Differences of RTD & thermocouples ?

Question

Accepted Answer

RTDs and thermocouples are both temperature sensors, but they differ in terms of principle, accuracy, range, and cost.

RTD stands for Resistance Temperature Detector, while thermocouple is a temperature sensor based on the Seebeck effect.
RTDs are more accurate and have a higher temperature range compared to thermocouples.
RTDs are more expensive than thermocouples.
RTDs have a linear relationship between resistance and temperature, while thermocouples have a non-linear relationship.
RTDs are typically made of platinum, while thermocouples can be made of various materials like iron, copper, or nickel.
Example: RTDs are commonly used in laboratory and industrial applications where high accuracy is required, while thermocouples are often used in HVAC systems or in situations where cost is a factor.

Accepted Answer

RTD temp.range 200-400c, T/C temp.range 200-1750c

Accuracy: 0.1 to 1C, 0.5 to 5C.

Principle: Change in resistance with respect to temp., See Back effect.

Type: PT100, PT50, PT100. E,J,K,S,N,T.

Responce time: 1 to 50 sec, 0.1 to 10 sec.

Cost: More than T/C, Less than RTD.

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