Power over Ethernet (abbreviated PoE) is a term that gets thrown around a lot. Most Ethernet cables today are made PoE ready, but what exactly does that mean? What can PoE be used for and how is it different from other options used to accomplish those same tasks? This article will examine what PoE is, its uses, and how well it holds up compared to other modern-day technology.

What is Power over Ethernet (PoE)?

To understand PoE, start by thinking about how Ethernet cables work. At the core of every Ethernet cable, there is are lines of copper that run down the length of the entire cable. Ethernet cables transmit electrical signals that are interpreted by computers and other electronics as the 1’s and 0’s that make up binary code. The takeaway here is that Ethernet cables have always been capable of transmitting electricity since their invention. PoE just takes that function and moves it in a similar but slightly different direction.

PoE was first developed by the company Cisco. Up until this point, every electronic with Ethernet needed two cables: the Ethernet cable itself and another cable for power. A lot of IT workers were annoyed by this since not every electronic they worked with was near an outlet or another power source. Cisco’s solution to this issue was supplying power through the Ethernet cable, making PoE cables an all-in-one solution. In 2003, PoE was standardized by the Institute of Electrical and Electronics Engineers (IEEE) and started to see widespread use across the IT industry shortly thereafter.

What uses Power over Ethernet (PoE)?

While PoE is an innovative solution, there are limits to its capabilities. Compared to a conventional power cable, Ethernet does not have much metal in its inner workings (the conductors). This means that PoE is mainly used for small devices that do not need much power. Electronics like VoIP telephones, security cameras, digital signs, and laptops can all get power from a PoE connection whereas larger devices like desktops and servers cannot.

There are different types of PoE available as its technology has improved over the course of the last 16 years. The exact wattage supported by a PoE cable may depend on its age, as most cables on the market today are simply made to the newest, highest standard of PoE.

  • Type 1 - 15.4W
  • Type 2 - 30.8W
  • Type 3 - 60W
  • Type 4 - 90W

Writing on the outside of the cable should indicate which type of PoE standard the cable was built to. It may also show an IEEE number, which can be viewed via the IEEE website linked above, depending on the cable’s manufacturer. All forms of PoE are built with safety measures to prevent excess electricity from damaging connected devices, but an older cable could simply not work if it carries less wattage than the connected device uses.

In addition to these standard PoE cables, Digital Lightning Management (DLM) cables have also recently entered the market. This new breed of PoE is designed to minimize electricity usage to save on energy costs. DLM cables are used on common office devices such as light switches, overhead lighting, occupancy sensors, and other equipment connected to a digital controller that manages system settings. The cable jackets are also plenum rated, ensuring that DLM cables are ready to meet safety standards in the event of a fire.

Why use Power over Ethernet (PoE)?

The first reason to consider PoE is ease of access. Regular power cables are large, thick, and harder to pull through walls and conduit than Ethernet. Using Ethernet to get to these hard-to-reach places also eliminates the need to run two different cables to remote devices like security cameras.

The next big reason is reduced costs. Almost every Ethernet cable is made PoE ready today and Ethernet cables are practically a dime a dozen. Since different categories of Ethernet cable only determine data speed, not wattage rating, sticking with the least expensive option (Cat5e) is no issue when providing power is the main concern. Additionally, running a separate cord for power typically means having to install a new power outlet somewhere. Using PoE eliminates that cost on top of removing the separate power cable from the equation.

The only real limitation of PoE is the amount of power it can provide. For electronics with small power requirements like a TV screen or a wireless access point (WAP), a PoE cable is more than adequate. But devices with higher power consumption like desktop computers cannot run off a PoE cable alone. At least not yet, as the technology is continuously improving.

Upgrade to Power over Ethernet (PoE) Today

All of the Ethernet cables here are ShowMeCables are PoE ready. We also carry switches, splitters, injectors, and other devices designed to convert older, non-PoE networks over to PoE standards. Whether PoE is an old or new concept for you, ShowMeCables is ready to lend a hand today.

Have questions about PoE or any of our other products? You can reach our Sales team at 1-888-519-9505 or Sales@ShowMeCables.com