A downhole measurement tool circuit and method to balance fault current in a protective inductor, which keeps an alternating current balanced in a protective choke during a phase-to-ground fault condition in a power cable or a downhole motor of an electrical submersible pump. The downhole measurement tool circuit and method cause a conducting of current during the negative polarity voltage portions of a phase-to-ground fault condition, but do not cause a conduction of negative polarity voltage during use of a negative polarity megger.