Resistance temperature devices (RTDs)

Updated July 9, 2011

Click here to go to our main page on heat

Click here to go to our main page of temperature measurement

RTDs are similar to thermistors, but they generally cost more and are more accurate. That's because RTDs are made from thin films of elemental metals, such as platinum. Because platinum has very low bulk resistivity, you need to create a thin film with a lot of squares to obtain a useful total resistance.

The temperature coefficient of resistance (TCR) of platinum RTDs is around 0.0038 ohms/ohms/°C.