The 2N¨ 9159014 2Wire converter set ie. 1 pair, allows you to use the existing wiring (2 wires) from your original door bell or door intercom to connect any TCP/IP device. You don•t have to configure anything, and you just need one 2N¨ 2Wire unit at each end of the pair and a power source connected to at least one of these units. The 2N¨ 2Wire unit then provides PoE power not only to the second converter, but also to all other connected IP end devices.
2N 2Wire Analog to IP Conversion Kit