Do I have a bad unit or are the POE standards too complicated for my tiny brain?

I bought an edgerouter X and a UAP-AC-Pro-US.

The UAP-AC-Pro came with a 48V POE injector.  Which I thought should allow me to power both the edgerouter X and the UAP-AC-Pro.  When I plug in the POE injector to the edgerouter X eth0 the light on the POE injector flashes on and off in the universal "something broke" signal.

The problem is that I think this work.  So is it:

1) I have faulty hardware? 

  1.1) is the POE injector?

  1.2) is the edgerouterX?

2) the POE for edgrouter X and UAP-AC-Pro are not compatible?

If #2 then please point me to the documentation that explains why?

thanks!