4.1.19 – SSI –
The capability to run electric power over Ethernet cabling continues to facilitate the revolution of networked security devices. Here’s how.
Prior to the advent of a formal standard for Power over the Ethernet (PoE) in 2003, IP cameras and other edge devices typically required power supplies at the location where they were deployed.
The formalization of a PoE standard dramatically changed conventional design and installation models while greatly reducing equipment and installation costs, and enabling a highly efficient means to expand IP-based security and surveillance systems at the edge.
In recent years, PoE has continued to have an enormous impact across the professional security industry. In fact, the advent of PoE has stimulated R&D and accelerated the development of new and innovative power and transmission solutions.
The basic idea behind PoE is quite simple and ingenious: use a single Cat-5 cable to deliver power and pass data to electronic devices such as IP cameras and accessories, wireless access points, and telephone and intercom systems.
The very first PoE standard, IEEE 802.3af, provided for up to 15.4W of DC power per port. Of that 15.4W, approximately 13W is typically delivered to the powered device, because some power dissipates in the cable.
As new and higher performance IP surveillance and security products were developed to take advantage of PoE, so did the demand for a PoE standard that would allow higher wattage loads.
Because of the low wattage limits of the first PoE systems, some device manufacturers had begun using more than one PoE port to power a single device.
In 2009, the Ethernet Alliance, a global consortium dedicated to the continued success and advancement of Ethernet technologies, ratified the IEEE 802.3at PoE+ standard to satisfy the need for higher wattage loads.
PoE+ supports up to 25.5W of DC power to edge devices and prohibited the practice of using multiple ports. In addition to the increased power that IEEE 802.3at PoE+ standard provided, it also delivered environmental benefits.
According to research from the Ethernet Alliance, it is significantly more efficient to power edge devices requiring 25WDC with PoE+ versus multiple PoE sources.
The estimated increase in power efficiency jumps from approximately 85% to 92%, directly reducing the global carbon footprint of organizations around the world.
New products continue to come to market faster than ever, and many of the edge devices, including multisensor megapixel cameras, require more power than the output of IEEE 802.3at PoE+ rated power supplies.
Add accessories like infrared illuminators and environmentally controlled enclosures, and the power demands of these new edge solutions tend to surge even higher.
This increasing power requirement stimulated an industry call for PoE solutions that could deliver power in excess of the IEEE 802.3at PoE+ standard.
As an example, Altronix released its NetWay Midspan Injectors and eBridge Ethernet over Coax (EoC) solutions capable of delivering up to 60W per port with fast data rates over long distances.
With its widespread acceptance and proof of performance, this technology established an industry de facto Hi-PoE standard of sorts.
Meet New IEEE 802.3bt Hi-PoE Standard
In October 2018, the Ethernet Alliance announced the ratification of the IEEE 802.3bt Hi-PoE standard, which boosts PoE product output by a factor of three from 30W to 90W, and elevates the power level for powered devices to 71.3W.
This standard offers myriad new features and capabilities, including support for highly efficient four-pair power delivery, with channels for 2.5, 5 and 10Gbps data transmission.
These new power and transmission capabilities have far-reaching effects that can further accelerate the deployment of IP devices across numerous applications above and beyond professional security.
Another significant benefit of IEEE 802.3bt Hi-PoE is its ability to help future-proof networked systems by providing a power and data transmission foundation to accommodate new and emerging IP solutions.
It also allows system designers and installers of IP systems to easily identify compatible products when deploying integrated systems, thereby selecting increasingly divergent products and system solutions from different manufacturers.
There’s no doubt that IEEE 802.3bt Hi-PoE compliant products are, and will continue to be, extremely beneficial for numerous applications and system configurations, providing the technology is properly implemented.
The following are four key factors to consider…
Properly Estimating Power Consumption
It’s easy to underestimate the aggregate power consumption of PoE security devices when designing and installing a system. The number of edge devices on a system can quickly add up when there are multiple IP cameras, access devices, wireless modems and other devices deployed.
With the additional power that Hi-PoE power solutions are capable of providing, edge devices of all types can incorporate more embedded features and functions, and integrate with more accessories, enhancing performance without taxing network infrastructure.
Consequently, it’s critical to carefully calculate the amount of power required to properly sustain all devices simultaneously, and how those power requirements are distributed across the network.
Don’t Forget About Voltage Drop
While the total output of Hi-PoE is technically 90W, it’s crucial to account for voltage drop along Cat-5E or -6 cabling by taking into account distance limitations.
To help ensure edge devices receive the power they demand, it’s best to use a voltage drop calculator (an easy source can be found at altronix.com/public/calculators/).
As cool as Hi-PoE sounds, not every application demands Hi-PoE. The most ideal applications for Hi-PoE typically involve outdoor installations employing high resolution megapixel cameras, heavy-duty pan/tilt/zoom systems and any device that may require an environmentally controlled enclosure.
Powering more powerful heaters/blowers with PoE+ required a separate power supply, which called for higher equipment, infrastructure and installation costs.
The new Hi-PoE standard can easily supply the power these devices require with much higher levels of cost efficiency.
This also opens the door for the development of new products that could require more power. The same holds true for IR lighting. Because of the power limitations of PoE and PoE+ systems, the only way to integrate high-intensity IR illumination in those systems is by using an external illuminator with a separate power source.
In contrast, Hi-PoE solutions will provide the required power for most IR illuminators without added infrastructure or equipment or costs. This also allows camera manufacturers to embed higher-intensity illuminators into their products.
Proper Equipment Selection
A number of mid-span injectors on the market provide Hi-PoE functionality, but most are manufactured for indoor use. This means they are incapable of operating adequately in outdoor situations where long distances and harsh conditions present a multitude of challenges.
For successful Hi-PoE deployment outdoors, it’s critical to use an injector that is designed specifically to withstand the elements and provide adequate power.
There are a seemingly unlimited number of system applications that will benefit from the deployment of Hi-PoE technology. The ability of Hi-PoE to efficiently deliver more power and fast data transmission rates over extended distances to edge devices allows system designers and manufacturers to increase the capabilities of IP cameras and other system products without significantly increasing costs.
Ronnie Pennington is National Sales Engineer for Altronix Corp. Contact him at firstname.lastname@example.org.