Using PoE Injectors

I have a brain cramp. All my PoE ports are in use but I need 1 more port for an IP Camera. I use a NonPoE port with a Injector to push power through the cable to power my camera.

"How does the Injector get it's power"

Plug the PoE injector into its own power outlet.

A PoE injector is primarily useful for the situation you describe.

You can install it anywhere a plug is located for power. In most cases this is near the switch, but it can also be near the camera or somewhere in between if needed.