Shown here is the solution for all applications where GR1089 inter-building compliance must be achieved. The SEP Ethernet Protector has full GR1089 compliance. One decision that must be made is based on the PoE question. If power is or might be present, it is recommended that a 72V SEP device be used. If the application is sure to be free of power, the 8V SEP will provide superior protection. Note that pins 3 and 6 of the SEP device are shown grounded. To be strictly compliant to the IEEE802.AT spec, pins 3 and 6 should be left unconnected.  However, if the PoE supply is ground referenced, then grounding pins 3 and 6 is a good idea. Once again, two TeleLink® fuses are needed to maintain good line balance and to comply with GR1089. If the 8V SEP device is used, the bias supply should be 5V. If the 72V SEP device is chosen, the PoE supply should be used.