PoE Technology: One Cable for Power and Video
What PoE is, why it simplifies IP camera installation and how to choose the right switch.
PoE (Power over Ethernet) delivers both power and data to an IP camera over a single network cable — no separate electrical wiring needed at each camera.
How it works
A PoE switch or injector supplies 48V over UTP cable (Cat5e/Cat6). Standard PoE (802.3af) provides 15.4W, PoE+ (802.3at) — 30W, enough for the vast majority of cameras including PTZ.
Choosing a switch
The key parameter is the PoE budget — total power the switch can deliver. 8 cameras need roughly 60-100W, so an 8-port switch should have at least a 120W budget. Extend mode matters too — some switches support up to 250m instead of the standard 100m.
Practical tip
An NVR with built-in PoE ports (e.g. Dahua NVR4108HS-8P) is the best choice for small sites: cameras plug straight into the recorder and no separate switch is needed.
