From RS PRO a Type K thermocouple temperature sensor designed for taking surface temperature measurements. The thermocouple lead is made from twin-twist wire with a durable PFA insulation. One end of the lead is terminated with a miniature plug for a quick and easy connection. The other end of the wire is terminated with a self-adhesive moulded silicone patch for attaching to a surface.

from different metals joined together at their two ends to form two junctions. The hot, or measuring junction is connected to the body whose temperature is going to be measured. The cold junction or reference junction is connected to a body of known temperature. When the measuring junction is placed on something hot a voltage or potential difference between this and the reference junction occurs. This voltage can then be converted into a temperature measurement using thermocouple reference tables. This process is also known as the Seebeck Effect.

This thermocouple is designed for measuring the temperature on a surface. Most thermocouples have a sensing tip where there ends of the thermocouple wires are encased in sheaths or protection tubes which do not allow for measuring the temperature of a surface area. In surface temperature sensing thermocouples the exposed welded wire junction is housed in a magnet or adhesive patch which provides a true surface contact. This affixing method allows these thermocouples to be used on many types of surfaces including uneven and circular surfaces. They are also simple to use and easy to replace and position.