Various types of thermocouples are present in multiple calibrations and combinations of metals. The most popular and usual thermocouples are the “Base metal” thermocouples introduced as types K, J, T, E and N. The others are high-temperature forms defined as Noble metal thermocouples, including Types S, R, C and B. Let’s understand what is thermocouples first in this post and then explore their various types.
What is a Thermocouple?
A thermocouple is a temperature sensor which is used for detecting the temperature. It consists of two dissimilar metal wide legs, and these wire parts are joined at the end of the system to create a junction. When the junction of the two metals is heated, the voltage is produced, which is correlated back to the temperature.
Thermocouples are primarily used in particular scientific and OEM applications, as well as in some industrial technologies. Industrial applications usually include power generation, gas or oil production, pharmaceuticals, cement production, biotech, and paper & soft tissue production. This instrument is also used in household appliances such as stoves, toasters, and heaters. The advantages of thermocouples are quite appealing due to their properties like high-temperature toleration, low price, and a wide range of types.
Different Types of Noble Metal Thermocouples
The noble metal thermocouples use Platinum or platinum and rhodium alloys for each conductor. These are considered the most stable thermocouples but have lower sensitivity.
Types B, R and S are the types that are usually used for high-temperature measurements due to their high cost and low sensitivity.
- B Type Thermocouple
These types of thermocouples are extremely utilized in high-temperature measurements and have a high state of precision. This product features Platinum with 30% rhodium for the positive leg and Platinum with 6% rhodium for the negative leg. The temperature range is from 1370 to 1700°C. The accuracy is +/- 0.5% or +/- 0.25%, with a particular error limit of +/- 0.25%. Its sensitivity is 5 to 10 µV/°C.
- R Type Thermocouple
This type of noble metal thermocouple includes a high percentage of rhodium, close to 50%, then the S-type, which makes it more expensive. It can be employed in low-temperature measurements according to its precision and reliability. The temperature range of these thermocouples is 870 to 1450 °C.
- S Type Thermocouple
The S-type is employed especially in high-temperature applications, including pharmaceutical and biotech industries. Nevertheless, it is used occasionally in low- temperature applications according to its stability and high accuracy. It has Platinum with 10% Rhodium as positive and pure Platinum as the negative leg. Its temperature range is 980-1450 °C.
If you are exploring various types of thermocouples for a specific function in your industry, Tempsens have a wide range to offer you. We include various types to meet the specialized necessities and are manufactured with the finest quality. Take a look at our catalog once!
