Not sure if you want to use the Doorbird supplied psu and WiFi connection, use the all in one POE method.

Get the POE injector that works. We have tested and use these POE injectors ourselves, so we can guarantee they work.

IEEE 802.3af compliant, these little injectors will inject power over your Ethernet Cat 5e or 6 cable to not only connected your Doorbird unit to the network, but also supply power to them up to over 80 meters away.