Precision integrator for D-C potentials

Integrators of small direct currents and potentials have been put to good use in a wide variety of applications, such as in measuring photographic exposure by-time-integrating the output of a photovoltaic cell, in registering watt-hours derived from the d-c millivolt (mv) output of thermal watt converters and electronic watt converters, and in tallying the amount of gold consumed in gold-plating operations by integrating the potential drop in the plating current shunt.