To provide an evaluation unit for differential pressure sensor producing an output signal corresponding to a pressure difference corrected for rated pressure error.
Inner temperature Ti corresponds to the sum of reciprocal-of capacitances C1, C2 and it is equal to the sensor temperature Ts when the static pressure being applied to two diaphragms 3a, 3b is zero and the difference between first and second pressures p1, p2 is zero except the temperature difference T0. A measure for the static pressure ps at a reference temperature TR, i.e., a first correction value ΔK, is then calculated according to a formula; ΔK=Ti-Ts-To. A pressure difference Δp corrected for a measurement error caused by the static pressure ps using the first correction value ΔK is then calculated from the measurement of pressure difference ΔPM.
BANHOLZER KARLHEINZ (DE)
FLOEGEL KARL (DE)
JUNG PETER (DE)