1.Working Principle Built-in NTC negative temperature coefficient thermistor: Temperature increases → resistance reduces; Temperature drops → resistance rises. The main board converts resistance data into temperature values to adjust fan speed and trigger high-temperature alarm. 2. General Technical Specifications R25 nominal resistance: 10kΩ / 50kΩ / 100kΩ B value: 3950K, 3990K Temperature accuracy: ±1℃~±2℃ Operating temperature range: -40℃ ~ 200℃ Oil & high temperature resistant, anti-grease corrosion 3. Structure Composition Glass-sealed high-stability NTC chip Small stainless steel/copper metal sensing head High-temperature silicone braided wire, resistant to oil fume aging Fixed plastic bracket for easy installation inside the hood Custom small terminals for circuit board welding 4. Main Functions Intelligent wind speed automatic adjustment When cooking produces high-temperature flue gas, the sensor feeds back high-temperature signals, and the hood automatically increases fan speed to exhaust heavy oil smoke faster. High temperature fire safety protection If abnormal high temperature (caused by open fire, pot burning dry) is detected, the machine will trigger an alarm, automatically turn on the maximum air volume, or even cut off the heating linkage circuit to avoid fire risks. Motor overheat protection Monitor the temperature of the internal fan motor; shut down the motor to prevent burnout when overheated. Timing residual smoke removal Cooperate with temperature signal to judge whether cooking is finished, and automatically delay exhaust to remove residual oil fume. 5. Common Fault Phenomena Fan speed cannot automatically increase when frying food No high-temperature alarm when open fire appears Range hood shuts down randomly during use Temperature sensing failure, intelligent auto mode invalid 6. Application Scope Side suction range hood, top suction cooker hood, integrated stove with hood, commercial kitchen fume exhaust equipment