Over a long Ethernet cable run, your video signal will begin to weaken causing the quality of your video to degrade. This usually occurs at around 100m from the switch or hub. However, when you install a PoE extender, you're able to lengthen that cable run by another 100m. You can install multiple PoE extenders on a single cable run, but there is an upper limit to how long your cable run can be depending on the camera power and PoE switch. If you have any questions, give us a call at 800-997-8460 to speak with one of our experts.