What is a RTD and thermocouple

Question

Accepted Answer

RTD stands for Resistance Temperature Detector and thermocouple is a temperature sensor made of two different metals.

RTD measures temperature by detecting changes in electrical resistance of a metal wire as temperature changes.
Thermocouple measures temperature by detecting changes in voltage as temperature changes.
RTD is more accurate and stable than thermocouple.
Thermocouple is cheaper and can measure a wider range of temperatures than RTD.
RTD is commonly used in industries such as food and beverage, pharmaceuticals, and HVAC.
Thermocouple is commonly used in industries such as automotive, aerospace, and metalworking.

Accepted Answer

RTDs (Resistance Temperature Detectors) and thermocouples are both temperature measurement devices used in industrial applications, but they differ in how they work and their performance characteristics: 
 
How they work: RTDs are sensors that change resistance as their temperature changes. Thermocouples are made of two different conductors that produce a voltage based on the temperature difference between the two ends. 
 
Temperature range: Thermocouples can measure temperatures from -250°C to +1800°C, while RTDs can measure temperatures from -200°C to +850°C. 
 
Accuracy: RTDs are generally more accurate than thermocouples. 
 
Response time: Thermocouples have a faster response time than RTDs. 
 
Stability: RTDs can maintain stability for many years, while thermocouples can drift in shorter periods. 
 
Applications: Thermocouples are better for high-temperature and high-vibration processes, applications that require fast response times, and those with limited space.

Accepted Answer

RTD is for low Temperature

Thermocouple is used for measuring higher Temperature

RTD output is ohm’s

Thermocouple output is Mili volt

What is a RTD and thermocouple

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