Linearization of Thermocouple Voltages
Gerald Conrad · Review of Scientific Instruments · 1968
A Wheatstone bridge, with a thermocouple as the source of bridge voltage, and a temperature-dependent arm, can have a voltage output which contains a square term in the temperature. If this output is connected in series with that of another thermocouple, the combined voltages may be more or less linear than that of the thermocouple alone, depending on the temperature range, and the polarity of the series connection. In particular, in the range extending 50° each side of 0°C, good linearity may be obtained. This may have some value for obtaining realtime readout of temperatures for meteorological purposes.