Power over Ethernet 4 of the 5 Auto-Negotiation RJ45 ports (Port 1 to Port 4) of the switch support Power over Ethernet (PoE) function. These PoE ports can automatically detect and supply power with those IEEE 802.3af compliant Powered Devices (PDs). Overload Arrangement TL-SF1005P has the priority function which will help protect the system when the system power is overloaded. If all PoE PDs power consumption is >= 58W, a priority will be arranged among the PoE ports, then the system will cut off the power of the lowest-priority port. Port Priority Function Priority (port-1=port-2=port-3>port-4): This function will help to ensure the normal operation of the system, it means Port 4 will be cut off when all total PoE PDs power consumption exceed 58W. For an example, Port 1, 2 and 4 is using 15.4W (maximum power for per port is 15.4W); the system power is 46.2W in total. If there is an additional PD inserted to Port 3 with 12W, and then the system will cut off the power of Port 4 because of the overloaded power, this means Port 1, 2 will use 15.4W, and Port3 will use 12W, no power will be supplied to Port 4.