Current meter with voltage awareness

• US 10,006,948 B2
• Filed: 01/12/2012
• Issued: 06/26/2018
• Est. Priority Date: 02/25/2011
• Status: Active Grant

• Current Assignee: Veris Industries LLC (Schneider Electric SE)
• Original Assignee: Veris Industries LLC (Schneider Electric SE)
• Inventors: Cook, Martin
• Primary Examiner(s): Astacio-Oquendo, Giovanni
• Application Number:
  US13/349,088
• Publication Number:
  US 20120217954A1
• Time in Patent Office: 2,357 Days
• Field of Search: 324123, 324 7611, 324107, 324127, 702 60, 702 64
• CPC Class Codes: G01R 1/025 concerning dedicated user interfaces, e.g. GUI, or dedicated keyboards G01R31/31912 takes precedence
• CPC Class Codes: G01R 15/183 using transformers with a magnetic core
• CPC Class Codes: G01R 19/2513 Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging
• CPC Class Codes: G01R 21/133 by using digital technique

Abstract

The flexibility of a branch circuit monitor is improved by a signal conditioning unit that outputs a voltage in response to an input voltage and which is configurable to output the same range of output voltages in response to input voltages varying over different ranges.

Claims

1. A branch circuit monitor comprising

(a) a signal conditioning unit including an amplifier producing an output voltage in response to an input voltage,

(b) the signal conditioning unit selectable to produce a minimum output voltage in response to an input voltage of a minimum input voltage and to output a maximum output voltage in response to a first maximum input voltage,

(c) the signal conditioning unit selectable to produce said minimum output voltage in response to an input voltage of said minimum input voltage and said maximum output voltage in response to a second maximum input voltage,

(d) said maximum output voltage of (b) and said maximum output voltage of (c) is the same output voltage, said second maximum input voltage is different than said first maximum input voltage;

(e) said signal conditioning unit providing a range of output voltages between said minimum output voltage and said maximum output voltage when selected in accordance with (b) and providing a range of output voltages between said minimum output voltage and said maximum output voltage when selected in accordance with (c).

2. The branch circuit monitor of claim 1 wherein said first maximum input voltage equals approximately one volt and said second maximum input voltage equals approximately three tenths of a volt.

3. The branch circuit monitor of claim 1 wherein said first maximum input voltage equals approximately one volt and said second maximum input voltage equals approximately five volts.

4. The branch circuit monitor of claim 1 wherein said first maximum input voltage equals approximately one volt and said second maximum input voltage equals approximately ten volts.

5. The branch circuit monitor of claim 1 wherein said signal conditioning unit comprises said amplifier having a variable gain.

6. The branch circuit monitor claim 5 wherein the gain of said amplifier is controlled by a resistance connected to said amplifier and said resistance is manually selected.

7. A branch circuit monitor comprising:

(a) a current transformer including an amplifier producing a transformer voltage quantitatively related to a magnitude of a current in a primary winding of said current transformer, said transformer voltage ranging between a minimum transformer voltage and a maximum transformer voltage;

(b) a signal conditioning unit producing an output voltage in response to said transformer voltage, said output voltage having a magnitude quantitatively related to a magnitude of said transformer voltage,

(c) said signal conditioning unit selectable to produce a minimum output voltage in response to a minimum transformer voltage and a maximum output voltage in response to a first maximum transformer voltage,

(d) said signal conditioning unit selectable to produce said minimum output voltage in response to said minimum transformer voltage and said maximum output voltage in response to a second maximum transformer voltage having a magnitude that is greater than a magnitude of said first maximum transformer voltage, said maximum output voltage of (c) and said maximum output voltage of (d) is the same output voltage;

(e) said signal conditioning unit providing a range of output voltages between said minimum output voltage and said maximum output voltage when selected in accordance with (c) and providing a range of output voltages between said minimum output voltage and said maximum output voltage when selected in accordance with (d);

(f) a data processing unit arranged to calculate a current in said primary winding of said current transformer from said output voltage of said signal conditioning unit.

8. The branch circuit monitor of claim 7 wherein said signal conditioning unit comprises said amplifier having a variable gain.

9. The branch circuit monitor claim 8 wherein the gain of said amplifier is controlled by a resistance connected to said amplifier and said resistance is manually selected.