Power over
Ethernet (PoE) IP Network Cameras
Power over Ethernet IP network cameras eliminates the need for a mains power outlet at each of the camera locations that you would need with a traditional analogue CCTV system. This makes installation easier and cheaper since there is no need for separate power and data cable infrastructure and the cost for an electrician to install mains AC outlets.
Axxess 28 can advise on the technical aspects of CCTV surveillance, whilst you make the most of your structured cabling and network for the management and image recording of the IP network cameras.
Uninterrupted Power Supply (UPS)
Another benefit of Power over Ethernet is the UPS function. Many companies have their network switches connected to a UPS (Uninterrupted Power Supply) device. Since the Power over Ethernet hubs are connected to the network switches, the cameras and video servers can continue to function even in the case of a power shortage.
IEEE 802.3af
PoE technology is regulated in a standard called IEEE 802.3af and is designed in a way that does not degrade the network data communication performance or decrease the network reach. The power delivered over the LAN infrastructure is automatically activated when a compatible terminal is identified, and blocked to legacy devices that are not compatible. This feature allows users to freely and safely mix legacy and PoE-compatible devices, on their network.
The standard provides power up to 15.4W on the switch or mid-span side, which translates to a maximum power consumption of 12.9W on the device/camera side making it suitable for indoor cameras. Outdoor cameras as well as PTZ and dome cameras normally have a power consumption that exceeds this, making PoE functionality less suitable. Some manufacturers also offer non-standard proprietary products providing suitable power for these applications as well, but it should be noted that since these are non-standard products, no interoperability between different brands is possible. The 802.3af standard also provides support for so-called power classification, which allows for a negotiation of power consumption between the PoE unit and the devices. This means an intelligent switch can reserve sufficient, and not superfluous, power for the device (camera) - with the possible result that the switch could enable more PoE outputs.
Power-over-Ethernet support in Mobotix, Axis and IQEye products
Axis, IQEye and Mobotix provides network video products with or without built-in support for Power over Ethernet. A PoE Active Splitter, which splits Ethernet and power coming over the network, can be used to provide PoE support for Axis network video products without built-in PoE. Several Power over Ethernet accessories are available.
T: 0845 680 0228 | F: 0845 680 0229 | E: sales@axxess28.com
Copyright © 2001-2010 Axxess 28 Limited. All rights reserved.