The Most Common Types of Temperature Sensors

Thermocouple
Working principle: Produces voltage from temperature difference between two metal joints.
Features: Wide temperature range, low cost, durable, moderate precision.
Usage: Industrial high-temperature detection, furnace, engine.

RTD (Resistance Temperature Detector)
Working principle: Metal resistance changes steadily with temperature.
Features: High accuracy, stable performance, good repeatability.
Usage: Precision industrial measurement, refrigeration, pipeline.

Thermistor
Working principle: Sharp resistance variation with tiny temperature change.
Features: High sensitivity, small size, low price, narrow measuring range.
Usage: Household appliances, battery, wearable device.

Semiconductor Temperature Sensor
Working principle: Chip electrical characteristics change with heat.
Features: Digital output, easy circuit matching, simple use.
Usage: Mobile phone, computer, car electronic system.

Infrared Temperature Sensor
Working principle: Detect infrared radiation emitted by objects.
Features: Non-contact measurement, fast response, no surface damage.
Usage: Forehead thermometer, industrial temperature scanning.

Bimetallic Strip
Working principle: Two metals expand differently to bend with heat.
Features: Simple structure, no power supply, switch control.
Usage: Water heater, oven, overheat protection switch.