Patent · US Expired

A.C. capacitance measuring bridge

US4059797A · kind A · utility

6Cited by
4References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 27, 1976
Grant dateNov 22, 1977
Priority date
Expiry dateDec 27, 1996

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R27/2605
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Alternating current capacitance measuring bridge for measuring the capacitance of capacitors having one electrode connected to an external earth. It comprises a first metal screen box connected to the common terminal of the secondary windings of a differential transformer and directly to screened coaxial connections of capacitors inside of which an alternating voltage source and the transformer are placed, and means for d.c. supplying the source via internal d.c. supply terminals comprising a first winding connecting to the common terminal of secondary windings and the external earth, a second and third windings connecting to the internal d.c. supply terminals and external d.c. supply terminals, the first, second and third windings having a high impedance at the operational frequency of the source, two capacitors of high impedance inserted between the internal d.c. supply terminals and said first screen box, and two other capacitors of high impedance inserted between the external d.c. supply terminals and the external earth. In addition, the measuring bridge comprises a second metal box screen containing all the elements of the measuring bridge and connected to the external earth. …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.