this post was submitted on 06 Oct 2025
        
      
      14 points (100.0% liked)
      networking
    3243 readers
  
      
      1 users here now
      Community for discussing enterprise networks and the ensuing chaos that comes after inheriting or building one.
        founded 2 years ago
      
      MODERATORS
      
    you are viewing a single comment's thread
view the rest of the comments
    view the rest of the comments


Pump the brakes. You need to find out what voltage it wants over PoE. There is NO guarantee that it is the same as the 12v input.
Standard Poe is like 48v. Unifi used 12v and 24v Poe for a while to power their antennas and AP’s but this is not standard and they have stopped doing it. This was supplied by their special poe injectors.
You will cause serious damage if you supply the wrong voltage to your device.
Edit: reread your post. The negotiation protocol is to
a. See if the device plugged into a Poe switch actually needs power
B. Negotiate higher supply’s like poe +, ++ and in future +++.
For a Simple PoE device the negotiation is not needed.