Passive Power over Ethernet (PoE) adapter allows to power LAN devices through typical 4-pair twisted-pair cable (eg UTP).
This solution enables Access Point powering, which is placed in hermetic box just by the antenna (to lower the loss in the RF cable), via twisted-pair cable from power source located inside a building.
The devices without the possibility to powering through the Ethernet port, should be connected as was shown at diagram No. 2.