Fluke 931B

This True RMS Differential Voltmeter is designed for rapid measurements of AC waveforms regardless of their shape.

Accuracies to 0.05% of reading are obtained in a simple to operate portable instrument with a five digit readout and automatic indicating decimal point.

The instrument employs the principle of the differential thermocouple transfer standard to obtain its high degree of accuracy.

It incorporates unique solid-state circuitry to accomplish the transfer automatically and almost instantly as the voltage readout dials are adjusted to their proper setting.