| 摘要 |
FIELD: physics. ^ SUBSTANCE: preliminary assembly of the sensor is carried out taking into account air-tightness of the inner cavity for relative pressure sensors. The sensor is put into a socket piece with nominal value of tightening torque and the bridge circuit is balanced within 0.5% of the nominal output signal of the sensor. The initial offset values of the sensor U0, U+Çèot and U-Çèot are determined at nominal temperature T0 and boundary temperature values, respectively. The temperature coefficient of resistance (TCR) of the bridge circuit is calculated for boundary temperature values. The arm for connecting the temperature-independent resistor Rs, designed for compensating for nonlinearity of the temperature characteristic of the initial offset of the sensor, is determined from the sign and ratio of nominal values of TCR. A process temperature-independent resistor Rst, whose nominal value must not be less than 6 Ri (nominal value of the arm of the bridge circuit to which the temperature-independent resistor Rs is connected in parallel) is connected in the selected arm of the bridge circuit in parallel to the working tensoresistor. The bridge circuit is balanced without changing TCR of the balanced arm. The offset values of the bridge circuit of the sensor U0s, U+Çè0st and U-Çè0st are determined. The nominal value of the temperature-independent resistor Rs is calculated and the resistor is connected into the measurement circuit together with the resistor Rst, with subsequent intermediate balancing of the bridge circuit without changing TCR of the balanced arm. Additive temperature error is compensated for using a temperature-resistant resistor R. ^ EFFECT: high adjustment accuracy. |
