1. Key Technical Specifications Measuring medium: R134a, R404A, R290 refrigerants Measuring range: Low pressure 0–1.8MPa; High pressure 0–4.2MPa Operating temperature: -40℃ ~ +125℃ with full-range temperature compensation Measurement accuracy: ±0.6%FS ~ ±1.6%FS Response time: ≤12ms Ingress protection: IP67 anti-refrigerant corrosion, dustproof and waterproof Supply voltage: 5VDC standard power supply Vibration resistance: 10–25g, adapts to bumpy vehicle transportation Service lifespan: More than 3 million pressure cycle tests 2. Core Function Continuously track refrigerant pressure of vehicle refrigerator during cooling operation. Over-high pressure protection: cut off the compressor to prevent pipeline rupture and unit damage. Over-low pressure protection: shut down the compressor to avoid dry burning caused by refrigerant leakage. Feed pressure signals to the control panel to intelligently adjust fan speed and cooling capacity for stable cargo compartment temperature. Built-in self-diagnosis function detects circuit open/short circuit and refrigerant leakage, outputs fault signals and stores fault codes. 3. Working Principle The sensor adopts piezoresistive sensing principle: Refrigerant pressure pushes the anti-corrosion sensitive diaphragm to produce tiny elastic deformation. Integrated strain resistors create linear resistance changes corresponding to pressure values. Wheatstone bridge converts resistance fluctuation into standard analog voltage signals. Internal filtering and temperature compensation circuits eliminate environmental interference and output stable signals to the refrigeration controller. 4. Application Scope Vehicle Types Refrigerated trucks, refrigerated vans, cold chain logistics vehicles, RV refrigerators, insulated transport vehicles. Equipment Engine-driven refrigeration units and electric refrigeration systems for new energy cold chain vehicles. Application Scenarios Food cold chain transportation, medicine constant temperature delivery, RV refrigeration, fresh product long-distance transport.