Refrigeration unit high and low pressure controller

I. High and low pressure controller

High and low pressure controllers in cold storage refrigeration units are key components in the refrigeration system used to monitor and control refrigerant pressure, they ensure that the refrigeration cycle operates within a safe and effective pressure range.

High pressure controller

Role: Used to control the high pressure or exhaust pressure. When the pressure in the system exceeds the set safety value, the high pressure controller will shut down the compressor to prevent the excessive pressure from damaging the system or causing safety problems.

Application Scenario: When the air-cooled condenser air volume is insufficient or cut off, when the water-cooled condenser water volume is insufficient or the water temperature is too high, or when the water is cut off, or when the high-pressure pressure exceeds the set value of the pressure controller due to other reasons, the controller jumps open and breaks the circuit of the contactor, so the compressor stops and protects the system.

Low Pressure Controller

Role: Used to control the low pressure or suction pressure. If the pressure in the system falls below the normal operating range, the low pressure controller will stop the compressor to avoid the compressor running under inefficient or unstable conditions, which may result in damage to the compressor or poor lubrication of the refrigeration oil.

Application Scenario: When the system lacks refrigerant, or meets blockage, forgets to open the valve, or the heat load is too low, and other reasons that cause the low pressure to be too low, the controller trips, breaks the circuit of the contactor, and stops the compressor, protects the compressor from running at too low a pressure, and improves the economy of the system's operation.

Second, oil pressure controller

Cold storage refrigeration unit in the oil pressure controller is specifically designed to monitor and control the compressor internal lubricant pressure of the key components.

Role: in the refrigeration system, the compressor needs lubricant to lubricate its moving parts, such as bearings and pistons, in order to reduce wear and ensure smooth operation. The main function of the oil pressure controller is to monitor the oil pressure generated by the oil pump and compare it with the refrigerant pressure on the suction side of the compressor. If the oil pressure falls below a set minimum value or if the oil pressure differential is insufficient, the controller triggers a safety mechanism, such as cutting off power to the compressor, to prevent damage to the compressor due to poor lubrication.

Application Scenario: The oil pressure controller can be connected to an alarm system to sound an alarm when the oil pressure or oil pressure differential falls below a safety threshold, alerting maintenance personnel to carry out inspections and necessary repairs.

Third, temperature controller

Temperature controller is a controller used to control the temperature, such as cold storage temperature controller, freezer temperature controller.

Role: Temperature controllers control heating or refrigeration equipment to maintain the target temperature by measuring the temperature signal and then comparing it with the preset temperature.

Application Scenario: Temperature controllers are widely used in various refrigeration equipment to ensure product quality, productivity and energy utilization.

Working Principle: The temperature controller measures the temperature signal and compares it with the preset temperature to determine whether the current temperature is within the target range. If the current temperature is lower than the target temperature, the temperature controller will turn on the heating equipment to increase the temperature; if the current temperature is higher than the target temperature, the temperature controller will turn off the heating equipment and start the refrigeration equipment to reduce the temperature. In this way, the temperature controller can control the temperature stably to meet different production needs.