 Can you run PoE over Cat5? Yes, Cat5e is capable of running PoE over its cable. Thus the power and the signal are transferred over the same cable. However, as devices that are powered by PoE are requiring a greater power supply thus the amount of power is required to be sent via data cabling. Thus as power increases the possibility of noise interference increases. Therefore with modern PoE systems, Cat6a is used more and more due to its shielded and better noise to signal protection.