Data acquisition system for a circuit breaker

• US 20020181174A1
• Filed: 06/27/2002
• Published: 12/05/2002
• Est. Priority Date: 11/05/1999
• Status: Active Grant

• Current Assignee: Siemens Industry Incorporated (Siemens AG)
• Original Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Inventors: Staley, Peter Spenlove, Bilac, Mario
• Granted Patent: US 6,661,632 B2
• Time in Patent Office: Days
• US Class Current: 361/18
• CPC Class Codes: H02H 1/0092 concerning the data processing means, e.g. expert systems, neural networks
• CPC Class Codes: H02H 3/006 Calibration or setting of parameters

Abstract

A circuit breaker system 10 (FIG. 1) using electronic trip units 35 is disclosed. The electronic trip units 35 are coupled to a communications bus 30 whereby the electronic trip units 35 can be reconfigured, controlled, and/or monitored by a central computer. Further, the electronic trip units 30 include a data acquisition circuit 100 (FIG. 4) that uses chopping to provide better accuracy and increased dynamic range of current measurements.

Claims

1. A data acquisition system for a circuit breaker, comprising:

a signal source providing a source signal;

a microprocessor;

a signal conditioning circuit coupled to the microprocessor and configured to receive a periodic signal from the microprocessor; and

a chopping circuit coupled to the signal conditioning circuit and coupled to the signal source, the chopping circuit configured to chop the source signal in response to the periodic signal.

2. The data acquisition system of claim 1 wherein the signal conditioning circuit includes an application specific integrated circuit.

3. The data acquisition system of claim 1 wherein the periodic signal is a pulsed signal.

4. The data acquisition system of claim 1 wherein the chopping circuit includes,

a measurement branch coupled to the signal source;

and

a switching branch coupled to the signal conditioning circuit and coupled to the signal source,

wherein the switching branch is switched in response to the periodic signal and measurement, across the measurement branch, is carried out in response to the periodic signal.

5. The data acquisition system of claim 4 wherein the measurement branch includes a resistive element.

6. The data acquisition system of claim 4 wherein the switching branch provides at least a partial short circuit of the source signal.