Electrostatic Fluxmeter

an instrument for measuring the strength of an electrostatic field. The operation of an electrostatic fluxmeter is based on the relationship between the surface density σ of the charge induced on a conductor by an electric field and the electric field strength E; that is, E = 4πσ.

A distinction is made between static electrostatic fluxmeters, in which an electrometer is used to measure the charge magnitude induced on a well-insulated measuring electrode (usually a flat plate) by the field being measured, and dynamic electrostatic fluxmeters, in which the field strength at the measuring electrode varies constantly as a result of the movement of an additional electrode. Current or the potential variations created in dynamic fluxmeters serve as a measure of the field strength being measured. Electrostatic fluxmeters can be used to measure field strengths that range from 10^–1–1 volt/m to 10⁶–10⁷ kilovolts/m at frequencies from 0 hertz (Hz) to 1000 Hz.

Electrostatic fluxmeters are widely used in geophysics and engineering, especially for the measurement of rapidly changing quantities on moving objects such as aircraft and rockets and in media that have low conductivity or, as in clouds, a high moisture content.