Project Profile: Going the Distance with PoE

IP technology promises much to the security industry but it can often cloud the reality of deploying IP-based systems beyond Ethernet’s 100-meter distance limitations.

The wonders of IP technology are even more elusive to those who have no means of powering a device that is far away or nowhere near a power source. Such was the case when a regional utility company reached out to Dan Tullis, system architect, TNT Technologies, Las Vegas to assist in securing company offices, warehouses, buildings and transmission stations owned by a utility company in the Mojave Desert region. The technology of choice? IP CCTV video surveillance, access control and perimeter security.

“A big issue for IP technologies is that a lot of end devices are installed beyond 100 meters feet from the head-end device,” explained Tullis. “The facilities were not equipped or designed to accept IP equipment—the original architectural design of the facility never planned for the 100 meter limitation of Category 5a or 6a copper data cabling. To meet the demands of the project, we would need to go well over 2,000 feet with some of the cable runs. At many locations, there were no access points or junction boxes along the conduit’s route. Even if we could find a way to get data to and from the IP end devices, how would we power them?”

Getting to the solution
The technologies Tullis first considered came up short in terms of distance and cost. Ethernet repeaters (i.e. Ethernet bridges) were not an option because these devices only repeat Ethernet’s signals, they do not extend the distance between devices. This would have required Tullis to purchase numerous Ethernet repeaters per run, a very costly proposition over long distances. What’s more, each Ethernet repeater would require its own power source, which would have complicated the basic design many times over. Fiber was another possibility, but laying down fiber would require a whole different skill set, more dollars and it still wouldn’t solve the problem of getting power to IP cameras that weren’t near a power source.

The solution? Ethernet extenders that not only overcame this distance limitation of copper-based Ethernet but that also extend PoE’s power to most IP end devices, an all-round cost-effective solution.

“Ethernet extenders seemed a little too good to be true,” Tullis continued. But Ethernet Extension Experts’ Ethernet extender kits, designed to take an Ethernet data signal and extend it up to over a mile away (without PoE; 2,500 feet with PoE) over basic category-rated cabling, or even telcommunications copper pair (without PoE), did the trick.

After setting up the Ethernet extender kit and PoE injector, Tullis quickly realized he had extended his data signal and power (24V) all the way out to a PoE IP camera over 2,000 feet away, with no bridging devices in between and on the same cable he had originally intended on using (basic Category 5e). In many cases, the PoE switch used could provide the necessary power to the extender devices without the need of the power injector, simplifying the overall solution.

PoE opportunities
It’s evident that PoE has a presence in the security industry. We’re seeing more cameras becoming PoE capable and as IP technology continues to grow in integrated form, medium-to-enterprise projects and other large-scale applications will continue to drive the need for such technologies that address the challenges of distance and power limitation.

“There are manufacturers making cameras and other devices that comply with the PoE Plus standard but there are very few making a PoE Ethernet switch to that standard,” explained Tullis. “That would help in applications such as this. Most of the camera companies are moving to the new IP standard (IEEE802.at), especially for their high-powered outdoor cameras. The use of PoE technology in access control systems is very limited. Development of such technologies would help reduce costs and wiring complexity. The challenge I see is not all of the various components you need to make a complete system are available yet.”

Although the PoE Plus standard doubles the power that PoE devices can deliver, from 15.4 watts to 30 watts or higher, opening the possibilities in deploying PoE on access control devices, some still see PoE in the security industry as a fairly new concept.

“The security industry is just starting to move into this Ethernet PoE world and they are the ones that are going to benefit the most from the new PoE Plus standard,” said Tullis. “But it’s going to take a while for the industry to get ready for these new possibilities.”

HOW IT WORKS
Installing a PoE-enabled Ethernet extender kit is simple. Using the kit Tullis deployed, the Enable-IT 865 (PoE injector included), for example, the installer only has to connect their Ethernet cable to the PoE injector’s “IN” jack (RJ-45), then connect a short patch cable from the injector’s “OUT” jack to the base Ethernet extender’s LAN 1 port. This base extender (the CO unit), which does require 9VDC (wall adapter included), or can be powered from a properly sized PoE switch, sends the data and power over the same category-rated cabling from its “Interlink” port to the “Interlink” port of a remote self-powered “CPE” unit up to 2,500 feet away (up to 3,500 feet when only sending data). From there, you simply connect a PoE device, like a PoE IP camera to the remote/CPE unit’s LAN 1 port and you’re in business.

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