A PoE injector plays more of a supporting or supplementary role. It provides power in a non-PoE network. Such networks may have a regular Ethernet switch without the PoE feature. The injector and the non-PoE switch are connected to an Ethernet cable and powered on. Overall, with injector, you can connect various other smart devices, such as phone, IP camera, and so on, onto the network. A PoE injector primarily enables you to connect a PoE-enabled device to a non-PoE port. This way, PoE-enabled device can transfer electric energy as well as receive data over the network.