Temperature coefficients (TC) of pressure sensors

Since temperature affects the measuring accuracy of a pressure sensor, there always remains a small temperature error in the rated temperature range despite an array of compensation measures. This error is frequently expressed in the data sheets of manufacturers of pressure sensors as temperature coefficient (abbr. TC). This coefficient describes a (linear) error, starting from a reference point, which in most cases is room temperature.
Accordingly, the temperature error at room temperature is zero and increases with increasing difference of the temperature from room temperature with the specified coefficient in linear fashion (see figure). Basically, not merely the zero-point temperature coefficient (abbr. TC0), but additionally that of the span (TCC) should be considered individually. The zero-point error describes the result of temperature on the zero signal. The error of the span specifies the result of temperature on the full scale value. Fine of zero point and of span are usually specified as magnitudes, meaning that they are often either positive or negative.
If in an individual instrument the zero-point error has the same sign because the error of the span, these two temperature errors may add up in worst case. An average value for the common zero-point temperature coefficient of a pressure sensor is: 0.2 % / 10 K. Link to WIKA pressure sensors.

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