Mineral insulation thermocouples, commonly referred to as MgO (magnesium oxide) thermocouples, are used in many laboratory processes and applications. They are available in J, K, T, E, N thermocouples and a wide range of different sheath diameters and materials. Their nature is flexible and bendable, and their relatively high temperatures make MI thermocouples suitable for many measurement applications. Temperature makes it a popular option.

The 503 series is a complete set of thermocouples and thermowells because the thermocouples are inside the protective sheath, which means that corrosive fluids do not damage the sensor sheath and if damaged, it is applied to the body of the thermocouple and easily removes the sensor from the head or during repairs. Replace the head and there is no need to empty the tank or furnace. In times when the temperature, pressure and fluid flow are high, frequency weakness calculations must be performed for the thermowell, which is done according to ASME PTC19.3 standard and the dimensions are provided along with the map.