The system is intended to provide an isolated power supply for an electrical
load. It contains a generator for producing a supply signal, and a transmission
path having two separate branch elements. The first branch element is designed
for transmission of the supply signal (S1) in the forward direction, and
the second branch element is designed for transmission of the supply signal in
the backward direction, so that this results in a closed circuit for the supply
signal. The two branch elements contain means for isolation. The load can be supplied
by the supply signal with an electrical power of at most 100 mW.