Power over Ethernet

Power over Ethernet technology is becoming increasingly popular with businesses as an easy means to update their IT, communications and office infrastructure.

It allows the easy addition of devices to make the day to day running of a business much simpler. Amongst other things it can be used for:

• IP telephones allowing extra staff to be recruited and work stations to be installed without a complicated rewiring of an existing telephone system.
• Extra WiFi access points to install work stations in new sites within a building.
• Thermometer installations to ensure fridges and freezers run at a constant temperature in retail stores, alerting the manager when a deviation occurs.

Other devices includes cash tills, emergency call buttons, PA systems, clocks, access control equipment but our main interest here is of course the use of PoE for IP CCTV cameras so just what are the advantages of this technology over analogue, HD-SDI and even standard IP….

PROs & CONs of PoE cameras

PROs

1. PoE cameras save you installation time – they only require a single network cable to operate.
2. PoE cameras save you money on cabling – network cable is comparatively cheap compared to RG59 copper cable.
3. PoE cameras are easy to power as they are not sensitive to overvoltage.
4. PoE cameras autodetect if the network supports PoE with no extra configuration.
5. PoE cameras can use the existing IT network so are an easy addition to a building’s infrastructure.
6. PoE cameras are the latest technology so they are available in high definition quality.
7. A central power source allows quick detection of a power failure and makes a UPS back up device easier to install.

CONs

1. As a new technology, there are limited styles of CCTV camera available.
2. As you would expect new technology also means they are more expensive than analogue CCTV cameras.
3. As they run on a network they require some networking knowledge for set up.
4. They can suffer from network interruptions or delays.
5. There is no worldwide IP standard as yet though ONVIF standards are becoming more prevalent.
6. PoE networks can supply up to 350mA at the camera end so may struggle with some thirstier IR and PTZ cameras.
7. Some older networks are not equipped to support PoE cameras.