Refrigeration – Automatic control – Refrigeration producer
Patent
1995-05-25
1996-11-12
Tanner, Harry B.
Refrigeration
Automatic control
Refrigeration producer
62209, 62230, F25B 4104
Patent
active
055728790
ABSTRACT:
A method of controlling refrigerant pressure during elevated ambient temperature conditions in a refrigeration unit having a refrigerant compressor driven by a prime mover, and controllable suction line modulation. The method includes the steps of detecting the actual load PML on the prime mover, sensing the ambient temperature AA, and providing a dynamic load limit DLL as a function of the ambient temperature AA. The actual load PML is compared with the dynamic load limit DLL, and the suction line modulation is changed as a function of the comparison step to cause the actual load PML to follow the changing dynamic load limit DLL. The invention also includes a method of preventing excessive on-off cycling of a refrigeration unit during low ambient temperature conditions, with the refrigeration unit operating in a cycling start-stop mode to control the temperature of a conditioned space to a selected set point temperature SP. The latter method includes the steps of sensing the ambient temperature AA, and comparing the ambient temperature AA with the set point temperature SP. The on-off cycling rate of the refrigeration unit is determined when the comparison step finds the ambient temperature AA has a predetermined relationship with the set point temperature SP. A cycling rate upper limit is provided and compared with the actual on-off cycling rate. The suction line modulation is increased when the comparison step finds the cycling rate has reached the cycling rate upper limit.
REFERENCES:
patent: 3751940 (1973-08-01), Norbeck
patent: 4270361 (1981-06-01), La Barge
patent: 4646534 (1987-03-01), Russell
patent: 4977751 (1990-12-01), Hanson
patent: 4977752 (1990-12-01), Hanson
patent: 5197670 (1993-03-01), Hanson et al.
patent: 5201186 (1993-04-01), Hanson
Gustafson Alan D.
Harrington Robert L.
Tanner Harry B.
Thermo King Corporation
LandOfFree
Methods of operating a refrigeration unit in predetermined high does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Methods of operating a refrigeration unit in predetermined high , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods of operating a refrigeration unit in predetermined high will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-554972