ELECTRICAL SWITCHING MODULE

• US 20110115460A1
• Filed: 03/31/2010
• Published: 05/19/2011
• Est. Priority Date: 11/13/2009
• Status: Active Grant

• Current Assignee: Leviton Manufacturing Company Incorporated
• Original Assignee: Leviton Manufacturing Company Incorporated
• Inventors: Parsons, Kevin, Elliott, Randall B., Hick, Robert L., Leinen, Richard A., Muthu, Subramanian
• Granted Patent: US 8,755,944 B2
• Time in Patent Office: Days
• US Class Current: 323/285
• CPC Class Codes: H01H 50/02 Bases; Casings; Covers frames for mounting two or more relays or for mounting a relay and another electric component H02B1/01, H04Q1/08, H05K
• CPC Class Codes: H01H 50/026 Details concerning isolation between driving and switching circuit
• CPC Class Codes: H01H 50/047 Details concerning mounting a relays
• CPC Class Codes: H03K 17/082 by feedback from the output to the control circuit
• CPC Class Codes: H03K 17/13 Modifications for switching at zero crossing generating an impulse at zero crossing H03K5/1536
• CPC Class Codes: H03K 17/605 with galvanic isolation between the control circuit and the output circuit H03K17/78 takes precedence
• CPC Class Codes: H03K 17/689 with galvanic isolation between the control circuit and the output circuit H03K17/78 takes precedence
• CPC Class Codes: H03K 17/78 using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled

Abstract

A module including a case; an electrical switching device configured to control power to a load; and a controller coupled to the electrical switching device. The electrical switching device and the controller are substantially encapsulated by the case. Functionality of the module can be exposed through a communication interface in the case.

Claims

1. A module, comprising:

a case;

an electrical switching device configured to control power to a load;

a controller coupled to the electrical switching device;

wherein the electrical switching device and the controller are substantially encapsulated by the case.

2. The module of claim 1, wherein the controller is configured to monitor the electrical switching device.

3. The module of claim 1, further comprising:

a position sensor configured to sense a state of the electrical switching device;

wherein the position sensor is coupled to the controller.

4. The module of claim 3, further comprising:

a manual actuator coupled to the electrical switching device;

wherein the position sensing circuit is configured to sense a position of the manual actuator.

5. The module of claim 1, further comprising a zero-crossing detector coupled to the controller and configured to detect a zero-crossing associated with the electrical switching device.

6. The module of claim 1, further comprising a current sensor coupled to the controller and configured to sense a current associated with the electrical switching device.

7. The module of claim 1, further comprising a voltage sensor coupled to the controller and configured to measure a voltage associated with the electrical switching device.

8. The module of claim 1, further comprising:

a terminal configured to receive a signal; and

a communication interface coupled to the controller;

wherein the controller is configured to determine a parameter for the communication interface in response to the signal at the terminal.

9. The module of claim 1, further comprising a dimming interface coupled to the controller and configured to provide dimming control to the load.

10. The module of claim 9, wherein:

the dimming interface is disposed on a first voltage region of the case; and

the controller is disposed in a second voltage region substantially isolated from the first voltage region.

11. The module of claim 1, further comprising:

a communication interface;

wherein the controller is configured to expose functionality of the electrical switching device through the communication interface.

12. The module of claim 1, the electrical switching device and the load referred to as a first electrical switching device and a first load, the module further comprising:

a second electrical switching device configured to control power to a second load;

wherein the second electrical switching device is substantially encapsulated by the case.

13. The module of claim 12, wherein:

the first electrical switching device is substantially encapsulated within a first chamber of the case;

the second electrical switching device is substantially encapsulated within a second chamber of the case; and

the first chamber is substantially isolated from the second chamber.

14. The module of claim 13, further comprising:

a controller coupled to the first electrical switching device and the second electrical switching device and substantially encapsulated by the case;

wherein the controller is substantially isolated from the first chamber and the second chamber.

15. The module of claim 12, further comprising:

a first manual actuator coupled to the first electrical switching device;

a first position sensing circuit configured to sense a position of the first manual actuator;

a second manual actuator coupled to the second electrical switching device; and

a second position sensing circuit configured to sense a position of the second manual actuator.

16. A method comprising:

sensing an attribute associated with an electrical switching device substantially encapsulated in a case;

communicating the sensed attribute through a communication interface of the case; and

exposing functionality of the electrical switching device through the communication interface.

17. The method of claim 16, further comprising:

actuating the electrical switching device; and

sensing a state of the electrical switching device.

18. The method of claim 16, further comprising detecting a zero-crossing associated with the electrical switching device.

19. The method of claim 16, further comprising detecting a voltage associated with the electrical switching device.

20. The method of claim 16, further comprising detecting a current associated with the electrical switching device.

21. The method of claim 16, further comprising:

measuring a voltage on a terminal; and

determining a parameter for the communication in response to the measured voltage.

22. The method of claim 16, further comprising outputting a dimming control signal from the case.

23. A circuit comprising:

a pulse width modulated (PWM) signal generator configured to generate a PWM signal having a pulse width corresponding to an analog signal in a first voltage region of a case;

an isolator spanning the first voltage region and a second voltage region of the case and configured to transfer the PWM signal between the first voltage region and the second voltage region.

24. The circuit of claim 23, wherein:

the isolator includes an actuator;

the pulse width modulator includes;

a charge storage circuit; and

a discharge circuit; and

the actuator is coupled in series with the charge storage circuit and the discharge circuit.

25. The circuit of claim 24, wherein:

the discharge circuit is a current source configured to activate on a first half-cycle of the analog signal; and

the charge storage circuit is configured to store a charge during a second half-cycle of the analog signal.

26. The circuit of claim 23, further comprising:

a zero-crossing detector configured to detect a zero-crossing associated with an electrical switching device;

wherein the PWM signal generator is configured to generate the PWM signal in response to the zero-crossing detector.

27. The circuit of claim 23, further comprising:

a filter configured to convert the PWM signal received through the isolator substantially to another analog signal.

28. The circuit of claim 23, further comprising a controller configured to sense both the analog signal and the zero-crossing in response to the PWM signal transferred through the isolator.

29. The circuit of claim 23, further comprising:

a line voltage terminal configured to receive a line voltage in a first voltage region of a case;

wherein the PWM signal generator is configured to generate the PWM signal with a pulse width corresponding to an amplitude of the line voltage.

30. The circuit of claim 23, further comprising:

a power supply coupled to the isolator and configured to generate a power voltage from a line voltage;

wherein at a minimum specified voltage of the line voltage, the power voltage is substantially equal to a threshold voltage to enable the isolator.

31. A method, comprising:

generating a periodic signal substantially synchronized with zero-crossings associated with an electrical switching device; and

generating a pulse width modulated (PWM) signal in response to the periodic signal;

wherein the PWM signal has a pulse width corresponding to an analog signal.

32. The method of claim 31, further comprising:

propagating the PWM signal through an isolator; and

filtering the PWM signal propagated through the isolator to substantially recover the analog signal.

33. The method of claim 31, further comprising identifying a zero-crossing in response to an edge of the PWM signal.

34. A method comprising:

generating a pulse width modulated (PWM) signal having a pulse width corresponding to a voltage; and

propagating the PWM signal through an isolator.

35. The method of claim 34, further comprising filtering the PWM signal propagated through the isolator.

36. The method of claim 34, further comprising:

lowering a power supply voltage as a line voltage decreases;

disabling the isolator when the line voltage decreases below a threshold in response to the corresponding power supply voltage.