Temperature Sensors

Temperature sensors come in various forms and types. They are also described in various forms; for example, a temperature sensor is the same as a thermocouple. The temperature sensor/thermocouple consists of two different types of metals joined together at the end.

If the two metals are heated or cooled, a junction occurs, which creates a voltage (4 20ma temperature sensor) that can be transformed to temperature. The thermocouple is a simple, robust, cost-effective temperature sensor used in various temperature measurement processes.

Thermocouple

Thermocouples are manufactured in a wide range of types, each with different features such as their temperature range, used materials and robustness. Each thermocouple, whether it are thermocouple probes, thermocouple probes with connectors, infrared thermocouples, bare wire thermocouples or just thermocouple wire, is defined by a letter. Common types include:

• Type J
• Type K
• Type L
• Type T

The used letter in the thermocouple type refers to the materials used to create the junction. For instance, a type K thermocouple contains chromel and alumel conductors, which can be used for the measurement of tempratures fluctuation from -270°C up to 1372°C. Thermocouples are ideal tools for measuring high temperatures and are a popular choice and are a robust, reliable and affordable solution.

Resistance thermometer

Resistance thermometers also referred to as RTD, differ from thermocouples. Where a thermocouple measures the temperature by using two different metals in the sensor to produce a voltage, a resistance thermometer or RTD use the changes in the electrical resistance of metals to measure the temperature changes. 

GMS Instruments is an official distributor of WIKA and TUVO Instruments various types of resistance thermometer sensor models. Both manufacturers supply RTD’s with connected cables and versions with connection heads.

A temperature transmitter can be installed straight in the connection head. Accuracy classes AA, A and B apply to all resistance thermometers. They are available with a tolerance value to IEC 60751.