A capacitive voltage sensor assembly includes a first electrode extending along a longitudinal axis, a tubular section surrounding a portion of the first electrode and positioned radially outward from the longitudinal axis and the first electrode, the tubular section including an insulating layer, an inner conductive layer, and an outer conductive layer, and a mass of dielectric insulating material at least partially enclosing the first electrode and the tubular section. The mass of dielectric insulating material fills through openings formed in the tubular section.

This surface potential sensor is provided with an electret electrode (28), which is configured of a metal film (26) and an electret film (27), said electret electrode being provided on an upper surface of a diaphragm (25) of a semiconductor substrate. Four piezoresistors (29a, 29b, 29c, 29d) are formed on the diaphragm (25), and a distortion quantity detecting unit (32) is configured by forming a bridge circuit using the piezoresistors. Since an electrostatic force that operates between an object and the electret electrode (28) changes corresponding to potential of the object, and the electret electrode (28) warps corresponding to the change, the potential of the object can be detected by measuring a distortion quantity of the electret electrode (28) by means of the distortion quantity detecting unit (32). Consequently, not only the potential of the object but also a polarity thereof can be detected with reduced size and high sensitivity.

A system for determining a shopping metric from static electricity comprises a plurality of static electricity sensors; a monitoring server that processes signals generated by the static electricity sensors and determines from the processed signals a store metric; and a static electricity measurement database that stores the store metric for subsequent retrieval for analysis.

A system for measuring electric characteristics of an earth formation includes a carrier configured to be disposed in an earth formation, and an inductive measurement assembly including an antenna configured to generate an oscillating magnetic field in the earth formation and measure a resistivity of the formation by detecting a signal in response to currents induced in the formation. The system also includes a capacitive measurement assembly including a capacitive measurement electrode configured to detect a signal in response to a measurement current injected into the formation, the capacitive measurement electrode disposed between the antenna and the formation and in a path of the magnetic field, the capacitive measurement electrode formed from a plurality of constituent electrodes that are electrically isolated from each other so as to prevent induction of eddy currents across the plurality of electrodes.

Propagating brush discharge testing systems may include a dielectric layer, an initiation electrode, a high-voltage switch, an optical sensor, and a controller. The initiation electrode has an exposed tip positioned adjacent to a surface of the dielectric layer. The high-voltage switch is configured to selectively isolate the initiation electrode from ground potential. The optical sensor is positioned and configured to sense light generated at the surface due to a propagating brush discharge. The controller is programmed to operate the high-voltage switch to ground the initiation electrode and to operate the optical sensor to collect light from the propagating brush discharge. Propagating brush discharge testing methods include positioning an exposed tip of an initiation electrode with respect to a surface of a dielectric layer, then charging the surface, and then grounding the initiation electrode to neutralize charge on the surface (generally causing a propagating brush discharge).

A voltage sensor housing includes a top portion including a conductive top portion composed of conductive material and non-conductive top portions composed of non-conductive material, a bottom portion composed of non-conductive material, side portions composed of non-conductive material, wherein the top portion the bottom portion and the side portions define an interior area structured to hold a voltage sensor, and conductive side portions composed of conductive material and being disposed adjacent to the side portions. The conductive top portion is electrically floating and the conductive side portions are electrically grounded.

A capacitor has a variable capacitance settable by a bias voltage. A method for setting the bias voltage including the steps of: (a) injecting a constant current to bias the capacitor; (b) measuring the capacitor voltage at the end of a time interval; (c) calculating the capacitance value obtained at the end of the time interval; (d) comparing this value with a desired value; and (e) repeating steps (a) to (d) so as long as the calculated value is different from the set point value. When calculated value matches the set point value; the measured capacitor voltage is stored as a bias voltage to be applied to the capacitor for setting the variable capacitance.

A capacitor has a variable capacitance settable by a bias voltage. A method for setting the bias voltage including the steps of: (a) injecting a constant current to bias the capacitor; (b) measuring the capacitor voltage at the end of a time interval; (c) calculating the capacitance value obtained at the end of the time interval; (d) comparing this value with a desired value; and (e) repeating steps (a) to (d) so as long as the calculated value is different from the set point value. When calculated value matches the set point value; the measured capacitor voltage is stored as a bias voltage to be applied to the capacitor for setting the variable capacitance.

A capacitive sensor to sense an electric field has a shield tube that extends axially along its own axis and has a first open end, an electric field sensor positioned within the shield tube, a source electrode, and a mass of dielectric insulating material positioned within the shield tube and around the shield tube. The shield tube is formed by a jacket having a plurality of first through openings that each have an area comprised between a minimum of 0.1 mm.sup.2 and a maximum of 3 mm.sup.2.

A voltage sensor housing includes a top portion including a conductive top portion composed of conductive material and non-conductive top portions composed of non-conductive material, a bottom portion composed of non-conductive material, side portions composed of non-conductive material, wherein the top portion the bottom portion and the side portions define an interior area structured to hold a voltage sensor, and conductive side portions composed of conductive material and being disposed adjacent to the side portions. The conductive top portion is electrically floating and the conductive side portions are electrically grounded.