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Question
Do all thermocouples have a neutral temperature?
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Solution
The temperature of the hot junction at which the thermo-emf in a thermocouple becomes maximum is called neutral temperature for that thermocouple. For a thermocouple in which the constants a and b have the same sign, the neutral temperature will be less than the temperature of the cold junction of the thermocouple \[\left(\text{as }\theta_n = - \frac{a}{b}\right).\]
There will be no neutral or inversion temperature, as the temperature of the hot junction cannot be less than the temperature of the cold junction.
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