1. What is Power over Ethernet?

Power over Ethernet (PoE) is a technology that allows you to power certain devices, such as IP phones, over network cables rather than traditional AC power outlets. This reduces the need for multiple cables, allowing for a less cluttered, simpler set up, whilst also providing greater flexibility for organising your office space.

Many IP phones now come with ‘PoE’ support – or Power over Ethernet – but what does this actually mean for you? Below, we’ve tried to clearly and simply explain some of the main benefits and features of PoE, to help you become fully informed before you make your purchase.

2.Why should I use PoE instead of traditional outlets?

PoE, as well as reducing clutter by eliminating the need for extra power cables, has other benefits. It lowers the cost of installation, as a qualified electrician is not required to install network cables, unlike with AC outlets. On top of this, PoE can be plugged into an Uninterruptible Power Supply (UPS). Unlike a mains outlet, a UPS will allow the devices to function for a short period in the case of a power cut.

3.Do I need new equipment?

Whilst it is certainly easier to use a PoE switch to power PoE-compliant devices, it is possible to upgrade your current equipment using a device called a PoE injector. A PoE injector, running off a separate power supply, connects to your existing network switch. It then injects power into your Ethernet cables, providing Power over Ethernet functionality.

These two devices both allow for great scalability, as they can be purchased at the size and complexity that suits your individual needs. You can get both large rack-mounted units and single-port devices for individual phones or conference units.

4. Does it require special cables?

PoE is able to work over any network cable that is Cat3 (category 3). The more recent PoE+ standard requires Cat5 (category 5) or newer in order to function.

5.What is PoE+?

PoE+ is a newer specification, which allows for a greater level of power to pass through the network cable, enabling it to power more complex devices. The specification is backwards-compatible, meaning it can function with the older PoE standard without any compatibility issues.

6. Key terms to know

UPS – Uninterruptible Power Supply
An uninterruptible power supply is an appliance that can provide short-term emergency power to a device in the case of a power cut. It works instantaneously, allowing the user time to either save or shut down what they are working on. It can also provide a large enough window for an auxiliary power source to begin working.

PoE Switch
This is a network switch with Power over Ethernet functionality included. It allows network cables to run directly from the switch to the PoE device.

PoE Injector
An appliance, connected to a power supply, which connects to a standard network switch. It injects electrical power into your network cables.