Description: The chart of passive measuring device of current of loss is offered on earth of electrical equipment. The calculations of number of coils of the second puttee of differential transformer of current are resulted. The conducted researches of sensor of differential current allow to specify a formula for the calculation of optimum number of coils of the second puttee of differential transformer of current. On the chart of the electronic module of device, on the entrance of which a signal is given by power about 199 мкВт, supposed filing of an application on a patent.
Keywords: electrical equipment, grounding, Neutral, transformer, passive measuring device of current