Table of Contents
Which one you prefer
In the industry temperature plays a major role, and for this there is two commonly use sensors dominate the field:
RTD ( Resistance Temperature Detectors) and Thermocouple. But which one is best for the application?
Below is the comparison:
RTD
As the name suggests Resistance temperature detector, which means the temperature is measured with respect to the resistance associated with the sensor, this type of sensor is calibrated as per the material used for it, so a table is made for the particular resistance and temperature, for this an external transmitter is used which convert the non electric signal to electric signal, so it can be transferred to the controller.

- This is more stable type of sensor
- Accuracy is very high ( +- 0.1 to +- 0.5 °c)
- This is ideal for precise, low to moderate temperature application ( – 200°c to 850°c)
- Expensive but this is reliable
Thermocouple
A thermocouple is a type of thermoelectric device, which is continuously use to measure the changes in the temperature with the help of sensor connected to it. Normally thermocouple is joined with the two different metal which create the small voltage difference with respect to the temperature. The total output voltage depends upon the temperature difference between two different metals. To measure the temperature we must have to know the reference voltage which we have to keep at the one side, which is know as cold side.

- Wider temperature range ( -200 to – 2300°c)
- Response time is faster
- This is durable and cost effective
- Preffered for Robost Environment and Harsh conditions