PoE Budget Planning for IP Camera Deployments
PoE power planning is one of the most common hidden failure points in commercial surveillance deployments. On paper, everything looks fine: the switch has enough ports, cameras are PoE-capable, and video is online. Then night falls, IR turns on, heaters kick in, and a few cameras start resetting or dropping intermittently. It looks like firmware, cabling, or a bad camera batch. In reality, the system is underpowered at peak load.
Why PoE planning fails in the real world
Most PoE sizing mistakes come from designing to typical draw instead of peak draw. Cameras have multiple operating modes and peripherals that change power demand:
- IR illumination increases draw at night.
- Heaters and blowers increase draw in cold environments.
- PTRZ motors and autofocus spike during adjustment.
- Higher-end analytics models often have higher peak draw.
- Switches have both per-port limits and total chassis limits, and both matter.
When you size PoE too tightly, you do not always get a clean failure. You get intermittent resets, partial IR behavior, or random disconnects that are painful to diagnose. The fix is simple: design with the right math and explicit headroom.
The sizing method that holds up at scale
Step 1: Use maximum wattage, not typical wattage
Start with the manufacturer maximum power spec per camera whenever available. If you only have a typical number, treat it as a warning sign and size conservatively. Peak draw is what breaks deployments, especially overnight.
Step 2: Calculate total peak draw by camera group
Step 3: Add headroom and size the switch budget
PoE planning is one piece of a deployment-ready architecture
Power planning should be tied to retention, storage, and recording platform selection so you do not solve one bottleneck while creating another. These guides connect directly:
- Retention Modeling and Storage Planning
- Video Recording Platforms Guide
- VMS Selection and Architecture