Power Play

March 24, 2011

What comes to mind when you ask “What do CCTV, access control, intercoms, doors, contact closure modules all have in common?” One possible answer is IP connectivity. Now, you can add the ubiquitous power supply to the list. One company at least — Life Safety Power — has made IP-based features a signature element of its product line, and, given the likely advantages, I expect more to follow.
Before you start shaking your head in bewilderment, think of the predictions for everyday items in our lives moving to IP — refrigerators, toasters, utility meters, etc. Reasons I have heard include device control, supervision, upgrade, preventive maintenance and avoidance of catastrophic failure. Sounds like some of these might be useful when applied to a power supply product. Incorporating some of Life Safety Power’s ideas and carrying them forward, here are some ideas to think about.
Form C contacts have been around since the dark ages — extensively used, reliable and necessary, a bit like analog video in the surveillance industry. It is well within today’s design technology to pull critical data from power supply circuitry. In addition to AC input or DC output failure and low battery supervision, there are numerous other monitoring possibilities, including actual voltage levels and their variability over time; current draw per output circuit; actual battery voltage and trend data; charging current; battery age and history; fault history and tamper events. All could be reported via SNMP or e-mail. Since power supplies are the lifeblood of most devices, timely e-mail and text reporting of device status can resolve problems quickly or prevent problems from occurring through pre-emptive action.
If you can program the parameters for an IP camera, shouldn’t you be able to do the same thing for a network-connected power supply? And if you could, what parameters matter? If an area is prone to intermittent faults, a programmable threshold where a fault persists for a period of time before reporting could eliminate excessive nuisance reports. Given the importance of back-up batteries, programming a notification frequency for battery replacement consistent with security department policy will lead to timely action.
Similarly, connectivity provides the potential means to control the power supply and, potentially, devices connected to it. In its most flexible form, an IP-controlled power supply could be remotely re-booted, where individual outputs are selectively toggled to allow a hard reboot of a connected device such as a CCTV camera. For an organization tasked with performing remote supervision and maintenance, it is an opportunity to reduce truck rolls through a remote reset capability and better leverage their monitoring services.
Once the capability exists to remotely actively interact with power supplies, a range of other possibilities becomes possible. Information could be fed to Physical Security Information Management (PSIM) and Video Management Systems (VMS). In A PSIM application, loss of power to one or more devices could then be correlated with an external natural or man-made event. Based on location of the devices losing power, inference on the overall power status in an area and connected devices could be determined. In a VMS application, loss of video could be correlated with lost power, speeding the troubleshooting process.
Also, new network mapping and diagnostic programs will eventually be integrated with the IP- and SNMP-based features of intelligent power supplies to get a view of the low-voltage network and connected devices, effectively creating a low voltage power map of an installation. As the industry goes “green,” knowing consumption, plotting trends over time and identifying problems should ultimately enable tighter control.
Maintenance policies can be revised to change batteries based on performance degradation rather than time — saving both time and material costs. Performance-based criteria can lead to new preventive maintenance approaches. Coupled with new intelligent infrastructure products, information could be correlated to develop approaches to respond to disconnected power, disconnected switch ports and door alarms in communications rooms.
Certainly, these concepts can be extended into the world of IP devices. How do IP devices meet the UL requirements for battery back-up when power is provisioned by a PoE switch or mid-span injector? Although technically not required by the UL 2294 standard for access control, if power back-up is employed, should it not meet the four-hour UL requirement?
IP cameras have become smarter with the addition of embedded analytics, and they will become more so as analytics capabilities grow. If cameras are used to detect smoke, there is an argument that can be made for meeting UL 864 and 1481 fire standards. So follow the chain from IP camera to mid-span injector or PoE switch to UPS. Does the back-up system meet the associated 24-hour requirement?
Similarly, IP cameras with motion detection — powered the same way — might be called intrusion detection devices. Will they not be subject to UL603 and 1076 burglar alarm standards? Certainly food for thought. What is clear is that the ability to understand what is happening in the low-voltage network and to act preemptively or to respond quickly is attractive indeed.

Ray Coulombe is Founder of SecuritySpecifiers.com, the industry’s largest searchable database of specifiers in the physical security and ITS markets; and Principal Consultant for Gilwell Technology Services. Ray can be reached at [email protected] or through LinkedIn.