Current measuring shunt with circuitry mounted thereon

• US 6,646,430 B1
• Filed: 12/27/2000
• Issued: 11/11/2003
• Est. Priority Date: 06/30/1998
• Status: Expired due to Fees

• Current Assignee: Eaton Electric Ltd (Eaton Corporation PLC.)
• Original Assignee: Delta Electrical Limited (Valmont Industries Incorporated)
• Inventors: Reeder, Brian Martin, Crosier, Mark David, Murray, Martin Anthony, Skerritt, Robert Charles
• Primary Examiner(s): Oda, Christine K.
• Assistant Examiner(s): Hamdan, Wasseem H.
• Application Number:
  US09/720,683
• Time in Patent Office: 1,049 Days
• Field of Search: 324/421, 324/424, 324/127, 324/142, 324/128, 324/117.H, 324/126, 324/99.D, 361/87, 361/85, 361/42, 361/44, 361/45, 327/513, 327/262, 702/60, 341/155, 338/49
• US Class Current: 324/126
• CPC Class Codes: G01R 1/203 Resistors used for electric measuring, e.g. decade resistors standards, resistors for comparators, series resistors, shunts resistors in general H01C; microwave or radiowave terminations H01P1/26; coupling devices H01R
• CPC Class Codes: G01R 1/30 Structural combination of electric measuring instruments with basic electronic circuits, e.g. with amplifier
• CPC Class Codes: G01R 19/2506 Arrangements for conditioning or analysing measured signals, e.g. for indicating peak values G01R19/003 takes precedence; Details concerning sampling, digitizing or waveform capturing displaying waveforms G01R13/00; analog sampling G01R19/0053

Abstract

A current sensor which has a rigid metallic link member having two end portions of conductive material and an intermediate portion of resistive material interconnecting the end portions. An integrated circuit analog to digital converter is mounted on the link member. The converter has analog input terminals for connection to respective ones of the two end portions of the link member and digital output terminals for connection to a processing apparatus.

Claims

1. A current sensor comprising a rigid metallic link member having two end portions of conductive material and an intermediate portion interconnecting the end portions, said intermediate portion being formed of a resistive material, and an integrated circuit analog to digital converter mounted on said link member, said converter having analog input terminals connected to respective ones of said two end portions and digital output terminals for connection to a processing apparatus.

2. A current sensor as claimed in claim 1 in which the converter is attached to the link member by means of a layer of electrically insulating adhesive.

3. A current sensor as claimed in claim 2 in which the converter is attached to the intermediate portion.

4. A current sensor as claimed in claim 3 in which the analog input terminals of the converter are connected to the end portions by means of wire bonds.

5. A current sensor as claimed in claim 1 in which the converter has a voltage reference terminal for connection to a reference voltage source and said converter operates to provide digital output signals representing the current through said intermediate portion and digital output signals representing the voltage on one of the end portions.

6. A current sensor as claimed in claim 1 in which said converter includes a delta-sigma modulator which provides a high frequency one-bit digital data stream.

7. A current sensor as claimed in claim 6 in which the converter also includes at least one decimation filter stage.

8. A current measurement apparatus including at least one current sensor as claimed in claim 1 and a processor circuit connected to receive and process digital signals received from said current sensor.

9. A current measurement apparatus as claimed in claim 8 in which the processor circuit is configured to carry out one or more decimation filtering operations on the received digital signals.