Abstract: Improved circuitry for connecting a generator to a battery with a very low voltage drop conductive path whenever the generator is capable of charging the battery, yet preventing reverse current flow when the generator is not capable of charging the battery. Mechanical contacts are employed to maintain a low voltage drop connection and are controlled to open and close by known techniques. In the preferred embodiment, sensing when the generator is no longer generating sufficiently to substantially charge the battery is accomplished by monitoring the polarity of the tiny voltage drop across the closed mechanical contacts. With the mechanical contacts open, sensing when the generator begins generating sufficiently to charge the battery is accomplished by monitoring the forward voltage drop across a blocking diode in series between the generator and battery. The mechanical contacts are in parallel with the diode, so the diode voltage drop is eliminated when the mechanical contacts are closed.