PoE May Equal "Big Mo" for Contractors

By Joe Salimando | Nov 15, 2004
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How about this: Under IEEE Standard 803.2af, power can be run via datacomm cable. It's called “Power over Ethernet” (PoE). For many electrical contractors, PoE could turn out to be the greatest development in world history.

But wait: Maybe it's not all that remarkable. After all, power has been run to tens of millions of homes over plain old telephone lines for decades. It takes what, a couple of volts, to get a telephone to ring. So, what's the big deal?

Viewed in that light, one might say that all PoE amounts to is an upgrade of very old technology. Everyone knows electrical power can travel over copper wires; the 803.2af standard is about doing just that (albeit, with data flying over the same lines at the same time). To take the ultimate skeptic's approach, perhaps the transmission of 48V over datacomm cables is no one's idea of a revolutionary development.

In fact, the 803.2af standard's June 2003 debut came without raves or excitement for those in the IT business. Compared to the ongoing brouhaha over the not-yet-ready-for-prime-time 10-gigabit-Ethernet standard, the official coming of PoE went virtually unnoticed. What's become clear recently are the following basic items:

o PoE may catch on slowly because the folks responsible for data networks-the IT managers, MIS personnel and CIOs-are information technology people, not “power people.” PoE puts them into the power realm, not their comfort zone.

o While distribution of 48V-a maximum 13W of power-over a datacomm cable does not threaten standard 110/220 power distribution, there will be some “loss” of standard electrical work. An example is wireless access points (WAPs).

o Can nonelectricians complete PoE installations? Yes. We're talking about doing little more than installing data cable here. Should they be asked to do so? Maybe not.

o Unlike other datacomm technologies, this one will apparently undergo a slow roll-out. One reason is the lack of compatibility with most previously installed network equipment.

o Perhaps lengthy, nonflashy development of PoE technology applications won't be all bad for everyone involved-corporate customers, their IT decision-makers, their end-user employees-and contractors who perform both electrical and datacomm work.

Quiet Debut

While combining data and power over a single copper cable might have tremendous implications for building systems technology, the market roll-out has been accompanied by the sounds of silence. A Google search of the term “Power over Ethernet” in quotes drew only 169,000 responses around Labor Day 2004.

For comparison purposes, “Britney Spears” drew 4.4 million hits. Surprisingly, the phrase (in quotes) “10 gigabit Ethernet” drew 113,000, and it's not yet a standard. Searches on sites of networking and IT industry magazines drew a modest response, including the following:

o Network Computing's Web site produced 39 hits for “Power over Ethernet.” “Ethernet” turned up 1,125 hits.

o At the Network World Fusion site, there were 79 PoE links and 193 for 10-gig. “Cisco Systems” drew 216 links.

o With 401,000 readers, eWeek magazine reaches more IT professionals than either of the above. A search here produced 44 links for PoE, 78 for 10-gig and 139 for WLAN (wireless LAN).

Why is PoE a stepchild, at least so far? One reason might be the limited amount of power allowed by the 803.2af standard. There are only 13W to work with-enough to power WAPs, VoIP telephones, pan-and-tilt security cameras and a bit more. PoE does not even supply enough power to run a laptop computer. By that criterion, PoE isn't there yet.

Powering WAPs

In industry meetings, electrical contractors who also do datacomm work have claimed that the coming of wireless has not been a bad thing. In-building wireless LANs need many WAPs and, for each individual point, the WLAN needs datacomm cable, running to the WAP; setting and testing of the WAP itself; and an additional outlet to power the WAP.

There are dollar signs attached to each of those criteria, the contractors have noted.

But as PoE is adapted, the extra-added remote power outlet is disappearing from work orders.

Who Will Install It?

Obviously, it's time to pound the panic button. Will electrical contractors helplessly watch tens of millions of dollars in annual electrical work vaporize?

To sum up: Perhaps it is “PoE = Woe unto electrical contractors.” Follow here with an appropriate amount of grief, lamentation and genuine sorrow that all readers of this magazine didn't choose something practical, such as plumbing or bricklaying, for a career.

Maybe lamentation and regret aren't your thing, and perhaps they should not be. In a selection of articles, Cameron Sturdevant, a columnist for eWeek magazine, said that there is excitement-anticipation, even-about PoE beneath the outward calm of IT professionals.

It's just possible that instead of woe from PoE, electrical contractors will find that, as this technology's popularity grows over time, customer needs will work to the contractor's advantage.

Working It In

It is possible that PoE is already making inroads. Some concrete examples are the following:

o Security-CCTV cameras installed years ago need three wires/cables to perform pan-and-tilt movement: One to carry the image, one to power the camera and another to send data signals (to tell the camera which way to move.). With PoE, that's all on one wire. To take advantage of this, distributor Anixter rolled out an assembly of products for its CCTP security offering in January 2003.

o VoIP-Phones for voice over Internet need to ring. VoIP is said to be “the most common reason companies gravitate” to PoE, according to analyst Chris Kozup of Meta Group (as quoted in the New York Times).

o Intercom-Some school districts want an intercom system in every classroom. A school system in La Mesa, Calif., put a PoE-based intercom system in each classroom for a reported $20,000 vs. a $170,000 estimate for a traditional installation.

That's the tip of the iceberg. As Sturdevant noted in two articles on the subject, the “problem” for PoE in its fledgling stage is the human imagination. What's more, IT executives and staff who will be in charge of PoE decision-making and implementation are not, as previously noted, power people.

Taking full advantage of PoE, then, will depend on vendor product roll-outs and field applications suggested and marketed by vendors, demonstrated and adjusted in place by customers, and created by contractors.

A Potential Boon

While adoption of PoE has been slow thus far, there is good reason to believe that the situation might evolve into the opposite of “PoE = Woe” for electrical contractors.

Why? “Introduction of power into a networking environment has the potential to create a skills crisis. Most networking professionals aren't certified or trained in power operations,” said Chris Kozup, a Meta Group program director, in a Network magazine PoE Q-and-A.

“This has more to do with the fact that the majority of networking professionals don't have any experience with power,” Kozup continued.

There's a major disconnect here; it's held PoE back thus far and may lead to slow progress in the near term. But from the perspective of ELECTRICAL CONTRACTOR readers, it might not be a bad thing. Consider the following:

o Electrical engineers haven't “schooled” themselves, for the most part, on datacomm issues.

o Telecomm/datacomm systems designers don't have electrical engineering degrees and know little or nothing about power. Anecdotal evidence suggests they aren't so hot with grounding and bonding of telecomm and datacomm systems already extant (e.g., those in the field now that don't include PoE).

o Those given IT responsibility on the customer end know little about power. PoE will apparently become the property of the IT department, not of the building or facility manager.

o Most security installation companies do not have an electrical license and are not familiar with electrical codes and power system needs.

Despite these points, the applications and advantages of PoE, already attractive now, are likely to become only more alluring in the near future.

Where can one find “experts” in integrating power technologies with datacomm in the wider world? Apparently, there's only one place to do that-at an electrical contracting company. EC

SALIMANDO is a Vienna, Va.-based freelance writer and frequent contributor to ELECTRICAL CONTRACTOR. He can be reached at [email protected].


About The Author

Joe Salimando is a Vienna, Va.-based freelance writer and frequent contributor to ELECTRICAL CONTRACTOR. He can be reached at [email protected].





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