Thermocouples are two wires of dissimilar metals, joined at one end. Changes in the temperature at the “hot junction” (measuring end) induce a change in electromotive force (EMF) at the “cold junction,” where it can be input into a controller or indicator. As the temperature increases, the output EMF also rises, though not completely linearly. Thermocouples can inexpensively measure temperatures over wide ranges. They are very rugged but are somewhat less accurate than resistance temperature detectors (RTDs) and thermistors. United Electric Controls (UE) offers type J, K, E, and T thermocouple terminal head styles as well as beaded thermocouple types: K, R, S, and B.
See product types below for more information or contact us directly at 617.923.6966.
There are many different types of thermocouples. They are made of different types of wire and have very different properties, making one type better for a specific application than another. Below are descriptions of the types of thermocouples made by UE.
Type J
The Iron – Constantan J curve thermocouple is the most widely used thermocouple. It is versatile and relatively low cost. The Type J thermocouple has a positive iron wire and a negative Constantan wire and is recommended for reducing atmospheres. The operating range for this alloy combination is from 0° C to 750° C (32° F to 1380° F) for the largest wire sizes. Smaller size wire should operate in correspondingly lower temperatures.