A system and method for enabling power applications over a single communication wire pair. In one embodiment, a data transformer is provided that has three separate windings. Two of the windings are tied to each other via high frequency pass DC-blocking capacitors, or another suitable element that creates an AC path while providing a DC block, such that the voltage forms on either ends of the DC-blocking capacitors and the signal is sent on the outer legs of each winding. A circuit measures the current draw (I) and injects a current proportional to, but smaller than, I into a third bias cancellation winding.