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Power over Ethernet, or PoE, is a popular Ethernet technology that transfers data and electrical power simultaneously over a single cable. Standard Ethernet can only transfer data and is ubiquitous in all networks from home, business, and data centers.

A PoE network consists of Power Sourcing Equipment (PSE) that supplies electricity to Powered Devices (PD). Ethernet switches with PoE ports are a type of PSE powering PD devices such as IP cameras, wireless access points, phones, and sensors. The watts consumed by the PDs connected to a port of the PSE cannot exceed the maximum wattage supplied by the PSE.

Sometimes, you will encounter an application where you must connect a PoE device, like a camera, to a network incompatible with PoE technology. In this situation, a device called a PoE injector is used. This convenient device accepts a standard Fast or Gigabit Ethernet input and outputs data and power on a PoE port, eliminating a separate power cable to the PoE-enabled electronics. PoE injectors can be set up quickly and easily, freeing up your valuable time so that you can focus your attention on high priorities. This technology provides a wide array of benefits.

What are the Benefits of a PoE Injector?

• Using a traditional Ethernet cable, they connect a basic Ethernet switch to PoE-compliant devices.
• They reduce the need for a separate power cable to be connected to the device, so there is no need to locate a nearby AC outlet.
• They help save money, space, and installation time.
• They can add new devices to existing legacy networks improving scalability.

How Do PoE Injectors Work?

Think of a PoE injector as a “middle man” between two components: a non-PoE compatible network switch and an external device like a PoE camera. Power is added to the Ethernet cable at the connection point, meaning any connected device which meets the IEEE 802.3 PoE standards (af, at, or bt) is adequately powered.

PoE injectors provide DC power to devices considered “low power” – most only require 15 watts or less for operation. Although, the PoE standards accommodate devices requiring up to 30 and 60 watts. PoE injectors are commonly employed to connect and power devices in areas with limited access to or without conventional power outlets.

Due to their versatile nature, many PoE injectors are installed in manufacturing or industrial environments like factories and outdoor locations. Because of this, they come with rugged features that stand up to harsh conditions. For example, industrial-grade PoE Injectors:

• Are packaged in a rugged DIN rail mount enclosure.
• Operate successfully in wide temperature ranges.
• Are resistant to shock and vibration.
• Offer superior protection against electrical noise.
• Protect against current and voltage overloads.

The Major Benefits of PoE Injectors

One of the significant benefits of a PoE injector is that it eliminates some of the complex cabling typically required in network installations. In most situations, you can use a regular Ethernet cable to connect from the local area network (LAN) switch to the PoE-compatible device you’re working with. Eliminating an additional power cable that would otherwise be required offers fast, efficient deployment reducing costs in a situation where you need to make every dollar count. Power cabling is inherently expensive – not to mention that it takes up a significant amount of space. All of these pain points can be eliminated with the use of PoE injectors because Ethernet cables themselves are neither expensive nor bulky.

One particular benefit of PoE injectors comes by way of the manufacturing industry. In many of these organizations, space is always at a premium. You may have limited access to the area needed where you could begin a new installation for the new required cabling. However, fresh technology can be integrated into your network with a PoE injector. So rather than spending time, money, and energy on building a new network (and mitigating the risk that always comes with that), you can simply extend your existing one and achieve the same results.

There are other benefits of PoE injectors as well, which include but are not limited to ones like:

1. Thanks to various power configurations, PoE injectors offer superior flexibility to even complicated networking environments.
2. There is no longer a need to maintain a separate power supply exclusively for powering cables as required in a more traditional PoE deployment.
3. PoE injectors comply with the strict IEEE 802.af/at/bt standard and are designed to avoid damage to connected devices – even those not PoE compliant.

Regardless of the type of application you’re working with, the chances are high that your network infrastructure can benefit from at least a few of the features the right PoE injector has to offer.

Additional Considerations About PoE Injectors

When selecting a PoE injector, you’ll have two types to choose from: active and passive models. Through handshaking, an active PoE injector discovers more information about the connected devices’ current flow. It then matches the flow with the power draw of the connected device. An active PoE injector eliminates the risk of damaging the device and is the most common type used in industrial environments.

Active PoE injectors follow the IEEE 802.3af/at/bt standards; however, passive PoE injectors do not. Passive PoE injectors don’t perform a handshake sequence with the connected device. They are commonly referred to as “Always On” injectors because they send constant power through the Ethernet cable to the device it is connected to. Passive PoE injectors are riskier, having the potential to supply more power than the device requires. Therefore, you need to ensure that the power the PoE device needs and the power supplied by the injector is exact.

Contact Us to Learn More About PoE Injectors

To understand more about the benefits a PoE injector brings to your next project, or if you’d like to discuss your networking equipment needs with a specialist, please contact us today.