Heat/Power

Cable temperature rise impacts the electrical characteristics of a cable. For example, a cable’s insertion loss (the ratio of received to inserted signal power at the end of a cable) increases as cable temperature rises. Cable attenuation (reduction of signal strength) is significantly impacted by temperature, too.


There are a few things that can cause heat build-up inside a cable:

  • Tightly packed cable trays that don’t allow adequate air circulation or opportunity for heat dissipation
  • The use of PoE technology (especially when current levels are high inside the cable – as current levels increase, so do heat levels)
  • Use in higher-temperature environments, such as above equipment

When these situations occur, they can negatively impact Cat 6A cable distance limits.


The Cable that Goes the Distance

When these factors impact distance, a cable often has to be length de-rated in order to maintain performance levels. The bottom line is this: Only when a cable is designed and manufactured to fulfill the full 100 m reach will it be able to do so.


When investing in a cable Cat 6A cable that can perform across the entire channel, there are a few things to look for:

  • Thermal-barrier designs that distribute heat around the circumference of the cable, eliminating hotspots and keeping thermal rise within acceptable limits
  • Cables with UL’s Limited Power (LP) certification, which ensures that cables don’t exceed jacketing temperature ratings under certain conditions
  • The ability to maintain promised performance levels under higher temperatures
  • A small diameter that offers weight and diameter reductions while still being able to handle heat

A Cat 6A cable that can successfully transmit data across the full 100 m channel not only provides an extra margin of performance, but also supports a wider range of data center and network configurations.


Belden 10GXS Cable is the only Cat 6A cable proven to reach distances of up to 100 m while maintaining promised performance levels – even despite higher heat levels. It also features a smaller diameter and utilizes EquiBlock™ Barrier Technology to achieve uniform heat-flow dissipation.


If you want to learn more about designing a cabling system that reaches distances of up to 100 m without a degradation in performance, contact us or learn more here