I need PoE for some devices (CCTV cameras, WiFI Access Points) - can these wires be run in parallel with
- Cat6 cables going to non PoE devices (e.g. datapoints of PC)
- Cat6 HDBaseT Cables being used for HDMI over Cat6
Super User is a question and answer site for computer enthusiasts and power users. It only takes a minute to sign up.Sign up to join this community
Yes. But you should be running Cat6A cable because of heat dissipation not interference (see later).
Cat6 can be shielded or unshielded. Shielded will clearly be better.
Cat7 has an overall shield as well as individual shielding of every pair (so may be even more suitable).
Twisted pair cables are HIGHLY resistant to interference pickup. Furthermore, DC does not cause interference, since it is basically an unchanging current, so there's no change in magnetic fields from it to cause interference (other than when turned on, and off - and the twisted pair cables will reject that interference by design, anyway.)
I have many bundles of cables including POE cables in my work role. Interference is not a factor.
In fact, a new PoE standard, IEEE 802.3bt, supports up to 100W of power per cable.
But higher power levels running through a cable can cause performance issues – namely by making the cable hotter. And when the cable gets hotter, insertion loss increases. This escalates your chances of your business experiencing a productivity killer – downtime – and may also damage the cable itself.
You’re better off using Category 6A for a number of reasons we’re going to cover here.
A cable that offers a larger conductor diameter can reduce resistance and keep power waste to a minimum because it has a lower temperature increase compared to smaller-gauge Category 5e and Category 6 cables. This better performance will provide additional flexibility, including larger bundle sizes, closed installation conditions and higher ambient temperatures.
For example, when comparing 23-gauge and 24-gauge cabling, there is a large variance in how power is handled. As much as 20% of the power through the cable can get “lost” in a 24-gauge Category 5e cable, leading to inefficiency.
Less Power Loss
Energy efficiency increases when structured cable maximizes the power running through it to waste as little as possible.
As we mentioned above, losing nearly one-fifth of the total power in a 24-gauge Category 5e cable may seem like a lot of power loss – and it is. But doing the math will show you that the total dollar amount comes out to be only around $7 per year. The numbers start adding up; however, when you realize that it costs $7 per year per PoE device across your entire facility or campus – from surveillance cameras to wireless access points. Although it may seem like a small dollar amount when viewed out of context, power dissipation through a cable can ultimately lead to higher-than-necessary operating costs.
It’s also important to keep in mind that the number of Power over Ethernet devices is only going to increase in your facility as you install more wireless access points to support things like BYOD (bring your own device). As a result, you’ll need more PoE cable – and there will be more opportunity for wasted energy.
Less power is dissipated in a 23-gauge Category 6A cable, which means that more of the power being transferred through the cable is actually being used, improving energy efficiency and lowering operating costs.
Tightly Packed Cables
If your cables are tightly packed in their trays and pathways, the chance for heat increases because it doesn’t have a chance to dissipate away from the cable.
Some Category 6A cable has enough insertion loss margin to handle the extra heat generated from tightly packed cables without impacting performance. (This doesn’t apply to all Category 6A cables. Even though they promise a 100 m solution, some cables may become an 85 m solution if the temperature increase is too high.)
Belden 10GXS cable can handle the added heat while maintaining its full 100 m performance – and it’s the only Category 6A cable that can make this claim.