Putting PoE to New Uses

There’s a new technology available for security professionals, and it’s been on the market for almost two decades.

Power over Ethernet (PoE) technology is widely used across diverse security and surveillance applications. However, the latest version of the standard, first established in 2003, has evolved the technology’s capabilities to the point where professionals are now finding entirely new uses for PoE-enabled cameras and devices.

The PoE standard was first ratified by the IEEE in 2003, initially as 802.3af, and allowed a camera or other PoE device to receive up to 12.95 watts of power, with the second standard – 802.3at – doubling that to 25.5 watts.

PoE technology enables integrators to easily onboard, connect, configure and integrate different types of systems without having to learn a whole new “language” and without needing to home run cables to disparate systems.

That’s a significant cost-savings because now you don’t need to deploy multiple outlets everywhere. You don’t need to run 18/2 copper cabling. You don’t need to deal with additional power supplies. You have a single cable for the data and power, and it makes functions like UPS battery backup easier because now it’s all centralized.

For integrators, requiring fewer cable runs to deliver power and network to a camera makes it easier to install new products or design a system for a new facility.

There are also PoE extenders that you can plug in inline, so you don’t need a local 110-volt power source. It essentially steals a bit of power, goes inline and then it pushes out the rest of the power supply, extending the distance for delivering power. There are also ways to daisy chain and keep going further and further.

PoE technology can also do much more, if used properly. The technology can extend beyond cameras to include lighting, digital signage, clocks, access control, entry and access badging systems, encoders, decoders, Public View Monitors, anything really.

The standards have evolved, supporting higher network speeds – now up to 10 gig — and allowing for more watts to be received — now up to 71.3 watts in the highest case.

As new standards have come out, we’ve kept pace by upgrading and enhancing our cameras to best take advantage of each technology leap. Here’s a perfect example of how the new BT standard can enable project applications never before possible: PTZ cameras with low temperature environment capabilities, but also with ultra-long range, powerful IR LEDs to see far away in near total darkness.

Know Your Terminology

When it comes to PoE, there are two key terms: PD and a PSE.

A PD is your Powered Device: cameras, speaker, any device receiving power. A PSE is Power Sourcing Equipment. The PSE consumes a certain amount of power, but it can’t deliver the full amount of power needed due to loss along the cable run. For example, in standard PoE, your switch, your injector, your mid-span consumes up to 15.4 watts, but the camera can only receive 12.95 watts.

When designing a system, professionals need to make sure they look at each device’s data sheet. If it says “12.95 watts,” you can’t use that number by itself to size how big your power budget is on your infrastructure. If you have a 32-port switch, or even a 48-port switch, then 12.95 times 48 equals 621 watts. But 15.4 times 48 is 739. That’s a difference of 118 watts, which could cause devices to not receive enough power, changing your PSE selection. It’s important to always be cognizant of what the actual power draw is on the switch side.

Also, just because a switch says it can do PoE+, it probably can’t do that on all the ports. Keep in mind your total system budget, and also how much power each camera or each device needs. Then add it all up to make sure that switch can fully support your network requirements.

Remember: the “E” in PoE doesn’t mean “everything.” There is no one size fits all.

For more information, check out Hanwha Techwin’s range of PoE+ switches, injectors and NVRs at hanwhavisionamerica.com.