Monitoring a condenser in a refrigeration system

• US 20070089439A1
• Filed: 10/21/2005
• Published: 04/26/2007
• Est. Priority Date: 10/21/2005
• Status: Active Grant

• Current Assignee: Copeland Cold Chain LP
• Original Assignee: Emerson Retail Services, Inc. (Emerson Electric Company)
• Inventors: Singh, Abtar, Mitchell, James, Woodworth, Stephen
• Granted Patent: US 7,752,854 B2
• Time in Patent Office: Days
• US Class Current: 62/129
• CPC Class Codes: F25B 2500/19 Calculation of parameters
• CPC Class Codes: F25B 2600/111 of condenser fans
• CPC Class Codes: F25B 2700/1931 Discharge pressures
• CPC Class Codes: F25B 2700/21152 at the discharge side of the compressor
• CPC Class Codes: F25B 49/02 for compression type machines, plants or systems

Abstract

A method for monitoring a condenser in a refrigeration system includes calculating a thermal efficiency of the condenser based on operation of the condenser and averaging the thermal efficiency over a predetermined period. Further, the method comprises comparing the average to an efficiency threshold and generating a notification based on the comparison. The method may be executed by a controller or stored in a computer-readable medium.

Claims

1. A method comprising:

calculating a thermal efficiency of a condenser of a refrigeration system based on operation of said condenser;

averaging said thermal efficiency over a predetermined period;

comparing said average to an efficiency threshold; and

generating a notification based on said comparison.

2. The method of claim 1, further comprising receiving at least one of a condenser fan current signal that corresponds to an electrical current of a condenser fan of said condenser, a condenser fan power signal that corresponds to an electrical power of said condenser fan, and a condenser fan control signal, wherein said calculating said thermal efficiency is based on at least one of said condenser fan current signal, said condenser fan power signal, and said condenser fan control signal.

3. The method of claim 1, further comprising receiving at least one of a compressor current signal that corresponds to an electrical current of a compressor of said refrigeration system, a compressor power signal that corresponds to an electrical power of said compressor, and a compressor control signal, wherein said calculating said thermal efficiency is based on at least one of said compressor current signal, said compressor power signal, and said compressor control signal.

4. The method of claim 1, further comprising receiving at least one of a discharge pressure signal that corresponds to a discharge pressure of a compressor of said refrigeration system and a discharge temperature signal that corresponds to a discharge temperature of said compressor, wherein said calculating said thermal efficiency is based on at least one of said discharge pressure signal and said discharge temperature signal.

5. The method of claim 4, further comprising calculating a saturation temperature based on refrigerant type data and at least one of said discharge pressure signal and said discharge temperature signal, wherein said calculating said thermal efficiency is based on said calculated saturation temperature.

6. The method of claim 5, further comprising calculating a difference between said calculated saturation temperature and an ambient temperature, wherein said calculating said thermal efficiency is based on said calculated difference.

7. The method of claim 1, further comprising monitoring a fan speed of a condenser fan of said condenser, wherein said calculating said thermal efficiency is based on said monitored fan speed.

8. The method of claim 1, further comprising calculating said efficiency threshold based on a predetermined percentage of a benchmark thermal efficiency of said condenser.

9. The method of claim 8, wherein said benchmark thermal efficiency corresponds to said thermal efficiency of said condenser when at least one of said condenser is clean and said condenser is initialized.

10. A controller that executes the method of claim 1.

11. A controller that executes the method of claim 2.

12. A controller that executes the method of claim 3.

13. A controller that executes the method of claim 4.

14. A controller that executes the method of claim 5.

15. A controller that executes the method of claim 6.

16. A controller that executes the method of claim 7.

17. A controller that executes the method of claim 8.

18. A controller that executes the method of claim 9.

19. A computer-readable medium having computer-executable instructions for performing the method of claim 1.

20. A computer-readable medium having computer-executable instructions for performing the method of claim 2.

21. A computer-readable medium having computer-executable instructions for performing the method of claim 3.

22. A computer-readable medium having computer-executable instructions for performing the method of claim 4.

23. A computer-readable medium having computer-executable instructions for performing the method of claim 5.

24. A computer-readable medium having computer-executable instructions for performing the method of claim 6.

25. A computer-readable medium having computer-executable instructions for performing the method of claim 7.

26. A computer-readable medium having computer-executable instructions for performing the method of claim 8.

27. A computer-readable medium having computer-executable instructions for performing the method of claim 9.