Method and apparatus for indicating meter tampering

• US 6,232,886 B1
• Filed: 12/23/1998
• Issued: 05/15/2001
• Est. Priority Date: 12/23/1998
• Status: Expired due to Term

• Current Assignee: Itron, Inc.
• Original Assignee: Schlumberger Resource Management Services Incorporated (Schlumberger NV)
• Inventors: Morand, Gary W.
• Primary Examiner(s): Horabik, Michael
• Assistant Examiner(s): Edwards, Jr., Timothy
• Application Number:
  US09/220,387
• Time in Patent Office: 874 Days
• Field of Search: 340/870.02, 340/637, 340/635, 340/870.16, 307/132.EA, 700/306, 324/110
• US Class Current: 340/870.02
• CPC Class Codes: G08B 13/1409 for removal detection of electrical appliances by detecting their physical disconnection from an electrical system, e.g. using a switch incorporated in the plug connector

Abstract

Method and apparatus facilitate improved sensing of tampering of an electrically powered device, such as an electric watt-hour meter installed at a residence for metering the amount of electric energy consumed at the residence. The detected tampering involves an effort to remove the electric meter from its power socket, to interrupt the metering of electric energy consumption, or to otherwise gain access for diverting electric energy. Removal of the electric meter from its power socket interrupts power to the meter. The method and apparatus senses motion of the meter and sets a “Tamper Flag” in a non-volatile memory. The “Tamper Flag” is saved (i.e., is not cleared from the non-volatile memory) if loss of power to the meter occurs within a predetermined period of time. The “Tamper Flag” is cleared if there is no loss of power to the meter within the predetermined period of time. Upon detecting a resumption of power after a loss of power to the meter, an indication of sensed tampering is made if the “Tamper Flag” is set.

Claims

1. A method of sensing tampering of an electrically powered meter, including the steps of:

(a) sensing motion of said meter and setting a “

Tamper Flag”

for a predetermined period of time thereafter;

(b) maintaining said “

Tamper Flag”

setting if there is a loss of power to said meter during said predetermined period of time;

(c) clearing said “

Tamper Flag”

if said predetermined period of time passes without loss of power to said meter;

(d) detecting a resumption of power after a loss of power to said meter; and

(e) providing an indication of sensed tampering of said electrically powered meter if said “

Tamper Flag”

is set upon said detection of resumption of power to said meter.

2. A method as in claim 1, wherein said electrically powered meter comprises an electric watt-hour meter, and said sensing motion step includes detecting positional displacement of said meter from a power socket in which it is otherwise intended to be received during normal metering operations thereof.

3. A method as in claim 1, wherein said step of providing an indication of sensed tampering is followed by the step of clearing said “

Tamper Flag” and

recycling said method so as to sense any subsequent tampering of said meter.

4. A method as in claim 3, further including the step of keeping a count of the number of indications of sensed tampering.

5. A method as in claim 1, further including the step of subsequently transmitting to a device external to said meter data of sensed tampering.

6. A method as in claim 5, further including the steps of:

detecting a loss of power to said meter;

determining an amount of previously consumed electrical energy at the time of a detected loss of power; and

subsequently transmitting to a device external to said meter data of previously consumed electrical energy.

7. A method as in claim 1, wherein said predetermined period of time is generally in a range of from about one second to about two minutes.

8. A method as in claim 7, wherein said range is generally from about two seconds to about thirty seconds.

9. A method as in claim 8, wherein said predetermined period of time is about ten seconds.

10. A method of detecting tampering of an electrically powered device, including the steps of:

(a) detecting a displacement of said electrically powered device;

(b) setting a “

Tamper Flag”

responsive to said displacement detecting step;

(c) timing for a predetermined timeout period responsive to said setting “

Tamper Flag”

step;

(d) detecting a loss of power to said electrically powered device;

(e) discontinuing said displacement detecting step and said timing step if a loss of power is detected;

(f) clearing said “

Tamper Flag”

if said timing step runs for the full predetermined timeout period without detection of a loss of power;

(g) detecting a resumption of power after a loss of power;

(h) upon resumption of power, checking whether said “

Tamper Flag”

is set; and

(i) if said “

Tamper Flag”

is set, incrementing a tamper counter and clearing said “

Tamper Flag”

, such that an increased tamper counter reflects the detection of tampering.

11. A method as in claim 10, further including the step of transmitting tamper counter data to an external device so that detection of tampering is indicated relatively remotely from said electrically powered device.

12. A method as in claim 10, wherein said electrically powered device is a utility metering device.

13. A method as in claim 12, further including the step of storing in non-volatile memory energy consumption data of said utility metering device, upon the detection of loss of power thereto.

14. A method as in claim 12, wherein said predetermined timeout period is generally in a range of from about one second to about two minutes.

15. A method as in claim 14, wherein said predetermined timeout period is from about five seconds to about fifteen seconds.

16. A method as in claim 12, wherein said utility metering device is a single phase electric watt-hour meter.

17. A method as in claim 16, wherein said detecting displacement step includes detecting positional displacement of said meter from a power socket in which it is otherwise intended to be received during normal metering operations thereof.

18. Apparatus for sensing tampering of an electrically powered meter, comprising:

non-volatile memory means for the storage of meter associated data therein in the event of loss of power to said meter;

meter motion sensing means for sensing motion of said meter and for outputting a signal indicative thereof;

timer means, responsive to sensed meter motion for establishing the passage of a predetermined period of time after sensing meter motion;

power detecting means for detecting the presence or loss of power to said meter and for outputting corresponding signals thereof; and

logic means, functionally operative with said non-volatile memory means, said meter motion sensing means, said timer means and said power detecting means for functioning such that;

(i) sensing meter motion results in setting of a designated “

Tamper Flag”

in said non-volatile memory means for said predetermined period of time;

(ii) detected loss of power to said meter within said predetermined period of time results in maintaining said “

Tamper Flag”

setting in said non-volatile memory means after such loss of power to said meter;

(iii) detected presence of power to said meter throughout said predetermined period of time results in clearing of said “

Tamper Flag”

in said non-volatile memory means; and

(iv) detected presence of power to said meter after a detected loss of power thereto and while said “

Tamper Flag”

is set results in providing an indication of sensed tampering of said electrically powered meter.

19. An apparatus as in claim 18, wherein:

said electrically powered meter comprises an electric watt-hour meter; and

said meter motion sensing means is operative for detecting positional displacement of said meter from a power socket in which it is otherwise intended to be received during normal metering operations thereof.

20. An apparatus as in claim 18, wherein said meter comprises an electric watt-hour meter and said non-volatile memory means are further functional for storing electric energy consumption data during loss of power to said meter.

21. An apparatus as in claim 18, wherein said logic means comprises dedicated hardware devices.

22. An apparatus as in claim 18, wherein said logic means includes programmable hardware devices using software implemented logic steps.

23. An apparatus as in claim 18, wherein said logic means are further functional, after providing an indication of sensed tampering, for clearing said “

Tamper Flag”

for further tamper sensing operations.

24. An apparatus as in claim 23, further including tamper counter means for keeping data concerning the number of indications of sensed tampering.

25. An apparatus as in claim 18, further including data transmission means for transmitting to a device external to said meter data of sensed tampering.

26. An apparatus as in claim 25, wherein said data transmission means is also operative for transmitting to a device external to said meter data of previously consumed electrical energy as determined by said meter.

27. An apparatus as in claim 18, wherein said predetermined period of time is generally in a range of from about one second to about two minutes.

28. An apparatus as in claim 27, wherein said range is generally from about two seconds to about thirty seconds.

29. An apparatus as in claim 28, wherein said predetermined period of time is about ten seconds.

30. An apparatus for detecting tampering of an electrically powered device, comprising:

position detection means for outputting a device motion signal upon detecting displacement of said device, including setting a tamper flag in memory;

power detecting means for detecting a loss of power to said device and for outputting signals indicative of whether or not power has been lost;

timer means, responsive to setting of said tamper flag and signals of said power detecting means for outputting a predetermined timeout period signal if said tamper flag remains set a predetermined period of time without loss of power; and

logic means, responsive to said timer means and said power detecting means, upon resumption of power after a power loss, for incrementing a tamper count and for clearing said stored tamper flag if said predetermined timeout period signal is not received from said timer means before resumption of power, and for clearing said stored tamper flag without incrementing a tamper count if said predetermined timeout period signal is received from said timer means before resumption of power.

31. An apparatus as in claim 30, wherein said electrically powered device is a utility metering device.

32. An apparatus as in claim 31, wherein said utility metering device is a single phase electric watt-hour meter.

33. An apparatus as in claim 31, further including non-volatile memory means for storage of said tamper flag.

34. An apparatus as in claim 31, wherein said logic means comprises programmable hardware devices using software implemented logic steps.

35. An apparatus as in claim 31, wherein said logic means comprises dedicated hardware devices.

36. An apparatus as in claim 31, wherein:

said metering device comprises an electric watt-hour meter; and

said position detection means comprises means for detecting acceleration of said meter as it is removed from a power socket in which it is otherwise intended to be received during normal metering operations thereof.

37. An apparatus as in claim 31, further including data transmission means for transmitting to an external device data of said tamper count, so that data about detected tampering is indicated relatively remotely from said metering device.

38. An apparatus as in claim 37, further including:

non-volatile memory means for storage of data from said metering device about previously consumed electrical energy; and

wherein said data transmission means is also operative for transmitting to an external device data of such previously consumed electrical energy as stored in said non-volatile memory means.

39. An apparatus as in claim 31, wherein:

said metering device comprises an electric watt-hour meter; and

said position detection means comprises means for detecting positional displacement of said meter from a power socket in which it is otherwise intended to be received during normal metering operations thereof.

40. An apparatus as in claim 39, wherein said position detection means includes a mercury tilt switch and operative circuitry therewith.

41. An apparatus as in claim 31, wherein said predetermined period of time is generally in a range of from about one second to about two minutes.

42. An apparatus as in claim 41, wherein said range is generally from about two seconds to about thirty seconds.

43. An apparatus as in claim 42, wherein said predetermined period of time is about ten seconds.

44. Apparatus for indicating tampering of an electrically powered electric utility metering device, comprising:

non-volatile memory means, operative during loss of power to said metering device, for storing selected data concerning said metering device including a designated “

Tamper Flag,”

meter motion sensing means for sensing motion of said metering device and, responsive thereto, setting said “

Tamper Flag”

in said non-volatile memory means;

power detecting means for alternately detecting the presence and loss of power to said metering device and for outputting corresponding signals indicative thereof;

timer means, responsive to setting of said “

Tamper Flag”

in said non-volatile memory means and operative only while power is present to said metering device, for timing for a predetermined period of time from the setting of said “

Tamper Flag” and

for outputting a predetermined timeout period signal at the successful conclusion of such predetermined period of time;

logic means, operatively associated with said non-volatile memory means, said timer means and said power detecting means, (a) for clearing said “

Tamper Flag”

in said non-volatile memory means if said timer means outputs said predetermined timeout period signal and (b) for outputting a “

Tamper Counter Increment”

signal and subsequently clearing said “

Tamper Flag”

in said non-volatile memory means if said “

Tamper Flag”

is set at a time whenever said logic means receives an indicating signal from said power detecting means indicating the presence of power to said metering device after having received an indicating signal therefrom indicating the loss of power to said metering device;

tamper counter means responsive to said “

Tamper Counter Increment”

signal from said logic means for correspondingly increasing a “

Tamper Counter Value”

thereof; and

data transmission means for transmitting data concerning said “

Tamper Counter Value”

to locations relatively remote from said metering device, such that tampering of said metering device may be relatively remotely indicated.

45. Apparatus as in claim 44, wherein:

said metering device comprises a single phase electric watt-hour meter;

said non-volatile memory means stores electric energy consumption data from said metering device during loss of power thereto; and

said meter motion sensing means comprises means for detecting the positional displacement of said metering device from a power socket in which it is otherwise intended to be received during normal metering operation thereof.

46. Apparatus as in claim 44, wherein said data transmission means comprises one of a wire based communication circuitry and RF based communication circuitry.

47. Apparatus as in claim 46, wherein said timer means comprises one of a dedicated hardware implemented device and a software implemented device.

48. Apparatus as in claim 47, wherein said predetermined period of time is generally in a range of from about one second to about two minutes.

49. Apparatus as in claim 48, wherein said logic means and said tamper counter means are implemented with dedicated hardware.

50. Apparatus as in claim 48, wherein said logic means and said tamper counter means are integrally implemented in programmable hardware using software implemented logic steps.