Question 87Refrigeration & AC - QMED
70% to passWhat is the purpose of the low-pressure cut-out switch as used as a primary controller for a refrigeration system or unit?
Amaintain a preset suction pressure to the compressor
Bmaintain a preset low-side pressure for the system
Cstart and stop the compressor as needed
Dcontrol the capacity of the compressor
AI Explanation
The correct answer is C) start and stop the compressor as needed. The low-pressure cut-out switch is a safety device used in refrigeration systems to prevent damage to the compressor. It is designed to automatically shut off the compressor when the suction pressure drops below a pre-set, safe level. This prevents the compressor from operating under a vacuum, which could lead to mechanical damage. The low-pressure cut-out switch is considered a primary controller as it directly controls the operation of the compressor based on the system's low-side pressure. The other options are incorrect as they do not accurately describe the primary function of this safety device.
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