Voltage indicator test mechanism

• US 8,013,613 B2
• Filed: 12/07/2006
• Issued: 09/06/2011
• Est. Priority Date: 12/08/2005
• Status: Active Grant

• Current Assignee: Grace Technologies, Inc. (WR Grace & Company)
• Original Assignee: Grace Engineered Products, Inc.
• Inventors: Allen, Philip Brown Jr.
• Primary Examiner(s): VALONE, THOMAS F
• Application Number:
  US11/608,087
• Publication Number:
  US 20070132458A1
• Time in Patent Office: 1,734 Days
• Field of Search: 324/523, 324/522
• US Class Current: 324/523
• CPC Class Codes: G01R 19/155 Indicating the presence of voltage
• CPC Class Codes: G01R 35/00 Testing or calibrating of apparatus covered by the other groups of this subclass

Abstract

An electrical safety monitor includes line inputs for an L1, an L2, an L3, and a GND three-phase connections, a line monitoring circuit having a plurality of light indicators and configured to produce light if voltage exists between any two of the line inputs to thereby indicate presence of voltage to a user, and a current generating circuit electrically connected to the line monitoring circuit and adapted to generate a test current to the line inputs to transition the device from dead to live thereby allowing the user to discern between a failure state of the line monitoring circuit and an off state of the line monitoring circuit. The current inducing circuit can include a magnet which induces the test current, stored energy, a photocell, an electroactive material or other means for generating the test current.

Claims

1. An electrical safety monitor, comprising:

line inputs for hardwiring an L1, an L2, an L3, and a GND three-phase connections;

a line monitoring circuit having a plurality of light indicators and configured to produce light if voltage exists between any two of the line inputs to thereby indicate presence of voltage to a user;

a current generating circuit electrically connected to the line monitoring circuit and adapted to generate a test current to the line inputs to transition the electrical safety monitor from dead to live thereby allowing the user to discern between a failure state of the line monitoring circuit and an off state between line inputs.

2. The electrical safety monitor of claim 1 wherein the current generating circuit includes a magnet and the current generating circuit is adapted to induce the test current in response to movement of the magnet.

3. The electrical safety monitor of claim 2 wherein the movement is linear movement.

4. The electrical safety monitor of claim 2 wherein the movement is rotational movement.

5. The electrical safety monitor of claim 1 wherein the current generating circuit includes an electroactive material adapted for transducing mechanical movement into the test current.

6. The electrical safety monitor of claim 5 wherein the electroactive material comprises a piezoelectric element.

7. The electrical safety monitor of claim 1 wherein the current generating circuit includes stored charge circuit adapted for injecting the test current in response to activation of a switch.

8. The electrical safety monitor of claim 1 wherein the current generating circuit includes a photocell adapted for generating the test current.

9. The electrical safety monitor of claim 1 wherein the current generating circuit includes a crank adapted for generating the test current.

10. An improvement to an electrical safety monitor having a line monitoring circuit for monitoring hardwired L1, L2, L3, and GND three-phase line connections and a plurality of indicators for communicating presence of voltage between any of the line connections, the improvement comprising a current inducing circuit electrically connected to the line monitoring circuit and adapted for generating a test current upon activation by a user to transition the line monitoring circuit from dead to live thereby allowing the user to discern between a failure state of the line monitoring circuit and an off state between line inputs.

11. The electrical safety monitor of claim 10 wherein the current generating circuit includes a magnet and the current generating circuit is adapted to induce the test current in response to movement of the magnet.

12. The electrical safety monitor of claim 11 wherein the movement is linear movement.

13. The electrical safety monitor of claim 11 wherein the movement is rotational movement.

14. The electrical safety monitor of claim 10 wherein the current generating circuit includes an electroactive material adapted for transducing mechanical movement into the test current.

15. The electrical safety monitor of claim 14 wherein the electroactive material comprises a piezoelectric element.

16. The electrical safety monitor of claim 10 wherein the current generating circuit includes stored charge circuit adapted for injecting the test current in response to activation of a switch.

17. The electrical safety monitor of claim 10 wherein the current generating circuit includes a photocell adapted for generating the test current.

18. The electrical safety monitor of claim 10 wherein the current generating circuit includes a crank adapted for generating the test current.

19. A method for providing electrical safety monitoring, comprising:

providing an electrical safety monitor having a plurality of solid-state light emitting diodes configured to indicate presence of voltage;

hardwiring the electrical safety monitor to an L1, an L2, an L3, and a GND three-phase connections;

generating a test current to transition the electrical safety monitor from a dead state to a live state to thereby allow a user to discern between a failure state of the electrical safety monitor and an off state between the three-phase connections.

20. The method of claim 19 wherein the step of generating a test current is performed by magnetically inducing the test current.

21. The method of claim 19 wherein the step of generating a test current is performed by converting mechanical movement into the test current.

22. The method of claim 19 wherein the step of generating a test current is performed using stored energy.