I have a hEX POE that I am attempting to power a Doorbird IP camera with. The hEX POE operates in POE mode B but the Doorbird (https://www.doorbird.com/poe) only supports Mode A and only uses 2 wire pairs to connect. Can I just create a crossover cable to power the device or will I need to get a separate injector?

Thanks.

In theory you could create that but you'd need some electronics as data and power need to be mixed, are there B to A converters? I don't know of any, you'd better do with an good A injector as I believe reliability is important for a door camera.

If I understand the Mode B standard, pins 4 5 and 7 8 carry power. If I connect wires 4 and 5 to the positive terminal and 7 and 8 to the negative terminal on the device would that supply it with 48v DC?