Patent ID: 6984971

Claim:
An electric-field meter for measuring at least one of a magnitude and polarity of an electric field, comprising: a housing at least partially constructed of a conductive material, the housing defining a retaining space; an electrode assembly on the housing and selectively exposed to the electric field; a shield assembly for alternately covering and exposing the electrode assembly to the electric field; a movement assembly having a source of motive force and a conductive linkage operably and electrically connected to one of the shield assembly and the electrode assembly, the source of motive force moving the conductive linkage to move one of the shield assembly and the electrode assembly in alternating, opposed directions to alternately cover and expose the electrode assembly to the electric field; a charge measurement circuit receiving charge on the electrode assembly, the charge measurement circuit providing a charge detection signal indicative of the charge induced on the electrode assembly as the electrode assembly is selectively exposed to the electric field; and a flexible conductor mechanically and electrically connected to the conductive linkage of the movement assembly to move with the conductive linkage and also electrically connected to one of a reference potential and the charge measurement circuit wherein the conductive linkage, the shield assembly and the source of motive force are maintained at the reference potential when the conductive linkage is connected to the shield assembly, and wherein the conductive linkage and the electrode assembly are electrically connected to the charge measurement circuit when the conductive linkage is connected to the electrode assembly.