Introduction to Power over Ethernet

Introduction to Power over Ethernet
A breakdown of what PoE is, why you might use it, and potential considerations

Power over Ethernet (PoE) has long been linked with IP cameras, VoIP phones, and the like. Increasingly, though, the technology’s being adopted in more areas of traditional building automation. There’s even talk that PoE will drive the smart buildings of the future. Your building might already have lighting controls and fixtures, access control systems, and sensors or meters running on PoE. 

What is Power over Ethernet? 

Normally, you need separate cables to provide power to devices and connect to device data. Power over Ethernet is, simply, a method for both powering devices and driving data, all using a single cable. 

Check out how PoE differs from non-PoE connections.

 

Introduction to Power over Ethernet

Source: Veracity Global

How does it work?

Power over Ethernet uses one cable made up of four twisted pairs to send and receive data, and to power devices, according to Veracity Global. In 10 and 100BASE-T Ethernet, two of these pairs are treated as “data pairs” while two are unused and treated as “spare pairs.” In Gigabit Ethernet, all four pairs are used and none are treated as spares. 

Between these four twisted pairs, PoE has all it needs to both conduct electricity and pass data traffic. “Because electrical currents flow in a loop, two conductors are required to deliver power over a cable. POE treats each pair as a single conductor, and can use either the two data pairs or the two spare pairs to carry electrical current,” explains Veracity Global.

Why use PoE? What are the benefits? 

As mentioned, there’s been lots of talk about PoE being ideal for adopting smart building technology. That’s because PoE provides fantastic flexibility and scalability, as well as time and cost savings. 

  • Flexibility: Given that PoE doesn’t require electrical outlets, devices can be deployed anywhere, and can be repositioned easily too. 
  • Scalability: This also means that growing the network is simplified, with straightforward installation and no power access constraints. 
  • Savings: PoE reduces the amount of money spent on electrical cabling and, because the cables don’t need to be installed by an electrician, they also reduce labour costs. 

Additionally, PoE can drive different power types. For example, Cisco came out with UPoE, which is 60 W, and UL is creating a standard for 90W. This increases the worthiness of the devices in the field because you can simply power more, different types. 

Lighting can be powered through a single LED light with 30W, but 60W can give you four. This lowers the amount of home-run cable required, which is typically the biggest concern about PoE. 

What are some disadvantages to consider?

There have been lots of misconceptions about PoE over the years, like that installing it requires electrical training, or that there are compatibility issues.

While these misconceptions aren’t something to worry about, there are some potential issues that MV Team shares, mostly related to reliability and redundancy. If one PoE switch experiences delays or issues, any devices connected to it could be affected. Accordingly, they recommend a separate power supply if reliability is a concern. 

While there are many advantages to PoE, these are some concerns to consider when designing the network and selecting devices. 

What are some examples of PoE installations?

There are many different devices that can run over PoE, including surveillance cameras, lighting, wireless access points, access control, and more. 

A couple of great PoE installation examples come out of Australia, at 25 National Circuit and 45 Benjamin Way. By integrating PoE into these retrofits, Optigo Connect and Delta Building Automation reduced costs and limited disruptions to existing tenants. 

Learn more about these projects! Download the 25 National Circuit case study, and check out our webinar and blog post. You can also download the 45 Benjamin Way case study, and check out our interview with Hendra Nugraha, the National Engineering Manager at Delta Building Automation

Recent Blog Posts

Visual BACnet’s Advanced Reports are a fantastic addition to your service offerings, and a great way to keep your network updates on track. 

You can use them to:

We are proud to share that we’re the exclusive building networks solutions partner for Alerton’s Strategic Partner Program.

One of the biggest barriers we’ve found in this industry is a lack of accessible educational resources. For people who are new to the business of BAS, it’s a real challenge trying to string together information.

There are goblins and ghouls that go bump in the night; and then there are BAS misconfigurations that give you a fright! For the last few Halloweens, we’ve collected some of your spookiest network horror stories. Read on for stories of:

What’s the problem with a “one-size fits all” solution? It usually fits nothing. 

Recent Projects

Data center expansion with OTI and Optigo Connect

DATA CENTER EXPANSION

Stack Infrastructure is a portfolio of hyperscale computing data centers. OTI completed work on Phases I and II, and returned for the Phase III build-out of a 4-megawatt data hall and brand new central plant. The Optigo Connect network put in place in Phases I and II was expanded on this project. The team achieved quick roll-out of a large, multi-service redundant network using the Optigo OneView management interface. Going forward, the facility management team can use OneView to remotely monitor equipment, manage power usage, and meet up-time goals.

Optigo Connect MR Soluciones The Landmark

THE LANDMARK

The Landmark is a sophisticated mixed-use high-rise in Mexico. The owners wanted to integrate all OT systems in the skyscraper, while maintaining separate networks for each application. The Landmark is the fourth joint project between Optigo Networks and MR Soluciones. Together, these companies provide robust services to meet any challenge.

Australian Bureau of Statistics at 45 Benjamin Way with Delta Building Automation

45 BENJAMIN WAY

Delta Building Automation (Australia) had a big job renovating the Headquarters for the Australian Bureau of Statistics (ABS) at 45 Benjamin Way. The building owner wanted to improve the building’s energy use and increase their National Australian Built Environment Rating System (NABERS) score to more than 4.5 stars, out of a possible total of six. Securing the network both internally and externally was a big priority, as well.

Penn State University Optigo Networks Visual BACnet

PENN STATE UNIVERSITY

When Tom Walker looked at Penn State University’s Navy Yard network, he saw huge issues. The system was busy and loud, to the point where the overrun network was bringing down the entire building. Because this was happening on the MS/TP network, pinpointing the problem would mean boots on the ground to segment and test the chain, piece by piece.

Penn State University Optigo Networks Visual BACnet

PENN STATE UNIVERSITY

When Tom Walker first started working at Penn State University four years ago, there were a lot of network issues. Buildings were dropping offline. Broadcast traffic was pushing 90,000 packets per hour. Walker was on the phone almost every single night because devices were down or had to be reset.

 

Torre Manacar Mexico City Optigo Connect

TORRE MANACAR

When MR Soluciones began work on Torre Manacar, they knew they needed a flexible and scalable network infrastructure to support a wide array of integrated systems. Optigo Networks was a natural fit for the massive project, designing a robust network at a competitive cost.

short

SHORT PUMP TOWN CENTER

Short Pump Town Center, an upscale retail center, underwent a complete renovation in 2014. The flexibility of Optigo Networks’ solution meant the retail center’s unknown final design was not a barrier to placing IP surveillance equipment in the field.

BOULEVARD MALL

BOULEVARD MALL

Optigo Networks connected New York-based Boulevard Mall’s security surveillance devices in December 2015, using a Passive Daisy Chain topology.

Visual BACnet tech support team

TECH SUPPORT TEAM

One tech support team at a manufacturer purchased an account with Visual BACnet in April 2017, for technical problems around the world.

Aster Conservatory Green Optigo Connect

ASTER CONSERVATORY GREEN

The Aster Conservatory Green is a community comprising 352 residences across 24 low-rise buildings. The buildings use advanced surveillance and access control technology, including 40 HD video cameras and 60 FOB-access-tele-entry points for access control.