fieldscouter7

I have a 16 channel/port swann system. I've got a few cameras up and running, they are all just their own cat5 cables. Now I got a few more cameras to set up in our plant, but only have 1 line running back from there to the office. I got a POE box and want tried plugging a few cameras into it, and ran the one line back to the office. It worked while running just the one camera, but hooking up two, then it did not give me any video. Any one know where in my settings I need to change something to allow it to work? Or where did I go wrong? Thanks