The TP-DCDC-1224-HP offered by Tycon Power is a low cost and high reliability solution for those requiring 24VDC Power over Ethernet voltage from a 12V battery system. They have an integrated PoE injector. Passive PoE and 802.3at models are available. They have two inputs for connecting 2 power sources, such as a primary with a backup power source.
They accept data-in to a shielded RJ45 Jack and provide data-out and PoE power on the shielded RJ45 output jack. They work by supplying power on the unused Ethernet pins 4,5(V+) and 7,8(V-). They have various protections for surge, short circuit and overload. The units have a power output of up to 35W. The input and output are isolated so the units can accept minus voltage on input and can be wired for positive voltage on the output for those systems which are negative voltage based.
If the remote device does not support power over Ethernet, a (POE-SPLT-S) splitter is available to split the data and DC voltage at the remote device. If the remote device requires reverse voltage the POE-XOVER-S cable can be used.