Operation Concerns
PoE Dome Controls
PoE or high PoE simplifies installation, as it eliminates the need for a separate power cable. “Only one standard Cat-5 cable is needed for carrying power, as well as video and PTZ controls,” Frannlid said. Standard PoE (802.3af) is about 15 watts, while high PoE (802.11at) goes up to 30 watts.
The limited power from standard PoE is insufficient for driving most pan-tilt dome motors. “IP manufacturers are increasingly making domes work at lower power consumption,” Pigram said. “They're not quite fully functional and tend to be for internal use.”
Outdoor PTZ domes area
challenge for PoE, due to range and power requirements. “We see PoE and high PoE as very useful for indoor junior domes but of limited use outdoors, due to the power needed to run heaters and the losses due to the distance from the power source,” Crosby said. Heated domes could use as much as 50 to 60 watts — power that PoE cannot deliver yet. Finding the right network switch for standard PoE is not a problem, but gets trickier for high PoE. “There are PoE solution vendors who provide higher power through nonstandard solutions, but those are not as easy to obtain as a standard solution and are generally cost-prohibitive,” Corrall said.
Intelligent Networks
Along with transmission, smooth dome operations depend on network infrastructure. “You must design the network efficiently so you don't get problems with latency,” Pigram said. This means the right storage solution is used so users can record according to their needs.
Network domes enable more
management options, depending on operator preference. Dome controls should integrate a user-friendly interface. “Some have virtual keyboards on the screen; some people integrate analog keyboards; and some are happy with a mouse to click on the screen,” Pigram said.
As IP replaces analog, there is less reliance on traditional methods of controlling cameras with keyboards and joysticks. “With higher resolutions and integration with other security systems — like access control, analytics that can detect and alarm on predefined events, and faster access to recorded video — there is less need to actually have a person watch video screens, and customers are, therefore, changing the way they interact with their security systems,” said Dave Stanfield, Senior Product Marketing Manager at Pelco (a Schneider Electric company). “Having said that, there are still applications where real-time monitoring is important. In those cases, we continue to see the need for very precise, low-latency controls afforded by analog capabilities. These applications typically result in a hybrid system that is digital on the recording side, but analog on the control side.”
Advances in processing mean analytics are becoming a standard feature for network domes. “Motion, tamper, movement, trip wire — those kinds of detection will be built in,” Pigram said. However, false alarms make analytics helpful but not a must-have.
Video analytics should be critically evaluated. “Analytics-driven alarming has to be very carefully applied and should not be the only source that one relies upon in critical environments,” Stanfield said.