What are the types of temperature detection sensor elements?

Temperature detection sensor elements are devices used to measure temperature and are widely used in industry, medical treatment, scientific research and other fields. This article will introduce in detail the types, working principles, performance characteristics and application fields of temperature detection sensor elements.

1. Types of temperature detection sensor elements

Temperature detection sensor elements are mainly divided into the following categories:

1.1 Thermocouple Sensor

A thermocouple sensor is a sensor that converts temperature changes into voltage signals. It consists of two conductors of different metal or alloy materials, welded together at both ends. When one end of the thermocouple is heated, a thermoelectric potential difference is generated between the two materials, which generates a voltage signal. Thermocouple sensors have the advantages of wide measurement range, high accuracy, and fast response speed.

1.2 Thermal resistance sensor

A thermal resistor sensor is a sensor that converts temperature changes into resistance changes. It is usually made of metal materials (such as platinum, copper, nickel, etc.) and has high accuracy and stability. The working principle of the thermal resistor sensor is that when the temperature changes, the resistance value of the material will change. By measuring the change in resistance value, the temperature value can be calculated.

1.3 Semiconductor Sensors

A semiconductor sensor is a sensor that measures temperature by using the property that the resistance of semiconductor materials changes with temperature. Semiconductor sensors have the advantages of small size, light weight, high sensitivity, and fast response speed. Common semiconductor sensors are of two types: NTC (negative temperature coefficient) and PTC (positive temperature coefficient).

1.4 Infrared Sensor

Infrared sensor is a sensor that uses infrared energy radiated by an object to measure temperature. It does not need to contact the object being measured and has the advantages of non-contact, non-destructive, and fast measurement. Infrared sensors are widely used in industry, medical treatment, scientific research and other fields.

1.5 Fiber Optic Sensors

Fiber optic sensor is a sensor that uses the characteristics of optical fiber to transmit light signals to measure temperature. It has the advantages of anti-electromagnetic interference, high temperature resistance, and corrosion resistance. Fiber optic sensors are widely used in petroleum, chemical, electric power and other fields.

1.6 Capacitive Sensors

Capacitive sensor is a sensor that measures temperature by using the property that the capacitance of a capacitor changes with temperature. It has the advantages of wide measurement range, high accuracy and good stability.

1.7 Pressure Sensor

A pressure sensor is a sensor that uses pressure changes to measure temperature. It is usually made of metal or ceramic materials and has high accuracy and stability.

1.8 Acoustic Sensor

An acoustic wave sensor is a sensor that measures temperature by using the property that the propagation speed of acoustic waves in a medium changes with temperature. It has the advantages of non-contact, non-destructive, and fast measurement.

1. Working principle of temperature detection sensor element

2.1 Working Principle of Thermocouple Sensor

The working principle of thermocouple sensors is based on the Seebeck effect. When two conductors of different metal or alloy materials are welded together, if the temperatures at both ends are different, a thermoelectric potential difference will be generated between the two materials. By measuring the thermoelectric potential difference, the temperature value can be calculated.

2.2 Working Principle of Thermal Resistance Sensor

The working principle of the thermal resistor sensor is based on the property that resistance changes with temperature. When the temperature changes, the resistance value of the material will change. By measuring the change in resistance value, the temperature value can be calculated.

2.3 Working Principle of Semiconductor Sensors

The working principle of semiconductor sensors is based on the property that the resistance of semiconductor materials changes with temperature. When the temperature changes, the resistance value of the semiconductor material will change. By measuring the change in resistance value, the temperature value can be calculated.

2.4 Working Principle of Infrared Sensor

The working principle of infrared sensors is based on the relationship between the infrared energy radiated by an object and its temperature. When the temperature of an object changes, the infrared energy it radiates will also change. By measuring the change in infrared energy, the temperature value can be calculated.

2.5 Working Principle of Fiber Optic Sensor

The working principle of fiber optic sensors is based on the transmission characteristics of light in optical fibers. When the temperature changes, the transmission characteristics of light in optical fibers will change. By measuring the changes in the light transmission characteristics, the temperature value can be calculated.

2.6 Working Principle of Capacitive Sensor

The working principle of capacitive sensors is based on the characteristic that the capacitance of a capacitor changes with temperature. When the temperature changes, the capacitance of the capacitor changes. By measuring the change in capacitance, the temperature value can be calculated.

2.7 Working Principle of Pressure Sensor

The working principle of pressure sensors is based on the relationship between pressure changes and temperature. When the temperature changes, the volume of the object changes, which causes a change in pressure. By measuring the change in pressure, the temperature value can be calculated.

2.8 Working Principle of Acoustic Wave Sensor

The working principle of the acoustic wave sensor is based on the characteristic that the propagation speed of the acoustic wave in the medium changes with the temperature. When the temperature changes, the propagation speed of the acoustic wave in the medium will also change. By measuring the change in the propagation speed of the acoustic wave, the temperature value can be calculated.

1. Performance characteristics of temperature detection sensor elements

3.1 Performance characteristics of thermocouple sensors

Thermocouple sensors have the advantages of wide measurement range, high accuracy, fast response speed, simple structure and low cost. However, the output signal of thermocouple sensors is small and needs to be amplified.

3.2 Performance characteristics of thermal resistance sensors

Thermal resistance sensors have the advantages of high precision, good stability, and strong anti-interference ability. However, the measurement range of thermal resistance sensors is relatively narrow and requires linearization.