Power over Ethernet (PoE) technology has been utilizing Cat 5e and Cat 6 Ethernet cables to deliver electric power alongside data over a single connection for years. This innovative technology enables safe and efficient installations that effectively transmit power while collecting data, all at a reasonable cost.

Key Applications of PoE

PoE powers a variety of devices, including VoIP phones, wireless access points, LED lighting systems, surveillance cameras, industrial controls, and network switches, using just one Ethernet cable. PoE is responsible for powering at least a third of Internet of Things (IoT) devices, which number in the billions today. Smart homes, IP security systems, digital signage, and monitoring sensors in industrial settings all leverage PoE technology. One of the primary advantages of PoE is the significant labor cost savings achieved by eliminating the need for separate electrical lines and outlets for each powered device. Many users also prefer PoE for outdoor connections since it is safer than standard electrical cabling.

Limitations of PoE

Despite its advantages, PoE does have some limitations related to transmission distance, device compatibility workarounds, and power delivery rates. The maximum transmission distance for PoE is limited to 100 meters (approximately 328 feet), which can be inadequate for many users’ needs. This limitation does not stem from the powered cable itself; rather, it is influenced by the test equipment used during installation. Testers are designed to assess only up to 100 meters and will indicate a failure if this limit is exceeded, even if the signal continues beyond that range. Thus, limitations on PoE distance arise from Ethernet cabling standards and testing equipment as well as the quality of the cables used.

How Far Does PoE Cable Work?

A single PoE cable has a distance limitation of 100 meters, but the question of how far does PoE work can be answered with some flexibility. PoE can power any device at varying distances, as long as sufficient power is generated at the source to operate the unit on the other end of the cable run. The actual distance a PoE cable can effectively run depends on the voltage required to operate the powered device and the quality of the cable itself. Most users typically rely on a Cat 6 cable for longer runs and a Cat 5 cable for shorter ones. For a short run, the power supply usually needs to be 24V, while a long run typically requires 48V. If these voltage requirements are not met, the cable will not carry enough power to operate the desired device.

Do You Need Special Cables for PoE?

Regular and PoE-enabled local area networks both use the same kinds of cables, so special cables are not required when using PoE technology. Usually, a Cat 5e or better standard cable that includes four twisted pairs of copper cables will work. For comparison, electricity only needs two pairs of cables—a negative pair and a positive pair.

PoE cables also need temperature ratings higher than 60 degrees Celsius. Acceptable cables come in 60-, 75-, or 90-degree ratings, with the ratings referring to the temperatures the insulation can withstand. A higher-rated cable can power a larger device, as it can effectively withstand the heat generated by the additional power transmission. Acceptable cables may also use different conductor sizes. As with the heat ratings, the bigger the conductor, the more power the cable can relay.

What Wires Carry Power over PoE?

The magic of PoE is basically this—the wires within the cable can carry data and power simultaneously without you as the user needing to modify the existing Cat 5 Ethernet infrastructure. With 10Base-T and 100Base-TX cables, two of the four wires get used. This means power moves along the same wires as data, similar to the phantom power technique in which a common voltage gets applied to each pair. In 1000Base-TX cabling, sometimes referred to as gigabyte Ethernet, all four wires transport data.

What Is a PoE Extender?

If you need to run Ethernet LAN signals farther than 328 feet, one option is to use a PoE extender. These were developed in 2005 in order to extend long-distance power to devices such as PoE Wi-Fi access points and PoE IP cameras. Consumers liked these extenders because they helped lower the cost of installing PoE Ethernet devices. PoE extender solutions usually stretch up to about 4,100 feet from your source, or more than 12 times as far as a single cable alone. Fortunately, PoE extenders are not difficult to use. In general, it’s just plug-and-go technology. The extenders usually work so seamlessly that the user may never know it’s there.

Problems with PoE Extenders

While PoE extenders seem to be a great solution, one significant issue related to their use is the addition of another termination point (connector) to the channel. This can create one too many points in the channel, resulting in excessive noise and insertion loss, which will degrade the signal and render the cable inoperable.

BICSI installation standards are defined by TIA/EIA-568-C, which defines a limit on the number of connectors used in the channel between the MDU (rack) and the connected device. 

What About Powered Cabling Solutions?

A newer trend to extend distances beyond PoE’s standard limit involves using powered cabling solutions instead of extenders. Remee Wire & Cable offers Activate™ Powered Cable Solutions designed specifically for this purpose. These hybrid copper and fiber optic cable configurations work seamlessly with Ethernet networks across various settings where extenders may not be feasible—such as large buildings or government facilities—where Daisy chaining connectors could lead to insufficient power levels.

Remee’s solutions include Cat 5e cables capable of carrying 15.4 WPS, Cat 6 and Cat 6A cables carrying up to 30 WPS, and Cat 6 Limited Power for PoE++ supporting either 60 WPS or 100 WPS. These cables come with or without shielding and PVC jackets for added protection. The top-performing cables can carry up to 100W of power while also offering options like water-blocking and direct burial versions.

Remee utilizes composite cable and Siamese cable designs to extend distances for hybrid data and power applications. Composite cables combine copper conductors (12 AWG to 18 AWG) with fiber optic strands for enhanced data transmission alongside additional power capability. Siamese constructions consist of two insulated stranded bare copper conductors paired with fiber optic cable to facilitate both data and power beyond the standard limit.

Understanding PoE Distance

When considering PoE distance, it’s crucial to note that while individual runs are limited to 100 meters due to standards set by IEEE specifications, innovative solutions like powered cabling can help overcome these limitations effectively.

Learn More About Powered Cabling Solutions

Remee’s Activate™ Powered Cable Solutions encompass various options including PoE cables along with hybrid composite and Siamese cables designed for extended distances. To better understand your specific application needs regarding PoE capabilities, consult Remee’s distance/bandwidth chart, which visualizes power distance requirements along with data distance metrics.

For more information on PoE or powered cable solutions—including advantages, limitations, benefits, and standards—check out Versatek’s article titled “What is PoE?”