| 摘要 |
1,196,199. Automatic control of refrigeration apparatus. HONEY WELL Inc. Dec. 4, 1968 [Dec. 6, 1967], No.57665/68. Heading G3R. A control system for a chilling apparatus comprises a plurality of refrigerator units 13-13<SP>111</SP> arranged in series parallel among which a cooling load is selectively distributed by a digital computer 42 to achieve and optimum power input. The desired water temperature is set by a control 45 which may be a sensor responsive to outdoor temperature the output from which is compared with a signal from an outlet temperature sensor 50. Each unit e.g. 13 comprises a motor 15, condenser 14, and a temperature controller 32, the set point of which is adjusted by computer 42 and compared with an outlet temperature signal from a sensor 33, which adjusts the output of the compressor by a suction damper (not shown). Differential temperature measurements are made at 63, 64 and 55, 60 and forwarded to the computer together with flow measurements at 52, 53, power measurement 31, and inlet temperature measurement 51. This information is compared with a number of preset values stored in the computer, say in the form of a matrix and when identity is reached, signals are sent out e.g. on a line 43 to operate control relays to energize the respective motors. The units 13-13<SP>111</SP> may have equal or unequal outputs. The comparisons are revised say every twenty minutes and the set values are changed at these intervals accordingly. Comparisons of power inputs are also made at these intervals in order to allow for changed performance of each unit. In the embodiment described, only a fraction e.g. 5% of the change is added to the store at each revision so that updating progresses in a more smooth manner than if 100% of the change is added. If such changes exceed a determined amount e.g. 10% of the initial value, an individual or common indicator/alarm 72 may be energized. |
