PoE

Power Over Ethernet, commonly known as PoE, is a way of delivering low levels of power to devices, including wifi hotspots, security cameras, and IP phones, without the use of a power cable. Ethernet cables, including CAT5, CAT5e, and the new CAT6 cables, can all deliver power. This is particularly useful for devices installed high up, inside walls, outside, or anywhere else traditional power hook-ups aren’t easily available. A company looking to install an outdoor security camera should strongly consider PoE. By purchasing a network-based camera, which is controlled and transmits data over the network, all you would require is a single cable leading to the outside for full operation of the camera. However, with all this power running over the ethernet cable, especially when exposed to the elements, including a proper ethernet surge protector becomes essential. This article will discuss why protection is useful, and will discuss the installation of a network surge protector. For additional information, consult the manual that comes with the device.

Consider what happens during a thunder storm if a utility pole is hit. The utility pole, like your security camera, has a lot of highly conductive metal on it and so, like your security camera, is highly likely to be hit. For this reason, many utility poles have what is called a lightning arrester, a small device with a grounding wire leading all the way to the ground below that detects unnatural surges in power to the pole, and redirects it along the ground wire to be safely dissipated. Otherwise, the power would travel along the wires, causing dramatic power surges in people’s homes, leading to fried electronics and thousands of dollars in lost equipment.

With an outdoor camera, the risk is even greater. Power surges can occur, not simply through lightning strikes, but through the natural degradation of cables. Standard ethernet cables aren’t designed for outdoor operation. There are specialized outdoor cables, but even these have piping that will begin to degrade over time, with extreme temperatures and high humidity. Should the wiring inside the cable get exposed or get wet, that in itself can result in a short, causing a power surge large enough to fry motherboards and render other network components useless. If it’s an option, burying the cable will do some good to help extend its life, but if your security camera is mounted up high, at least some of the cable will certainly be exposed.

For this reason, installing a proper ethernet surge protector is particularly important. Like the utility pole’s lightning arrester, a PoE surge protector is grounded and has the ability to detect surges in power, and redirect that power to be dissipated through the ground. The device should be installed directly before the camera’s ethernet cable arrives at the network switch. Installation is relatively simple. The device is a box with an ‘in’ side, where you install the cable coming from your cable, and an ‘out’ side, which is installed to the switch. The only other setup is grounding the device. Common options for grounding include a DIN rail (a system you may already be using for your network casing) or ground wire connected to a UPS ground screw or ground lug.

This system isn’t perfect. In case of lightning strike, the camera may still be fried, but the surge won’t extend beyond, affecting your switch or the other computers on the network – say the computer that was being used to monitor the camera, which may have surveillance records or thousands of dollars of other computer equipment. By installing an ethernet surge protector, you help insulate your network from the elements and unpredictability of the outside world.