Security system and method for revenue class electricity meter

• US 6,000,034 A
• Filed: 05/06/1997
• Issued: 12/07/1999
• Est. Priority Date: 05/06/1997
• Status: Expired due to Term

• Current Assignee: Power Measurement Ltd. (Schneider Electric SE)
• Original Assignee: Power Measurement Ltd. (Schneider Electric SE)
• Inventors: Teachman, Michael, Ki, Simon C. S., Lightbody, Simon, Giles, David W.
• Primary Examiner(s): Donaghue, Larry D.
• Application Number:
  US08/851,941
• Time in Patent Office: 945 Days
• Field of Search: 324/110, 324/156, 702/60, 702/62, 702/64, 395/186, 395/188.01, 340/870.02, 379/106.07, 713/200, 713/202
• US Class Current: 726/21
• CPC Class Codes: G01R 22/066 Arrangements for avoiding or indicating fraudulent use
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: G07F 15/003 for electricity
• CPC Class Codes: G07F 15/08 with means for varying the tariff or changing the price

Abstract

A security system for programmable revenue class electricity meters. Each programmable revenue class electricity meter includes a metering portion or stage that couples to a power line. The metering portion is responsive to and senses the electricity in the power line and provides a digital output. The programmable revenue class electricity meter includes a processor that runs programming that records, calculates, and/or stores data relating to the electricity sensed by the metering portion. In particular, the programming records, calculates, and/or stores revenue-related data that can be used for calculating charges for the electricity. The programming can be changed by authorized persons to modify the types of data that can be measured, calculated, recorded, displayed, communicated, and/or stored for any desired purpose and in particular for revenue-related purposes. Modification of the programming and access to information is limited to authorized persons by means of the security system. The security system includes security system programming in the meter that checks for a code word that is required to be input prior to any changes to the revenue-related programming can be effected. The security system programming compares the input code word to a code word stored in the meter and unlocks restrictions on modification of the revenue-related programming if the input code word matches the stored code word.

Claims

1. A revenue-class electricity meter comprising:

a sensing portion that couples to an electrical power line and that is responsive to electricity in the power line, said sensing portion providing a digital output indicative of the electricity in said power line;

a processor;

a revenue-related program code segment adapted to run on said processor, said revenue-related code segment comprising revenue-related meter functions that generate revenue-related data stored in a memory of said meter; and

a configurable non-revenue-related program code segment adapted to run on said processor, said non-revenue-related program code segment comprising non-revenue-related meter functions, wherein said non-revenue-related code segment permits user-modification of said non-revenue-related functions;

a security program code segment adapted to run on said processor to permit modification of said revenue-related data, said security program including a function that receives an input code, compares the input code to a stored code in a memory of the meter, and unlocks restrictions preventing modification of said revenue-related data if said input code matches said stored code and wherein said non-revenue-related program code segment permits modification of said non-revenue-related functions independent of said security program.

2. The invention of claim 1 further comprising:

a housing having an interior in which said processor is located;

a removable cover providing access to said interior of said housing; and

a mechanical sealing arrangement coupling said removable cover to said housing, said mechanical sealing arrangement providing a visual indication of removal of said removable cover.

3. The invention of claim 2 wherein said mechanical sealing arrangement comprises a lead ring.

4. The invention of claim 2 wherein said mechanical sealing arrangement comprises:

a first tab located on said housing, said first tab having a first opening located therein;

a second opening located on said removable cover, said first tab extending through said opening; and

a ring extending through the first opening in said first tab to prevent removal of said removable cover from said housing without breaking of said ring.

5. The invention of claim 1 wherein said input code is stored on a removable card that can be installed in a slot inside said meter.

6. The invention of claim 5 wherein said card comprises a printed circuit board having a memory located thereon, and further wherein said input code is stored in said memory.

7. The invention of claim 1 wherein said input code is downloaded in a message over a data network to which said meter is coupled.

19. The meter of claim 1 comprising at least one jumper disposed within said meter that provides said input code.

26. The invention of claim 1 wherein the input code is encrypted.

27. The invention of claim 7 wherein the input code is encrypted.

8. In combination:

(1) a revenue-class electricity meter comprising;

a metering portion that couples to an electrical power line and that is responsive to electricity in the power line, said metering portion providing a digital output indicative of the electricity in said power line;

a processor;

a first program run on the processor and responsive to the digital output of the metering portion, said first program having revenue-related functions that generate revenue-related values and non-revenue-related functions that generate non-revenue-related values using configurable program modules; and

a slot coupled to said processor for receiving a programming key; and

(2) a programming key adapted to be installed in said slot, said programming key including a memory having a code expression stored therein and preventing modification of said revenue-related functions in the absence of said code expression and said non-revenue-related functions being capable of being modified irrespective of the presence of said code expression.

9. A security system for a plurality of revenue-class electricity meters, wherein each of said plurality of revenue-class electricity meters comprises:

a sensing portion that couples to an electrical power line and that is responsive to electricity in the power line, said sensing portion providing a digital output indicative of the electricity in said power line;

a processor;

a first program run on the processor and responsive to the digital output of the sensing portion memory, said first program including a first code segment adapted to provide at least one revenue-related function that generates at least one revenue-related value and a second, configurable non-secure code segment that provides at least one non-revenue-related function that generates at least one non-revenue-related value, said second code segment configured to permit user-modification of at least one non-revenue-related function;

a second program adapted to modify said first program, said second program including a function that checks for the presence of a function code and prevents modification of the revenue-related functions of said first program in the absence of said code, the non-revenue-related functions being configurable by a user irrespective of the presence of said code;

a slot coupled to said processor for receiving a programming key; and

a programming key adapted to be used in each revenue-class electricity meter of said plurality of revenue-class electricity meters, said programming key providing said code.

10. The invention of claim 9 wherein each revenue class electricity meter of said plurality of revenue class security meters, further comprises:

a housing having an interior in which said slot is located;

a removable cover providing access to said interior of said housing; and

a mechanical sealing arrangement coupling said removable cover to said housing, said mechanical sealing arrangement providing a visual indication of removal of said removable cover.

11. The invention of claim 10 wherein said mechanical sealing arrangement comprises a lead ring.

12. The invention of claim 10 wherein said mechanical sealing arrangement comprises:

a first tab located on said housing, said first tab having a first opening located therein;

an second opening located on said removable cover, said first tab extending through said opening; and

a ring extending through the first opening in said first tab to prevent removal of said removable cover from said housing without breaking of said ring.

13. A method of operating a plurality of revenue-class electricity meters, comprising the steps of:

providing a first program run on a processor in said plurality of revenue-class electricity meters responsive to the digital output of a metering portion of a memory, said first program providing revenue-related functions that generate revenue-related values and configurable non-revenue-related functions that generate non-revenue-related values, and

locking said first program to prevent modification of said revenue-related functions in the absence of a key;

providing a key, said key unlocking said first program to permit modification of said revenue-related functions and said non-revenue-related functions being capable of being configured irrespective of the presence of said key;

obtaining access to an interior of a housing of a revenue-class electricity meter;

installing said key;

operating a program to modify revenue-related values in the programming of the revenue-class electricity meter, wherein said program checks that the key has been installed;

removing the key from said revenue-class electricity meter; and

closing the housing of the revenue-class electricity meter to prevent access to the interior thereof.

14. The invention of claim 13 further comprising the step of:

after the step of closing the housing of the revenue class electricity meter, installing a sealing arrangement on said housing of the revenue class electricity meter, said sealing arrangement preventing access to the interior of said housing.

15. The invention of claim 13 further comprising the step of:

after the step of closing the housing of the revenue class electricity meter, installing a sealing arrangement on said housing of the revenue class electricity meter, said sealing arrangement providing a visual indication if the housing is reopened.

16. The invention of claim 13 further comprising the step of:

after the step of closing the housing of the revenue class electricity meter, obtaining access to an interior of a housing of a second revenue class electricity meter;

installing the programming key into a connector located inside said housing of said second revenue class electricity meter;

operating a program to modify revenue-related values in the programming of second revenue class electricity meter, wherein said program checks that the programming key has been installed;

removing the programming key from said second revenue class electricity meter; and

closing the housing of the second revenue class electricity meter to prevent access to the interior thereof.

17. The method of claim 13 wherein said step of installing a key comprises using at least one jumper.

18. The method of claim 13 wherein the step of installing a key comprises using a removable program card that is received into a connector in said electricity meter and includes a memory having said key in the form of a code stored therein.

20. In combination:

a revenue-class electricity meter comprising;

a metering portion that couples to an electrical power line and that is responsive to electricity in the power line, said metering portion providing a digital output indicative of the electricity in said power line;

a processor;

a first program run on the processor and responsive to the digital output of the metering portion, said first program adapted to provide revenue-related functions that generate revenue-related values and non-revenue-related functions that generate non-revenue-related values using configurable program modules; and

a key code, wherein said revenue-related functions are locked to prevent modification thereof in the absence of said key code and said non-revenue-related functions being capable of being modified irrespective of the presence of said key code.

21. The combination of claim 20 comprising at least one jumper disposed within said meter, said jumper providing said key code.

22. The combination of claim 20 comprising a programming key adapted to be installed in said meter, said programming key including a memory having said key code located therein.

23. A security system for a plurality of revenue-class electricity meters, wherein each of said plurality of revenue-class electricity meters comprises:

a sensing portion that couples to an electrical power line and that is responsive to electricity in the power line, said sensing portion providing a digital output indicative of the electricity in said power line;

a processor;

a key code adapted for use in each revenue-class electricity meter of said plurality of revenue-class security meters;

a first program run on the processor and responsive to the digital output of the sensing portion memory, said first program including a first code segment adapted to provide at least one revenue-related function that generates at least one revenue-related value and a second, configurable non-secure code segment that provides at least one non-revenue-related function that generates at least one non-revenue-related value, said second code segment permitting user-modification of said at least one non-revenue-related function; and

a second program adapted to modify said first program, said second program including a function that checks for the presence of a key code and prevents modification of said at least one revenue-related function of said first program in the absence of said key code, the at least one non-revenue-related function being configurable by a user irrespective of the presence of said key code.

24. The security system of claim 23 comprising at least one jumper disposed within each of said meters, said jumper providing said key code.

25. The security system of claim 23 comprising a programming key adapted to be installed in each of said meters, said programming key including a memory having said key code located therein.