What Is a PoE Switch and What Can It Power?
A PoE switch is a network switch that sends power down the same Ethernet cable that carries data. Plug a camera or access point in, and it turns on. No outlet, no power adapter, no extension cord.
That sounds like a small convenience. In practice it changes where you can put devices, how clean the install looks, and what happens when the power goes out.
What PoE Actually Does
PoE stands for Power over Ethernet. A standard switch moves data between devices. A PoE switch does that too, but it also supplies low-voltage DC power to any compatible device on the other end of the cable.
The device negotiates with the switch when you plug it in. The switch checks what the device needs, sends only that much power, and skips ports with non-PoE gear like a laptop, so nothing gets damaged.
The practical result is that you can mount a camera at the peak of a garage or an access point in the middle of a ceiling with just one cable to the device. If you want a deeper look at the camera side, see our post on PoE security cameras and why they beat WiFi cameras.
What a PoE Switch Can Power
The list is longer than most people expect. Security cameras are the classic use, but they're far from the only one. WiFi access points, VoIP desk phones, door entry and access control readers, and some small displays and intercoms all run on PoE.
Which one you can run depends on the power standard the switch supports. Here's the short version.
Match the switch to the hungriest device you plan to run, then leave headroom. A PTZ camera with heaters or a high-end access point can draw far more than a basic fixed camera.
The Power Budget Matters More Than Port Count
Every PoE switch has a total power budget, the combined wattage it can deliver across all ports at once. An eight-port switch does not mean eight ports at full power. A switch with a modest budget can power four cameras happily and choke when you add a fifth device.
This is the spec people overlook and installers check first. Add up what every device needs, add a margin, and pick the switch that clears it. Under sizing means random reboots and flickering cameras, and those problems are maddening to trace.
Cable matters too. Runs top out around 100 meters, and cheap or damaged cable loses power along the way. Solid copper Cat6 is the safe bet, and our guide to Cat5e vs. Cat6 vs. Cat6A explains why.
Do You Need One?
If you're installing wired security cameras, yes. If you're adding ceiling-mounted WiFi access points to fix dead zones, almost certainly. Our comparison of access points vs. mesh systems covers why a wired access point beats a mesh extender nearly every time.
If all you have is a laptop, a printer, and a streaming stick, a regular switch is fine. You only pay for PoE when you have something to power with it.
Plan for growth here, a switch with a few spare PoE ports costs little at install time and saves a second visit later. We design networks around what you'll add in a year, not just what you own today.
We install PoE switches, cabling, and network closets for homes and businesses across Bolingbrook, Naperville, Woodridge, Romeoville, Downers Grove, and Plainfield. See our networking and cabling services or our security camera systems. No contracts, no monthly fees.
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