DIFFERENTIAL CURRENT SENSOR

摘要

The invention relates to a differential current sensor for measuring a differential current (ΔI) between an electric current (IH) through a delivery conductor (H) and an electric current (IR) through a return conductor (R), with two low-ohmic current-measuring resistors (RH, RL) for measuring the currents (IH, IR) in the delivery conductor (H) and return conductor (R) and two measuring devices (MEH, MEL) with a measuring transducer for measuring the voltage drops (UH, UL) over the two current-sense resistors (RH, RL) in each case, and also with two voltage references (UREFH, UREFL) for calibrating the measuring devices (MEH, MEL). It is suggested that the two measuring transducers successively measure both the voltage drop (UH) over the respective current-sense resistor (RH) and the associated voltage reference (UREFH, UREFL).

主权项

1. A differential current sensor adapted for measuring a differential current between a first electric current through a delivery conductor and a second electric current through a return conductor, in particular for a direct-current power supply system, comprising:
a) a low-ohmic first current-sense resistor for measuring the first electric current through the delivery conductor, wherein the first current-sense resistor is arranged in the delivery conductor and the first electric current flows through the first current-sense resistor, b) a first measuring device with a first measuring transducer for measuring a first voltage drop over the first current-sense resistor, c) a first voltage reference for calibrating the first measuring device, d) a low-ohmic second current-sense resistor for measuring the second electric current through the return conductor, wherein the second current-sense resistor is arranged in the return conductor and the second electric current flows through the second current-sense resistors, e) a second measuring device with a second measuring transducer for measuring a second voltage drop over the second current-sense resistor, f) a second voltage reference for calibrating the second measuring device, wherein g) the first measuring transducer successively measures both the first voltage drop and the first voltage reference, and h) the second measuring transducer successively measures both the second voltage drop over the second current current-sense resistor and the second voltage reference.