Reverse wiring detect in circuit interrupting devices

• US 6,937,452 B2
• Filed: 01/23/2004
• Issued: 08/30/2005
• Est. Priority Date: 02/03/2003
• Status: Active Grant

• Current Assignee: Leviton Manufacturing Company Incorporated
• Original Assignee: Leviton Manufacturing Company Incorporated
• Inventors: Campolo, Steve, Chan, David
• Primary Examiner(s): Jackson, Stephen W.
• Assistant Examiner(s): KITOV, ZEEV V
• Application Number:
  US10/762,377
• Publication Number:
  US 20040257725A1
• Time in Patent Office: 585 Days
• Field of Search: 361/42, 361/45, 361/82, 361/76, 361/77
• US Class Current: 361/42
• CPC Class Codes: H02H 3/338 also responsive to wiring error, e.g. loss of neutral, break

Abstract

A resettable circuit interrupting device having a switch and timer circuit connected to the line side of the interrupting device to cause a leakage current to flow for a defined interval of time when power is applied. The timer and switch circuit comprises a timer powered by current from the phase leg of the device which is designed to operate for a defined interval of time. The timer starts operating when power is applied to the circuit interrupting device and normally continues to operate for the defined interval to time. Upon completion of the timed interval, the timer turns itself off and stays off until power is again applied to the device after an interruption. When power is first applied to the interrupting device, the timer is energized from the phase leg and causes the switch to close which connects the neutral leg on the line side of the interrupting device to a ground terminal. If the device is not reverse wired, the timer continues to operate and the switch remains closed until the timer completes its cycle, at which time the switch opens and the neutral leg of the device is no longer connected to the ground terminal. If the device is reverse wired, then at some instant after the switch is closed the device will sense a reverse wired fault, the switches SW1 and SW2 will open, and line power will be disconnected from the interrupting device.

Claims

1. A circuit interrupting device having a detection circuit, at least one pair of load terminals and at least one pair of line terminals, the circuit interrupting device comprises:

a switch and timer circuit coupled to the line terminals so as to allow a sufficient amount of leakage current to flow for a sufficient amount of time to trip the circuit interrupting device when such device is reverse wired,

wherein the switch of the switch and timer circuit is coupled to connect the neutral leg on the line side to a ground terminal to cause a leakage current to flow to trip the device if the device is reverse wired.

2. The device of claim 1 wherein the switch of the switch and timer circuit is coupled to connect the neutral leg on the line side to a ground terminal to cause a leakage current to flow which does not trip the device if it is not reverse wired.

3. The device of claim 1 wherein the device is self tripped if reverse wired upon the application of power.

4. The device of claim 1 wherein the switch of the switch and timer circuit is initially conditioned to be closed for an interval of time that is greater than 0.3 seconds and less than 20 seconds.

5. The device of claim 4 wherein the interval of time is greater than 0.5 seconds and less than 15 seconds.

6. The device of claim 4 wherein the interval of time is greater than 0.5 seconds and less than 10 seconds.

7. The device of claim 4 wherein the interval of time is greater than 0.5 seconds and less than 7 seconds.

8. The device of claim 4 wherein the interval of time is greater than 2 seconds and less than 7 seconds.

9. The device of claim 1 wherein the timer of the switch and timer is coupled to receive power from the phase leg of the device.

10. The device of claim 9 wherein the timer is coupled to close the switch for a defined interval of time when the device is not reverse wired.

11. The device of claim 10 wherein the timer operates to open the switch prior to the defined interval of time when the device is reverse wired.

12. The device of claim 10 wherein the timer operates to close the switch one time when power is first applied after an off time.