Let’s see how it works, what you need to pay attention to, and how you can build your own system easily, affordably, and without mistakes.

How does PoE work in simple terms?

Normally, a network device needs two cables: one to get internet (the classic UTP network cable) and one to plug into the power outlet.

With PoE, we eliminate the power cable. We use only the internet cable, which also carries the voltage the device needs to turn on and operate.

To achieve this, you need 3 things:

1. A device that supports PoE (e.g. an IP camera or an Access Point).

2. A simple network cable.

3. A source that "feeds" the cable with power (usually a PoE Switch or a PoE Injector

Which PoE standard do I need? 

When you’re looking at devices on the market, you’ll see some strange codes next to the word PoE. Don’t worry, these are just the “categories” based on how much power (Watt) a device can provide or receive:

• Standard PoE (802.3af) – Up to 15.4W: Ideal for simple, fixed indoor cameras and older IP phones.

• PoE+ (802.3at) – Up to 30W: You need it for most outdoor cameras and for the classic Access Points that give us Wi-Fi at home.

• PoE++ (802.3bt) – From 60W to 90W: The most modern and powerful one! It is absolutely essential if you want to connect the new, highly powerful Wi-Fi 7 Access Points or large outdoor cameras that rotate all around (PTZ) and have powerful spotlights for the night.

⚠️ Big Warning: Make sure you are buying Active PoE equipment. Active PoE is smart: it “talks” to your device and only supplies power if it asks for it. Stay away from Passive PoE, because it sends power blindly. If you accidentally connect your laptop or computer there, you could burn them out!

The trap with the Switch’s “Wallet”

This is the number 1 mistake most beginners make. Let’s assume you buy a 4-port PoE Switch to connect 4 cameras that say they need 15W each (4 x 15 = 60W total).

Before you buy it, you need to check the Switch’s specifications for the Total PoE Budget (the total power reserve). If the Switch says it has a PoE Budget of 40W, then it will not be able to handle all 4 cameras at once, even though it has 4 ports! As soon as it gets dark and the cameras’ infrared lights turn on, the Switch will “crash” and the cameras will turn off.

Always choose a Switch whose total Budget is greater than the Wattage of all our devices combined.

Which UTP cable should I choose?

Since the network cable will now also carry electrical current, not all cables are suitable for this job. Pay attention to the following two:

• Choose Cat6 or Cat6a category: These are thicker cables, can handle more current, have better shielding, and do not heat up.

• Stay away from CCA (Copper Clad Aluminum) cables: In the market there are very cheap cables that have aluminum inside and a thin copper coating on the outside. Do not buy them! Aluminum struggles to carry current, the cable will overheat dangerously, and your devices will keep restarting. Always ask for cables made of 100% pure copper (Pure Copper or Solid Copper)

Small tips for saving money and covering long distances

• Do you want to connect only ONE device? If you already have a good router and want to install just one camera, don’t buy an entire Switch. Buy a PoE Injector. It is a small, inexpensive accessory that plugs into the wall, takes the regular internet from your router, and outputs a cable that carries both internet and power for your camera.

• Is the camera very far away (over 100 meters)? Normally, at 100 meters the signal weakens and the power is lost. If you want to go farther (e.g. to the edge of the property), look for a PoE Switch with Extend or Long Range mode. With the press of a button, the Switch slightly reduces internet speed (which makes no difference for a camera) but sends power and data up to 250 meters!

Summary: What to check before you buy

• The camera or Access Point clearly states that it supports PoE.

• You checked how many Watt your device requires so you can choose the right standard (PoE, PoE+ or PoE++).

• The Switch you chose has enough Total PoE Budget to power them all at once.

• You bought Cat6 cables made of 100% pure copper (Pure Copper).

• Your equipment is Active PoE so you can have peace of mind.