Brandon
Well-Known Member
It's relatively simple to DIY power over 10/100 links using the spare 4+5, 7+8 pairs, but not so much with gigabit ethernet that needs all 4 pairs for data. To have both power and data, a transformer is required, such as (link).
Looking for a simpler way, by using 2 Mikrotik gigabit passive POE injectors, discovered they can also be used as de-couplers!
Below is a demo powering 2 devices from 1 power supply:
PSU 24v 800ma -> POE injector A <----ethernet cable----> POE injector B -> 2x DC/DC stepdowns -> 12v & 5v outputs
For the 12v load: a non-poe gigabit switch, for the 5v load: an ip phone.
A multimeter on the supply end measures the total load (290ma).
Also connected to the switch: another switch, router & pc (not in pic).
The switch link led's: green = 10/100, orange = 1 gigabit.
Looking for a simpler way, by using 2 Mikrotik gigabit passive POE injectors, discovered they can also be used as de-couplers!
Below is a demo powering 2 devices from 1 power supply:
PSU 24v 800ma -> POE injector A <----ethernet cable----> POE injector B -> 2x DC/DC stepdowns -> 12v & 5v outputs
For the 12v load: a non-poe gigabit switch, for the 5v load: an ip phone.
A multimeter on the supply end measures the total load (290ma).
Also connected to the switch: another switch, router & pc (not in pic).
The switch link led's: green = 10/100, orange = 1 gigabit.
