System for use with polyphase utility meters for recording time of energy use

• US 5,014,213 A
• Filed: 04/20/1988
• Issued: 05/07/1991
• Est. Priority Date: 04/20/1988
• Status: Expired due to Term

• Current Assignee: Cellnet Innovations, Inc.
• Original Assignee: Domestic Automation Company Incorporated
• Inventors: Edwards, Cree A., Johnson, Larsh M.
• Primary Examiner(s): Teska, Kevin J.
• Application Number:
  US07/183,826
• Time in Patent Office: 1,112 Days
• Field of Search: 364/480-483, 364/492, 364/900 MS File, 324/156, 324/113, 324/157, 324/103 R, 324/114, 324/137, 324/74, 324/116, 324/142, 324/139, 340/870.02, 340/870.29, 340/310 A, 340/310 R, 250/231 SE
• US Class Current: 702/62
• CPC Class Codes: G01R 21/133 by using digital technique

Abstract

A system for use with polyphase electric meters having a rotatable disc for recording time of energy use. The system includes a cover, a sensor means, a first module, and a second module. The sensor means detects rotation of the meter disc. The first module is disposed within the confines of the meter cover and includes means for providing power for operation of the system. The second module is releasably mounted to the cover such that disassembly may be accomplished without the use of tools. The second module includes circuit means for determining time of energy use information and storing the same, and for optically transmitting that information to a location external of the meter.

Claims

1. A system for recording time of energy use for use with a polyphase electric meter having a rotatable disc, the system comprising:

a substantially optically transparent cup-shaped cover removably securable to a base of the meter to provide an enclosure for the meter;

sensor means disposed within the confines of said cover and positioned for detecting rotation of the disc and generating a signal in response thereto;

a first module disposed within the confines of said cover and secured to the structure of the meter and electrically connected to said sensor means, said first module including means for providing power for operation of the system; and

a second module releasably mounted to said cover such that disassembly from said cover can be accomplished without the use of tools, said second module including circuit means for determining time of energy use information and storing the same, and for optically transmitting said time of energy use information to a location external of said meter.

2. The system of claim 1 wherein said circuit means includes a microprocessor, a read-only memory for storing a program to control the operation of the microprocessor, and a random-access memory for storing said time of energy use information.

3. The system of claim 1 further including a display means on a front face of said second module and visible through the cover for displaying time of energy use information.

4. The system of claim 1 wherein said second module has a rear panel that is removable without the use of tools for replacement of a backup power supply.

5. The system of claim 1 wherein said sensor means comprises first and second light emitting diodes for directing light toward the disc, and first and second phototransistors for receiving light reflected from the disc and responsive to a change in the reflective index of the disc.

6. The system of claim 1 wherein said first module further includes means for driving said sensor means and amplifying signals therefrom.

7. The system of claim 1 wherein said circuit means includes a microprocessor and means for deriving clock pulses from a main power supply so that said microprocessor is clocked in synchronization with the main power supply.

8. The system of claim 7 wherein said circuit means includes means for providing clock pulses to said microprocessor should power from the main power supply drop below a predetermined value.

9. The system of claim 1 wherein said circuit means further includes a backup source of power for operation of said circuit means should the power supplied by said first module drop below a predetermined value.

10. The system of claim 9 wherein said backup source of power includes a capacitor circuit.

11. The system of claim 1 wherein said sensor means and said first module are mounted on a bracket releasably secured to the meter structure.

12. The system of claim 11 further including means for providing attachment and removal of said first module from said bracket without the use of tools.

13. The system of claim 1 further including a demand reset switch extending through the front face of said cover, the rear of said switch having a cam surface that extends into an opening formed in the front of said second module to operatively engage a normally open switch means such that when said demand reset switch is operated it causes said switch means to close.

14. The system of claim 13 wherein said switch means is a leaf spring switch.

15. The system of claim 1 wherein said second module and said cover include an optical data port for establishing optical communication with a reader means positionable externally of the cover for optically communicating with said circuit means to collect said time of energy use information for calculation of a rate charge for energy use based thereon, said optical data port in said cover projecting outwardly from the front face thereof.

16. The system of claim 15 wherein said reader means is programmed for different rate structures in calculating the rate charge.

17. The system of claim 15 wherein said circuit means includes a light emitting diode and a phototransistor for infrared serial communication of data through said optical data port.

18. The system of claim 17 wherein said reader means includes a light emitting diode and a phototransistor for said infrared serial communication of data.

19. The system of claim 1 wherein said cover and second module include means for releasably mounting said second module to said cover so that said second module may be secured and removed from said cover without the use of tools.

20. The system of claim 19 wherein said means on said cover comprises a substantially U-shaped channel located at opposite sides of said cover and each of said channels having a sloping forward edge.

21. The system of claim 20 wherein said means on said second module includes a tab element formed at opposite sides of said second module for releasably engaging respective ones of said U-shaped channels.

22. The system of claim 21 wherein each of said tab elements include a ramp for engaging said sloping forward edge of said U-shaped channel.

23. A system for recording time of energy use for use with a polyphase electric meter having a rotatable disc, the system comprising:

sensor means disposed within the confines of said meter and positioned for detecting rotation of the disc and generating a signal in response thereto;

a first module disposed within the confines of said meter and secured to the structure of the meter and electrically connected to said sensor means, said first module including means for providing power for operation of the system; and

a second module releasably mounted to a substantially optically transparent cup-shaped cover removably securable to a base of the meter to provide an enclosure such that disassembly of said second module from said cover can be accomplished without the use of tools, said second module including circuit means for determining time of energy use information and storing the same, and for optically transmitting said time of energy use information to a location external of said meter.

24. An apparatus for recording time of energy use for use with a polyphase electric meter, the apparatus comprising:

a substantially optically transparent cup-shaped cover removably securable to a base of the meter;

a module releasably mountable to said cover, said module including circuit means for determining time of energy use information and storing the same, and for optically transmitting said information to a location external of said cover; and

means on said cover and said module for releaseably mounting said module to said cover so that said module is securable and removable from said cover without the use of tools.

25. The apparatus of claim 24 wherein said means on said cover comprises a substantially U-shaped channel located at opposite sides of said cover and each of said channels having a sloping forward edge.

26. The apparatus of claim 25 wherein said means on said module includes a moveable tab element formed at opposite sides of said module for releaseably engaging respective ones of said U-shaped channels.

27. The apparatus of claim 26 wherein each of said tab elements includes a ramp for engaging said sloping forward edge of said U-shaped channels.