Teaching an Old Dog New Tricks

Since the Power over Ethernet (PoE) standard was finalized in late 2003, there has not been a better time for facility owners to embrace it. And there is, perhaps, no group better suited to introduce and implement it than electrical contractors (ECs).

PoE technology allows electrical currents to travel over Ethernet cables to operate low-powered network-connected devices, such as voice over Internet protocol (VoIP) phones, wireless access points and network-connected surveillance cameras. This power source reduces deployment costs by eliminating the need for electrical power outlets near the devices.

The actual power for PoE devices is delivered from one of two types of power sourcing equipment, both of which are typically rack-mounted in a network telecommunications room. Endspan power comes from a PoE-enabled switch, and midspan power comes from a secondary hub that injects power into the channel. Midspan power is useful when retrofitting an existing network to PoE because it allows a network owner to continue using existing telecommunications switches and avoid costly upgrades and reconfiguration to switch settings.

Scott Lennartz, Cisco’s manager of product marketing for the Ethernet Switching Technology Group, said PoE has been driven by Internet protocol (IP) telephony.

PoE is green

The potential for energy savings is a notable PoE feature in these times of high-cost energy and green construction because it enables convenient power management options over a standards-based IP network.

“Devices that are powered by AC outlets are on all the time,” said Mike Pula, Panduit’s technical marketing manager. “But anything that is powered by PoE can be easily and automatically powered down when not in use. Most businesses don’t need to power their IP phones, keep their wireless networks operational, or keep all of their internal security cameras up and running after hours.”

Electrical contractors are poised to deliver that energy-saving message. Although PoE has always had this capability, the growing emphasis on energy efficiency has stimulated interest in this aspect.

If a commercial or industrial facility were to aggressively convert from AC- to PoE-powered devices, it could realistically see a drop in its total cost of ownership. But building maintenance and IT staff members may not be aware of that, so this is a money-saving opportunity electrical contractors can raise with their customers.

PoE Plus

But there are more than just the existing benefits of PoE that many businesses may be missing. The next generation will offer even greater functionality. PoE Plus, or PoE+, expected to be released sometime in 2009, will be based on the IEEE 802.3at standard.

The current PoE standards (defined by IEEE 802.3af) allow for three levels of power per port: 4, 7 or 15.4 watts (W). PoE Plus will increase maximum power per port to at least 30W. That will allow for improvements to the types of devices already serviced by PoE, enabling things such as dual radio wireless access points. In addition, IP with additional functionality, such as video conferencing, will be available, Lennartz said. The new technology may also change IP cameras.

“PoE Plus will be able to drive a wider array of IP cameras that have pan/tilt/zoom capabilities, as well as external cameras with heaters and blowers,” said John Variakojis, a Panduit product line manager. Door-access readers, digital signage and synchronized wall clocks likely will be available with PoE Plus.

Lennartz said the increased power over the cables may require infrastructure changes.

“There will need to be enough electrical power and cooling in telecommunications rooms to support the new demands of PoE Plus,” he said. “And it will require a minimum of Cat 5e cable, where Cat 3 has worked up to now.”

Electrical contractors earn their living by ensuring their customers have access to electrical and telecommunications current when they need it. ECs don’t make money when their customers use that current. In fact, ECs can make money by helping their clients discover ways not to use electrical current, reducing their total cost of ownership by having more efficient operations.

Therefore, PoE and PoE Plus are systems ECs should be ready to discuss as preferred solutions for the right circumstances with facility owners and IT managers. Since some manufacturers are marketing PoE as a way of saving the cost of using an EC to install AC outlets to power these devices, it is especially important for ECs to act first by marketing their PoE installation services.

MUNYAN is a freelance writer in Olathe, Kan., specializing in technical and business writing. He can be reached at www.russwrites.com.

About the Author

Russ Munyan

Freelance Writer
Russ Munyan is a freelance writer in Olathe, Kan., specializing in technical and business writing. He can be reached at www.russwrites.com

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