Method of and system for accumulating verifiable energy demand data from remote electricity meters

• US 4,697,182 A
• Filed: 04/09/1986
• Issued: 09/29/1987
• Est. Priority Date: 09/16/1985
• Status: Expired due to Term

• Current Assignee: Itron Electricity Metering, Inc. (Itron, Inc.)
• Original Assignee: Sangamo Weston, Inc. (Atos SE)
• Inventors: Swanson, Scott C.
• Primary Examiner(s): MYRACLE, JERRY
• Application Number:
  US06/849,899
• Time in Patent Office: 538 Days
• Field of Search: 340/310 A, 340/870.3, 340/870.2, 340/637, 179/2 AM, 364/483, 324/433, 307/66
• US Class Current: 340/870.02
• CPC Class Codes: G01R 11/16 Adaptations of counters to electricity meters
• CPC Class Codes: G01R 11/64 Maximum meters, e.g. tariff for a period is based on maximum demand within that period
• CPC Class Codes: G01R 21/008 Measuring maximum demand
• CPC Class Codes: G01R 21/1338 Measuring maximum demand
• CPC Class Codes: G01R 22/00 Arrangements for measuring time integral of electric power or current, e.g. electricity meters
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm

Abstract

A solid state electricity demand recorder (10) is controlled by a programmable microprocessor (38) to obtain energy demand survey and billing data. The accumulated count of pulses during a record interval is compared with an encoded register reading obtained from an electricity meter (30) at the end of the reord. If there is acceptable correlation between the accumulated count and encoded meter reading, the interval pulse counts associated with that record are deemed verified. Power for the recorder (10) is obtained from the power line, except during power outages in which case a battery (28) provides back-up power. Error conditions such as power outages, meter failure, and low battery condition are automatically detected and communicated to the central computer for remedial action by the electrical utility.

Claims

1. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a telephone line at periodic time intervals;

error condition detecting means for detecting the existence of an eror condition in said system, said error condition corresponding to a meter error, and further comprising timing means responsive to pulses detected by said detecting means for indicating said meter error in response to the failure by said detecting means to detect a pulse within a predetermined time period, and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said telephone line.

2. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a telephone line at periodic time intervals;

an auxiliary battery power supply for supplying power to the system;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a low battery condition of said auxiliary battery power supply, and further comprising low battery circuit means for detecting when the output voltage of said auxiliary battery power supply falls below a predetermined threshold magnitude and for providing a low battery signal to signal said error condition; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said telephone line.

3. The system of claim 2, further comprising clock means for maintaining time data corresponding to the current time of day and date, and memory means for storing time data corresponding to the time of day and date at which said low battery circuit means provides said low battery signal, and wherein said transmitting means transmits said stored time data to said central computer.

4. The system of claim 3, wherein said transmitting means is operative to automatically dial said central computer in response to said low battery signal.

5. The system of claim 2, further comprising command means for receiving control commands from a central computer over telephone lines.

6. The system of claim 5, further comprising enabling means for rendering said low battery circuit means operative, and wherein said enabling means is responsive to a command received by said command means for rendering said low battery circuit operative.

7. The system of claim 6, wherein said enabling means is rendered inoperative by said low battery signal, whereby said low battery circuit is not rendered operative until a new command from said central computer after correction of the low battery condition.

8. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a telephone line at periodic time intervals;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a power outage, and further comprising outage detecting means for detecting the occurrence of a power outage comprising means responsive to the power line frequency for timing the interval between power line cycles, and means responsive to the timing means to provide a power outage signal in response to the failure of said timing means to detect a power line cycle within a predetermined maximum time period; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said telephone line.

9. The system of claim 8, wherein said maximum time period corresponds to a predetermined number n of power line cycles, whereby power outages less than a particular predetermined time do not cause an indication of a power outage.

10. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting meand during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a telephone line at periodic time intervals;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a power outage, and further comprising outage detecting means for detecting the occurrence of a power outage, and an auxiliary battery power supply for supplying power to said system during said power outage; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said telephone lines, wherein said transmitting means is operative to transmit information corresponding to the detection of said outage condition after restoration of power to avoid power drain on said auxiliary battery power supply during said outage.

11. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by same meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a communications channel at periodic time intervals;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a meter error, and further comprising timing means responsive to pulses detected by said detecting means for indicating said meter error in response to the failure by said detecting means to detect a pulse within a predetermined time period; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said communications channel.

12. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a communications channel at periodic time intervals;

an auxiliary battery power supply for supplying power to the system;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a low battery condition of said auxiliary batery power supply, and further comprising low battery circuit means for detecting when the output voltage of said auxiliary battery power supply falls below a predetermined threshold magnitude and for providing a low battery signal to signal said error condition; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said communications channel.

13. The system of claim 12, further comprising clock means for maintaining time data corresponding to the current time of day and date, and memory means for storing time data corresponding to the time of day and date at which said low battery circuit means provides said low battery signal, and wherein said transmitting means transmits said stored time data to said central computer over said communications channel.

14. The system of claim 13, wherein said transmitting means is operative to automatically communicate with said central computer in response to said low battery signal.

15. The system of claim 12, further comprising command means for receiving control commands from a central computer over said communications channel.

16. The system of claim 15, further comprising enabling means for rendering said low battery circuit means operative, and wherein said enabling means is responsibe to a command received by said command means for rendering said low battery circuit operative.

17. The system of claim 16, wherein said enabling means is rendered inoperative by said low battery signal, whereby said low battery circuit is not rendered operative until a new command from said central computer after correction of the low battery condition.

18. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a communications channel at periodic time intervals;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a power outage, and further comprising outage detecting means for detecting the occurrence of a power outage including means responsive to the power line frequency for timing the interval between power line cycles, and means responsive to the timing means provide a power outage signal in response to the failure of said timing means to detect a power line cycle within a predetermined maximum time period; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said communications channel.

19. The system of claim 18, wherein said maximum time period corresponds to a predetermined number n of power line cycles, whereby power outages less than a particular predetermined time do not cause an indication of a power outage.

20. A system for accumulating energy demand data from an electricity meter of a type having means for generating pulses corresponding to a demand rate, comprising:

means for detecting pulses generated by said meter;

means for counting the pulses detected by said detecting means during a predetermined measurement interval to develop demand data;

memory means for storing said demand data during predetermined time intervals;

means for transmitting stored demand data from said memory means to a central computer over a communicaions channel at periodic time intervals;

error condition detecting means for detecting the existence of an error condition in said system, said error condition corresponding to a power outage, and further comprising outage detecting means for detecting the occurrence of a power outage, and an auxiliary battery power supply for supplying power to said system during said power outage; and

means responsive to said error condition for transmitting information corresponding to said error condition to said central computer over said communications channel, wherein said transmitting means is operative to transmit information corresponding to the detection of said outage condition after restoration of power to avoid power drain on said auxiliary battery power supply during said outage.