Differences between Thermistors and Thermocouples

Both thermistors and thermocouples are viable options for temperature measurement and control. Both resistance sensors serve the same function but work differently. Picking between the two should depend on the needs of the user and the application they are seeking to complete. Below, we will highlight some of the general differences between the two types of sensors.

A thermocouple has two main wires (each being made of dissimilar metals) that are welded into a junction. They are used because they can handle extreme temperatures. Versions that are built with precious metal junctions can withstand heats as high as 3272°F/1800°C. In many cases, construction of a thermocouple system will cost more than a thermistor while providing less sensitivity and stability.

Thermistors use metal oxides beads that are encapsulated in either epoxy or glass. Typically, a thermistor will show large NTC (negative temperature coefficient). Depending on construction, thermistor prices and performances vary, but the device does come with standard benefits. Thermistors are highly sensitive and can be made small (to the size of a pin) for sensing in small spaces. A basic thermistor is relatively inexpensive.

We know that deciding between temperature sensing equipment is vital for companies to stay in business. Making wrong choices about sensing tools can be detrimental to performance. Let us help you get the right resistive temperature devices.