Resistance Temperature Sensors

Resistance thermometer use metals that alter their electric resistance when heated.

Platinum is the most commonly used material for industrial RTD. However Copper and Nickel are also used for some applications.

The resistance at 0°C is called R0 and it is an important parameter to be defined. The most commonly used RTD element is of platinum with resistance of 100 Ω at 0°C. Thus named as Pt 100 Platinum RTD are suitable for temperature range -200 to 850°C. Normally, Industrial RTD’s are used at temperature range upto 400°C.

Temperature Class A (±) Class B (±)
-200°C 0.55°C 1.3°C
-100°C 0.35°C 0.8°C
0°C 0.15°C 0.3°C
100°C 0.35°C 0.8°C
200°C 0.55°C 1.3°C
300°C 0.75°C 1.8°C
400°C 0.95°C 2.3°C
500°C 1.15°C 2.8°C
600°C 1.35°C 3.3°C
700°C - 3.8°C
800°C - 4.3°C
850°C - 4.6°C

Tolerance Table for Type of RTD(as per IEC 751) Pt100RTD Toleranace Table