With WIKA, temperature sensors in industrial temperature measurement are essentially divided between the following groups:
Thermocouples consist of two different metals which are bound together to form the 'thermocouple'. The connection point (hot junction) represents the actual measuring point of the temperature sensor, the wire ends are designated as the cold junction. When there is a temperature change at the measuring point of the temperature sensor, due to the different electron densities of the metals and the temperature difference, a voltage is generated between the hot and cold junctions. This is approximately proportional to the temperature of the measuring point (Seebeck effect).
The low diameter of the sheathed thermocouple of a temperature sensor enables a response time that is faster than is possible with a resistance thermometer.
Surface thermometers feature problem-free installation without thermowells. The mounting to vessels is achieved using a welded-on or screwed-on contact block which contains the temperature probe. For fixing to pipelines, a variant with tightening strap is suitable. Centrally bored washers and metallic weld-pads are available as further process connections. For specific ambient conditions, the connection leads of the surface thermometers can be delivered with special insulation materials. The cable end can be delivered ready for connection or with fitted plug (optional) or with a field case.