I have the same problem.. So i instold antminer s7. i used apw3-12-1600w(PSU). I connecting my miner directly to a router via class 5, I use Ip Reporter to get an ip number. I made sure that the ethernet cord is firmly attached and connected 1600W PSU(s) to the miner. Sorry for my English and thanks anyway!
So is unit powering on? We need to know if this is power problem or ethernet problem. What voltage are you plugging that PSU into?
If it is on what is your normal IP range for your network? This could be a problem if using a different subset of IP's then it's static.