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 a variety of compensation measures. Undeniable is often expressed in the info 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 only the zero-point temperature coefficient (abbr. TC0), but also that of the span (TCC) should be taken into account individually. The zero-point error describes the effect of temperature on the zero signal. The error of the span specifies the effect of temperature on the entire scale value. The average person temperature coefficients of zero point and of span are usually specified as magnitudes, meaning that they can be either positive or negative.
If in an individual instrument the zero-point error has the same sign because the error of the span, both of these temperature errors may accumulate in worst case. An average value for the average zero-point temperature coefficient of a pressure sensor is: 0.2 % / 10 K. Link to WIKA pressure sensors.

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