Why opt for PoE video surveillance systems
Source: William Pao, a&s International
Needless to say, video surveillance
is moving more and more towards IP
. This has led to increased deployment of power-over-Ethernet (PoE)
video surveillance systems, which have various benefits.
Power-over-Ethernet (PoE) is a technology that’s growing in popularity in recent years. According to a recent report by Global Market Insights, the global PoE solutions market size is set to exceed US$2 billion by 2025. By region, the study finds Asia Pacific is expected to grow at the highest compound annual growth rate of around 20 percent in the PoE solutions market due to many countries, such as China and India, promoting the adoption of internet of things across various industries.
Further, Global Market Insights forecasts a compound annual growth rate of 15 percent for the segment of powered devices, which include VoIP phones, access control
systems and of course IP cameras amid the IP trend in video surveillance. For today’s network cameras, each has a PoE port that connects to the internet via a Cat5 or Cat6 cable, through which both data and power are delivered.
The benefits of PoE video surveillance systems are manifold, the biggest of which is obviously the convenience factor as well as the time and cost savings, as the camera can draw power directly from the PoE switch that it is connected to, thus eliminating the need to get a separate power cable. Installation can also be done much faster with lower cost, saving end users more money. Plus, with no extra power lines required, more flexibility can be achieved for the end user, who can place the IP camera in the most suitable location, without taking power source into consideration.
Another major advantage is data speed. “With the need for faster upload and download speeds, as well as reliable connectivity, there is a growing need for faster data speeds. PoE delivers that — systems can deliver up to 1Gbps using both Cat5 and Cat6 Ethernet cables,” stated CCTV Security Pros in a blogpost
. “The new IEEE 802.3bz standard now provides faster data speeds of up to 2.5Gbps to 5Gbps over distances of 100 meters with an immediate view to reaching speeds of 10Gbps. Most HD streaming requires around 400Mbps for seamless performance, so PoE technology offers more than enough data speeds to support surveillance network connectivity and live viewing in local area networks of computers and other associated devices like PoE CCTV security cameras.”
While PoE brings lots of advantages to the video surveillance system, there are certain things that the installer or user needs to beware of. One thing in particular is power budget, or the total power needed at a particular site. This is something that needs to be considered during the system design process.
The current PoE standards, IEEE 802.3af and IEEE 802.3at, specify output of 15.4 watts and 30 watts, respectively, from each port of the PoE switch.
Basically, calculating the power budget boils down to the number of cameras at the site and the power consumption of each camera. For example, if there are eight 15.4W cameras and two 30W cameras on site, then the total budget will be 183.2W. The user therefore needs to get a 10-port power-over-Ethernet switch capable of supplying 183.2W of power.
But more and more, there are cameras that consume more power than 30W. Some cameras, for example, have heaters/blowers inside to keep them either cool or warm in specific conditions. When turned on, they can draw more power than the current standards allow. To meet this requirement, the user may need to purchase Ethernet switches with 60W ports.