The TP-SW8-D Power Over Ethernet (POE) 10/100Mb switch offered by Tycon Power Systems is a fully automatic high speed 8 port Ethernet switch with up to 35 Watts of POE power per port. It is a 48V 802.3af compatible switch. The unit supplies POE power to the remote device on the unused Ethernet pins 4,5(V+) and 7,8(V-).The Ethernet spec supports distances up to 100m (328 feet) between the POE switch and the remote device. The switch accepts DC power from a user supplied 46V-57V DC power source. There are 2 power inputs for attachment of primary and secondary power sources .