RELATIVE TIME SYSTEM

• US 20100188255A1
• Filed: 01/29/2009
• Published: 07/29/2010
• Est. Priority Date: 01/29/2009
• Status: Active Grant

• Current Assignee: Itron, Inc.
• Original Assignee: Itron, Inc.
• Inventors: Cornwall, Mark
• Granted Patent: US 8,269,649 B2
• Time in Patent Office: Days
• US Class Current: 340/870.20
• CPC Class Codes: G01D 2204/45 Utility meters networked together within a single building
• CPC Class Codes: G01D 4/004 Remote reading of utility meters to a fixed location
• 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

A system, method and device are provided for obtaining, from each endpoint device, meter reading data where the meter reading data are recorded and managed based on a relative time clock in each endpoint device. The relative time clock may be a simple inexpensive clock that tracks minutes and triggers recording of meter reading data for a particular hour at the end of that hour. In that embodiment, a collection system sends an endpoint device a request that includes a requested time that is converted into a relative time so that the endpoint device can understand the request. Since each recorded interval is generated based on a relative time maintained by the clock in the endpoint device rather than an absolute (real) time, the endpoint device does not need to maintain accurate date/time or to read meter reading data from the utility meter based on a real date/time.

Claims

1. A method of obtaining meter reading data from an endpoint device that operates in accordance with a relative time clock, the method comprising:

converting an order time into a relative time;

generating a request including the converted relative time;

transmitting to the endpoint device the generated request;

receiving from the endpoint device a response to the transmitted request, wherein the response includes a set of recorded intervals and wherein the relative time is used by the endpoint device to retrieve the set of recorded intervals; and

processing the response to extract data relevant to the order request.

2. The method of claim 1, wherein the meter reading data is obtained from a utility meter at each time interval that is measured by the relative time clock of the endpoint device.

3. The method of claim 2, wherein the meter reading data obtained at a time interval are recorded to generate a recorded interval;

and

the time interval information and the generated record interval are stored in the endpoint device.

4. The method of claim 2, wherein the relative time clock tracks minutes of each time interval and triggers the generation of a recorded interval at a start of a time interval.

5. The method of claim 4, wherein an interval number is assigned with each recorded interval.

6. The method of claim 5, wherein the interval number indicates the number of time intervals passed from the time when the meter reading data contained in the recorded interval is collected.

7. The method of claim 1, wherein converting the order time includes calculating an offset of interval numbers based on a current time of the collection system and the order time.

8. The method of claim 1, wherein a set of recorded intervals that corresponds to meter reading data collected for each 24 hour is obtained.

9. The method of claim 1, wherein a set of recorded intervals that corresponds to meter reading data collected at a specific time of each day is obtained.

10. An apparatus for obtaining meter reading data from an endpoint device that is configured to operate in accordance with a relative time clock, the apparatus comprising:

a communication unit for obtaining a first request to receive meter reading data from an endpoint device; and

a processing unit operable to;

determine a requested time specified in the first request;

convert the requested time into a relative time that is used by the endpoint device to retrieve a correct set of recorded intervals;

generate a second request including the converted relative time;

cause the communication unit to transmit to the endpoint device the generated second request; and

wherein after the communication unit receives from the endpoint device a response to the transmitted second request, the processing unit processes the response to extract data relevant to the first request.

11. The apparatus of claim 10, wherein the response includes a set of recorded intervals.

12. The apparatus of claim 10, wherein the meter reading data is obtained from a utility meter at each time interval that is measured by a relative time clock of the endpoint device.

13. The apparatus of claim 12, wherein the meter reading data obtained at a time interval are recorded to generate a recorded interval;

and

the time interval information and the generated record interval are stored in the endpoint device.

14. The apparatus of claim 12, wherein the relative time clock tracks minutes of each time interval and triggers generating a recorded interval at a start of a time interval.

15. The apparatus of claim 12, wherein an interval number is assigned with each recorded interval.

16. The apparatus of claim 12, wherein the interval number indicates the number of time intervals passed from the time when the meter reading data contained in the recorded interval was collected.

17. The apparatus of claim 12, wherein converting the order time includes calculating an offset of interval numbers based on the current time of the collection system and the order time.

18. A computer-readable medium having computer-executable components for collecting meter reading data from an endpoint device, the computer-executable components comprising:

a calculating component for calculating the consumption of a utility service over relative time meter readings; and

a consumption collection component operative to;

obtain an order request for an endpoint device;

cause the calculating component to convert an order time into a relative time that is used by the endpoint device to retrieve a correct set of recorded intervals;

generate a request including the converted relative time;

transmit to the endpoint device the generated request;

receive from the endpoint device a response to the transmitted request, wherein the response includes the correct set of recorded intervals; and

process the response to extract data relevant to the order request.

19. The computer-readable medium of claim 18, wherein the calculating component calculates an offset of interval numbers based on the current time of the collection system and the requested time.

20. The computer-readable medium of claim 18, wherein the endpoint device generates each recorded interval according to a relative time clock.