Tamper detection apparatus for electrical meters

• US 20070103334A1
• Filed: 11/09/2005
• Published: 05/10/2007
• Est. Priority Date: 11/09/2005
• Status: Active Grant

• Current Assignee: Aclara Technologies LLC (Hubbell, Inc.)
• Original Assignee: Aclara Software, Inc. (ESCO Technologies, Inc.)
• Inventors: Soni, Devendra
• Granted Patent: US 7,432,823 B2
• Time in Patent Office: Days
• US Class Current: 340/870.20
• CPC Class Codes: G01D 4/002 Remote reading of utility meters
• CPC Class Codes: G01R 22/066 Arrangements for avoiding or indicating fraudulent use
• CPC Class Codes: G01R 22/068 Arrangements for indicating or signaling faults
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading

Abstract

Tamper detection apparatus for an electric meter (M) installed at a facility supplied power through an electrical distribution system, the meter being connected to the facility using a receptacle (K) and monitoring electricity usage at the facility for electricity delivered to the facility flowing through the meter. A sensor (RR) senses movement of the meter more than a predetermined amount with respect to the receptacle, whether or not electricity is flowing through the meter, and produces a tampering signal when this occurs. A second and optional sensor (Z) senses the proximity of the meter to its receptacle with removal of meter from its receptacle producing a tampering signal representative thereof. Generation of a tampering signal results in a tamper alert signal being transmitted to the system through a two-way communications path established between the facility and the system.

Claims

1. Tamper detection apparatus for an electric meter installed at a facility supplied power through an electrical distribution system comprising:

an electric meter monitoring electricity usage at the facility and including connection means for connecting the meter into a receptacle installed at the facility, electricity delivered to the facility flowing through the meter;

sensing means for sensing movement of the meter more than a predetermined amount with respect to the receptacle when no electricity is flowing through the meter and for producing a tampering signal representative thereof; and

,

two-way communication means for transmitting an alert signal from the facility to the system to warn of tampering with the meter.

2. The apparatus of claim 1 further including a second sensing means sensing the proximity of the meter to its receptacle with removal of meter from its receptacle producing a tampering signal representative thereof.

3. The apparatus of claim 2 further including a counter to which the tampering signals are supplied, the counter counting tampering signals supplied to it.

4. The apparatus of claim 3 further including means for recording when a tampering event has occurred and for enabling the communications means to transmit an alert signal to the system.

5. The apparatus of claim 4 in which the counter is set to a predetermined count value during installation of the meter at the facility.

6. The apparatus of claim 5 in which the counter is reset by a reset signal transmitted to the meter through the communications means.

7. The apparatus of claim 3 in which the counter does count successive tamper signals supplied for a predetermined interval after a first alert signal is received and counted, so to prevent misleading and false indications of tampering.

8. The apparatus of claim 2 in which each meter has a unique identifier identifying the meter and the location of the facility at which it is installed whereby if two meters are swapped with each other, information regarding the respective meters and their new locations is supplied to the system through the communications means for each meter.

9. The apparatus of claim 1 in which the two-way communications means transmits and receives information through the same lines as those through electricity is supplied to the facility through the meter.

10. The apparatus of claim 1 in which the two-way communications means includes an RF communications path for transmitting and receiving information.

11. The apparatus of claim 1 in which the two-way communications means includes telephonic communications for transmitting and receiving information.

12. The apparatus of claim 1 in which the sensing means includes a tilt sensor which generates the tampering signal when the meter moves more than the predetermined amount with respect to the receptacle.

13. The apparatus of claim 12 in which the tilt sensor comprises a ball switch.

14. The apparatus of claim 13 in which the tilt sensor comprises a reed switch with its associated magnet.

15. The apparatus of claim 13 in which the tilt sensor comprises a mercury switch.

16. The apparatus of claim 13 in which the tilt sensor comprises a conductive liquid filled resistance sensing tilt sensor.

17. The apparatus of claim 13 in which the tilt sensor comprises an accelerometer.

18. The apparatus of claim 13 in which the tilt sensor comprises a piezoelectric sensor.

19. The apparatus of claim 13 in which the sensor comprises a variable resistance branch of a Wheatstone bridge circuit so, when the meter is moved, the sensor moves from a steady state position to a new position changing the resistance between in the branch of the Wheatstone bridge incorporating the sensor, with an alert signal being produced when the meter is moved more than the predetermined distance.

20. The apparatus of claim 2 in which the second sensing means comprises an RFID sensor sensing the proximity of the meter and its receptacle.

21. The apparatus of claim 20 in which the second sensing means comprises a first component housed within the meter M and a second component attached to the receptacle, the first and second components having a communications link between them which is broken if the meter is removed from its receptacle.

22. The apparatus of claim 1 further including a first power source for the meter comprising power supplied to the facility through the meter.

23. The apparatus of claim 22 further including a second power source comprising a capacitor installed within the meter and charged when electricity is flowing through the meter to the facility;

but when the electricity is not flowing, the capacitor supplies power to the sensing means for a predetermined time immediately after the loss of electricity.

24. The apparatus of claim 23 further including a third power source comprising a long life battery capable of providing sufficient power to the sensing means for an extended period of time when power from the first and second said power sources is not available.