What is a PoE Home Security Camera and How Does It Work?

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You may have heard the term PoE applied to home security cameras, and you may not know what that means. 

To put it simply, Power over Ethernet (POE) is a technology that lets the cables (ethernet) used to carry internet information, also carry electrical power.

That way, one cable does the job of two.  Unless you are using solar power, batteries, or another kind of wireless connection, you will need electrical power through a cable.  

What is Power over Ethernet (PoE)?

The “P” in PoE refers to the power.  

In discussing PoE cameras, let’s imagine there’s a physical power source involved here, because in fact there will have to be one somewhere for the camera to get its power.

The above image shows a basic security camera setup, and you can see there’s a power source coming from a regular outlet, which eventually makes its way to the camera.

As we said, when it comes to PoE, the ethernet cable is key, because it is transferring the power to the camera instead of two separate cables doing it (one ethernet, one power).

Cameras, whatever the type, need power to run, obviously.  Sometimes the power comes from an outlet on the wall, or it can come from batteries, which means no power cables are needed.  

Cameras with no cables or wires are, you guessed it – wireless cameras.

Now, a PoE camera is a wired camera, because the power source is not batteries, and it’s not solar-powered.

Rather, the power given to a PoE camera comes from an ethernet cable, as we said.

With a PoE security camera, the ethernet cable supplies the power to the camera, while sending network data (ie. footage) back from the camera to the network device you are using to obtain your internet connection.

Bundled within every ethernet cable are wires that are able to send power to a device, such as a security camera, among other things.

As we’ve already said, the “E” in PoE, stands for “Ethernet”.

An ethernet cable looks a little thicker than a regular computer or tv cable.

Ethernet cable

It could be any color of cable and the end is a plastic square.  This cable is a bigger “information highway” and carries pictures, videos, and text to and from the internet. 

Your security camera communicates, either wirelessly, or through an ethernet cable, with your network.  In the case of a PoE camera, it uses the ethernet cable.


Your security camera is set up either inside or outside.  It must weather resistant.  It gathers pictures, moving or still, and sounds.  

It then transfers the information with the PoE -Power over Ethernet cable, to your desktop computer, your laptop computer, your tablet, or maybe your “smart” phone.  

Note:  Usually an app is needed to “speak” with the camera, and most security cameras do come with their native app.  You might want to check into that before you purchase the security camera with the PoE technology.

Now, on to the word “over” in PoE, or Power over Ethernet.

The “O” in PoE, means that the power is running over, or through, an ethernet (internet) cable, in addition to the footage from the camera.  

So, think of this cable a a multi-lane highway, carrying power or volts of electricity, and pictures, videos, and words, to you, the consumer.

All this travels along the ethernet cable to a junction where there is a switch box and a router.  Think of the switch box and the router as two different buildings at the station.

The switch box manages the electrical power, and the information from the camera is routed out to your computer or phone.

Why use Power over Ethernet (PoE)

Savings –  If you used a regular electric volt power system, you would probably need to hire an electrician to install and hide the power cable from the camera to your outlet.

With the PoE system, no electrician is needed because the power cable is inside the ethernet cable.

You will still have to have this cable attached to your camera and your router which will probably be inside your house or place of business.  At least you won’t have to hire anyone to install it.

Flexibility – Since you are deciding where the ethernet PoE cable is going to be positioned, if you change your mind or decide to change to wireless, it is easy. (No fuss! No mess! Costs less money!)

Safety – The ethernet cables have been used for years to connect technology without issues.  The PoE system protects your network system from overloading, under powering, or incorrect installation.

Reliability – PoE power comes from a universal and compatible source i.e. security camera … and it is moving to similar devices on the other end such as routers and switch boxes.

Other devices can be added to this system if you wish, to control power surges and backups.

Scalability – The switch box and the routers that you would be connecting to, have multiple ports for more than one camera, which is great because you might need more than one security camera.

Also, these switch boxes and routers are built to handle the amount of data travelling from multiple cameras without any “traffic jams”.

Devices that use Power over Ethernet (PoE)

Here are 3 key areas where Power over Ethernet is used.

VoIP phones used the original PoE application.

These phones use a single connection to the wall socket.  They can be remotely powered off.  Even though this analog system is old technology, it still works.

IP cameras are very common with networked surveillance systems.  PoE is ubiquitous here.  The cameras can be repositioned easily and the information can be deployed quickly.

With the invention of wireless systems, Wifi and Bluetooth apps and RFID readers are PoE compatible, allowing remote locations, which are far from AC outlets, to have the option to use PoE if need be.

How to Upgrade to PoE

There is a device known as a PoE switch, which we mentioned earlier if you recall.  This is a network switch that has PoE built into it.

That allows other network devices to be plugged into the switch.  The switch will detect whether they are PoE compatible.

If so, things with work automatically.  The other nice thing about these switches is that there are low cost unmanaged edge switches with a few ports and more complex switches that handle sophisticated managements.

If that’s not enough, you might need a midspan (PoE injector). This device is used to add PoE capability to regular non-PoE network links.  Use the midspan to upgrade.  It is simple and the power injection is controlled and automatic.

Power devices such as IP cameras, can be upgrade to PoE, by using a PoE splitter.  This splitter will lower the voltage suitable for the camera by patching into the camera’s network connection.

The Power over Ethernet or PoE technology is still very effective and affordable. It is still compatible with newer power systems because of its adaptability.

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