Description:- Extension leads of different metals but having similar EMF output between 0°c to 100°c connected between Thermocouple metals junction and the measuring instruments are called compensating cables which are generally recommended as solid conductor leads.
Application:- Different metal pairs generate different EMFs which is proportionate to the hot junction and the point where it is measured. Common combination of thermocouple metals.
- K-Chromel/AIumel-Most commonly used.
- T-Copper /Constantan- for low temperature & cryogenic applications.
- J-Iron/ Constantan-Used in reducing atmosphere
- E -Chromel/ Constantan-Highest EMF output.
- R-(Platinum-13% Rhodium)/ Platinum & S-(Platinum-10% Rhodium) / Platinum-very High temperature measurements.
- B- (Platinum-30% Rhodium)/ Platinum mainly used in glass industry.
- Different color codes of cores and sheathing as per international practices are used to denote the various thermocouple cables.