Current-measuring device, especially for determining the motor current of a direct-current motor

US4851763A · kind A · utility

Assignee

• Heidelberger Druckmaschinen AG · DE

Inventors

• Bertold Grutzmacher · Schriesheim, DE
• Helmut Meyer · Hilden, DE

Key dates

• Filing date: Mar 21, 1988
• Grant date: Jul 25, 1989
• Expiry date: Mar 21, 2008

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R17/00
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Current-measuring device including a non-contacting current sensor and an evaluating device connected downstream to the sensor for producing an output signal proportional to a current being measured, comprising a circuit arrangement for determining a zero drift of at least one of the evaluating device and the current sensor from symmetrical components of the current being measured and for correcting the drift.