Every CCTV and WiFi install runs on PoE, and the switch is where under-speccing hurts. Devices that reboot at night, access points that negotiate down, a spare port that cannot actually power anything — all of them trace back to one line on the datasheet: the power budget. Here is how to read it, with the switch we would quote at each size.
The three PoE standards, in one minute
- 802.3af (PoE): up to 15.4 W per port — phones, fixed cameras, small access points.
- 802.3at (PoE+): up to 30 W — PTZ cameras, WiFi 6 access points, video intercoms.
- 802.3bt (PoE++): up to 60–90 W — WiFi 7 access points, pan-tilt heaters, small NVRs and displays.
A switch negotiates down, never up: an af-only switch will not run an at-class access point at full performance. Check the class of your most demanding device first, then choose the switch — not the other way round.
Power budget: the port count is not the promise
A “16-port PoE” switch with a 130 W budget cannot deliver 30 W on sixteen ports — that would need 480 W. Add up the real draw of everything you are connecting, add 20% headroom for cold starts and IR at night, and compare against the budget. For a 12-camera site of 6 W domes plus two 25 W PTZs, that is (12×6 + 2×25) × 1.2 ≈ 146 W — a 190–250 W class switch, not a 130 W one.
Managed or unmanaged?
For a flat network of cameras on their own switch, unmanaged is fine and saves real money. A managed switch earns its price when you need VLANs (separating CCTV from office traffic), per-port power cycling (rebooting a hung camera remotely instead of driving to site), or uplink monitoring. Most installers standardise on managed for anything above 8 ports — the remote power-cycle alone pays for the difference on the first callout it saves.
Grandstream GWN7700MP — the unmanaged pickFanless 5-port 2.5G desktop with 4 PoE ports — a couple of cameras or one AP.View product →
Grandstream GWN7721P — the managed pick10-port 2.5G PoE with VLANs and per-port power cycling from the cloud.View product →
Uplinks and distance
Gigabit uplinks congest quickly once a recorder, a backup job and remote viewing share them — prefer a switch with SFP/SFP+ uplinks for fibre or 10G links between cabinets. And remember PoE's 100 m limit per run: beyond that you need an extender or a mid-span injector.
Grandstream GWN7822P — the whole-site switch24 PoE++ ports and 4 × 10G SFP+ uplinks — cameras, APs and phones from one budget.View product →
Zyxel XGS2220-54FP — the campus core48 ports, 960 W and Layer 3 for camera-heavy, multi-cabinet estates.View product →
Where to start
Browse PoE switches across Grandstream, Zyxel, TP-Link and more, or see the full switch range. Unsure on the budget maths? Send us the device list — we will size the switch and the uplinks for you.