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, beginning with a reference point, which generally 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 additionally that of the span (TCC) should be taken into account individually. The zero-point error describes the result of temperature on the zero signal. Pound of the span specifies the result of temperature on the full scale value. The average person temperature coefficients of zero point and of span are usually specified as magnitudes, and therefore they can be either positive or negative.
If within an individual instrument the zero-point error gets the same sign because the error of the span, both of these 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. Connect to WIKA pressure sensors.

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