TCO Analog and IP based video surveillance

This Axis Communications white paper compares the total cost of ownership (TCO) of 14, 25 and 40 camera analog and IP-based video surveillance systems. I found the following statement interesting:

“One of the longest-standing arguments against going all-digital has been the perceived higher cost of IP cameras compared to their analog counterparts. However, cameras are only one part of a video surveillance solution, and the total cost of a complete system is dependent on a number of factors.”

Are IP-based systems able to compete with analog products for small to mid-sized projects?  Have digital solutions reached a market tipping point and will they capture a majority of the surveillance market anytime soon?  Read the whole thing

High Power PoE Test Drive

Today’s lab work included testing the combination of the Microsemi (Power Desine) PD-7001G 30 watt mid-span PoE power injector and the same company’s PD-AS-701/12 30 watt high powered PoE splitter. These devices are well suited for use with cameras like the Axis 215 PTZ which require less than 25 watts but more than the 12 watts available from 802.3af systems.

Our real-world testing included a pair of the above devices plus a Kill-A-Watt AC power meter, a 12 ohm 50 watt load resistor, a DC ammeter and a DC voltmeter. Results as follows

AC Power – 15W @ no load, 30W @ full load
AC Volt-Amps – 27VA @ no load, 48 VA @ full load
DC Voltage 12VDC @ no load, 11.85VDC @ full load
Load Test Current 1.85 amperes
Load Power 21.9 Watts
Overall efficiency 73%
Injector Final Case Temp ~100F
Splitter Final Case Temp ~120F

These devices require free air flow and should not be buried under any type of insulation or barrier. The power available is more than sufficient for the Axis 215. Here is a good table of applicability of high power PoE to various Axis cameras. This table suggests that the 701/24 can provide power for the even larger 232D+ or 233 PTZ cameras. Do bear in mind it will NOT run the heater/blower in an outdoor dome.

Power over Ethernet – Plus

Most new IP based security cameras allow for Power over Ethernet (PoE) operation and this is now established as a way to reduce installation cost while improving reliability and easing management’s job. Since 802.3af PoE is limited to about 12 watts maximum load, the operation of PTZ cameras is generally considered beyond the scope of the method. While the pending higher powered 802.3at standard is still but a future promise, all is not lost.

Many of the newer PTZ cameras (such as the Axis 215) can be run on DC power and require less than 25 watts. There are several companies (such as Power Designs and Phihong) that offer external (midspan) power injectors and splitters that can easily deliver enough power for such cameras.  The site Power Over Ethernet is a good resource for information on this equipment.

We have completed several project designs using these high powered PoE systems with good results and large savings in installation costs.  Keep this idea in mind for your next design or installation.

Wireless – Less is More

The installation and use of commercial quality long range point-to-point wireless network links provides great flexibility in IP camera deployment but is generally associated high cost and somewhat challenging technical problems.

We have recently engineered several wireless IP camera installations using the EnGenius 3220 series of high powered outdoor wireless AP/Client Bridge equipment. While there are many better-known makes, we find the 3320 series offers these advantages:

-Models with 5dBi omni, 9 dBi patch, and 16 dBi patch antennas built-in.
-Low cost, around $150 per unit which is the low end of the general price range.
-Simple installation and set-up, point-to-point or point-to-multipoint.
-True 802.af Power over Ethernet (PoE) operation (many use a non-standard PoE).

The available antenna configurations are very flexible, good mouniting brackets are included, and PoE injectors and power supplies are included, making for easy installation. The built-in antennas eliminate the need for RF cables and potentially leaky connectors.

A lesson we learned the hard way is that when the path is relatively short (100 to 500 feet), the units should NOT be run at full power. The high output of the radios causes overload which actually prevents proper operation.

Trees in the LOS (line of sight) path do reduce range. The units have a web page based signal strength indication which helps with antenna alignment but lack any external readout. The 16 dBi unit has a half-power beamwidth of 30 degrees while the 9 dBi offers 60 degrees.

This equipment is available from specialty reseller DoubleRadius and other more general distributors.