An Instrument for Measurement of Very High Resistance
Frank J. Lynch, Clarence L. Wesenberg · Review of Scientific Instruments · 1954
An instrument for the accurate measurement of resistance in the range 109 to 1013 ohms is described. A constant current flows through the resistor under test, and the resulting potential drop is measured with an electrometer. The constant current is the displacement current flowing through a standard condenser when the potential difference across the condenser changes linearly with time. The potential drop across the resistor is measured by a recording dynamic-condenser electrometer. Provision is made for measuring resistance with potential drops from 3 mv to 10 volts across the resistor. The accuracy of the resistance measurement is dependent only upon wire-wound potential dividers, the dimensions of a parallel plate condenser, and the power-line frequency. The accuracy of the present instrument is about 0.5 percent. For this accuracy, the time of measurement is about 6R×10−11+10 seconds.