PoE Injector / Splitter / Extender

Firstly let me introduce the two types of PoE PSE devices:

1. Active/Standard PoE: Compliant with IEEE802.3af/at standard (af=15.4W, at=30W), support PD (Power Detection) function; only 48VDC power output;
   
2. Passive/Non-standard PoE: Provide power passively without standard, no PD functions, support 12/24/48VDC power output.
   This provides power over the Ethernet lines, but it doesn't negotiate the amount of power or the wires on which the power is sent. Many devices use Passive PoE (notably, the Ubiquiti line of network hardware often uses 24v Passive PoE) to provide power to remote devices. With Passive PoE, the proprietary nature of the power specifics means that it's often wise to use only power injectors or switches specifically designed for the devices that require Passive PoE. The power is "always on", so it's possible to burn out devices if they're not prepared for electrified Ethernet wires, or if the CAT5 cabling is wired incorrectly.

All in all, you need to check the video phones or IP cameras is Passive PoE devices or not?