An electric-field meter provided with a housing, an electrode assembly, a
shield assembly, a movement assembly, a position detection assembly, a
charge measurement circuit, and a leakage current compensation circuit.
The electric-field meter can be characterized as a field mill, an
induction voltmeter, an electrostatic fluxmeter or an agrimeter. The
electrode assembly is selectively exposed to the electric field. The
shield assembly alternately covers and exposes the electrode assembly to
the electric field. The movement assembly has a source of motive force
and a linkage operably connected to one of the shield assembly and the
electrode assembly for alternately covering and exposing the electrode
assembly to the electric field. The charge measurement circuit receives
charge on the electrode assembly. The charge measurement circuit provides
a charge detection signal indicative of the charge induced on the
electrode assembly as the electrode assembly is selectively exposed to
the electric field. A current compensation circuit is provided for
offsetting an average leakage current at the input of the charge
measurement circuit.