This solution displayed here provides protection against possible power fault events by adding a fuse for each wire. These fuses will NOT cause nuisance openings as they are surge tolerant. This recommended solution adds a secondary protector in a differential mode ONLY (common mode protection on the line side violates IEEE 802.3 isolation requirements) on the line side followed by a tertiary protector (PHY) side. This tertiary protector must be connected to the Ethernet PHY ground reference point, NOT a line side ground reference. The specific selection of the overvoltage protector depends upon the Ethernet PHY reference voltage. Please note the VRWM column for more information.