The PoE Advantage in Video Surveillance Cameras

24/09/2015 0 Comment(s) Surveillance Equipment,

Power over Ethernet (PoE) is a technology that supplies power to video surveillance cameras through an Ethernet cord. It allows network cables to carry electrical power to the surveillance cameras and at the same time gives each camera direct network access. It simplifies the installation of digital security cameras because you will not need a power supply socket for each camera since the network cables carry electrical power.

PoE is a technology that was initially developed in 2000 by Cisco for VoIP phone systems to reduce noise, and has since then emerged as a simple solution when installing networked video surveillance systems. The wider application of PoE to IP cameras and wireless systems has resulted to the implementation of standards that foster uniformity among PoE device manufacturers. With PoE, installation of multiple surveillance cameras for your security network requires only one cable for the PoE switch and all of the security cameras, using a single power supply.


How PoE Works

You have greater flexibility in the placement of video surveillance cameras and the installation process is easier with PoE because it requires only a single network cable such as Cat-5e, Cat-5, or Cat-6 for both network and power connections. A special power switch is built into IP cameras that are wired for PoE, which enables them to use power that flows through the Ethernet cord. Since power flows through the cable and into each PoE wired IP camera, the placement of each becomes independent from the availability of power supply sockets.

The PoE video surveillance system has each of the cameras broadcasting a digital video stream over your local are network (LAN) through the same Ethernet cable that supplies the power. The digital feeds give high-resolution video images through signals that a Network Video Recorder (NVR) captures, compresses, and records.

The NVR combines the video streams from each of the IP cameras, and then handles the broadcast over the local network for close surveillance, or sends the images through the Internet for remote viewing. The set-up with PoE provides greater flexibility since you can position the surveillance cameras even in locations that are quite far from power supply sockets, for example on top of roofs and along walls that allows the positioning of a single Ethernet cable.

Older IP cameras that do not have PoE built-in that you still want to use can be incorporated in the PoE using a PoE splitter that will convert the power and data supply of the camera. Power over Ethernet provides reliable power supply since the power comes from a central source rather that several wall sockets or adapters. You can even have the system backed-up by an uninterruptible power source that can be controlled when you have to reset or disable some of the devices.

For video surveillance systems that require the connection of a large number of cameras that the limited number of ports in a router cannot accommodate, a PoE switch can be used to connect the large number of security devices. The PoE switch has a built-in PoE injection system that facilitates the connection of other network devices in the same manner as normal switches are used. It can detect if the connected device is PoE-compatible and automatically supplies power to it. Any device that is not PoE compatible can send images to the NVR, but you have to connect it to an electrical socket to power it up.

There are switches that cannot handle a PoE and if this is the case with some of your security devices, you have the alternative to use a PoE Midspan that can inject power into the installed network cables. The midspan, also called a PoE injector, can make regular non-PoE network links PoE capable. You do not have to replace existing LAN installations when upgrading to PoE. Rather, you can install midspans to upgrade the existing LAN while at the same time providing a versatile installation set-up that will require fewer PoE ports. The upgrade is done by patching each network connection through the midspan, resulting to automatic power injection.


How You Benefit from PoE

It is important for video surveillance systems to maintain network connection particularly when you collect and save video files to a Network Video Recorder (NVR), and even to the newer system of cloud storage. When you use PoE-enabled IP cameras, these units remain connected to the network and efficiently send a regular stream of video files to the NVR. The system will not suffer from any intermittent loss of connectivity that is possible for wireless systems, and the speed of video streams remains consistent.

Some of the applications of PoE cameras that are available in various types that include HD, dome, and fixed are the following:

  • Staying connected to your home when you have to work long hours in your office, or monitoring activities in your office while you are at home
  • Discreet monitoring of commercial establishments such as retail stores and shops to gather information about shopping preferences, shoppers’ reaction to promotional deals, and surveillance to prevent theft
  • Monitoring progress in construction sites
  • Monitoring activities in industrial sites such as warehouses, factories, and shipping facilities



The many benefits that PoE brings has certain advantages that include cost and time savings that can be realized from doing away with the installation of electrical power cables, and the flexibility of camera deployment brought by the independence from electrical outlets. You can even re-position or redeploy your devices with minimal disturbance on your network services because you only have to deal with a single Ethernet cable. Other benefits that you can derive from the PoE installation are safety features that protect network equipment from under-powering or overload, and the reliability of power supply that comes from an uninterruptible power source.



The deployment of PoE video surveillance cameras for your security network has the advantages of cost savings and flexibility, and when you have an existing network that you want to upgrade, you have the option of using existing devices with a PoE Switch and a PoE Midspan. 

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