QJ 28-1987 in English

Calculation method for static accuracy of pressure sensors

This standard is applicable to the calculation method for static accuracy of pressure sensors during calibration, which are developed, produced and used by the Ministry of Aerospace Industry of the People's Republic of China.

The environmental conditions for static calibration of sensors shall be specified in the verification regulations formulated by the metrological department based on the type and accuracy class, etc. of the sensor under calibration.

The comprehensive error of calibration system (usually including standard pressure source, power supply and sensor output measuring instrument) shall be generally 1/5~1/10 of and shall not be greater than 1/3 of the basic tolerance of the sensor under calibration.

It is temporarily allowed to calibrate sensors in class of 0.05 with calibration equipment in accuracy of 0.02% under present conditions.

When a sensor is calibrated, the number of pressure calibration points K, including zero point, shall not be less than 6, and the number of calibration cycles R shall not be less than 3. The number of calibration points and calibration cycles depends on the accuracy and use requirements of the sensor under calibration, usually with K=6~11 and R=3~5. A total of 2RK calibration data can be obtained from each calibration.

For calibrated sensors, characteristic equation, linearity, hysteresis, repeatability and accuracy values shall be provided.

1 Calibration curve of the sensor

Let X be the sensor input (pressure) and Y be the sensor output (calibration data).

Contents
1 Calibration curve of the sensor
2 Working straight line of sensor
3 Basic static performance indexes of sensors
4 Accuracy of sensor, A
Annex A (Supplement) BASIC program applicable to pocket computers such as PC-1211