The Portable Pressure Sensor Calibration System Design

Pressure, especially high pressure with the value more than 100MPa is widely applied in industry. Pressure sensor, which is a device that converts pressure signal into electrical one, must be calibrated to guarantee the results'accuracy and reliability.Traditionally, calibrating pressure sensor through fixing it on the large calibration equipment, which is difficult to meet the calibration demands on test-site. Aiming at this problem, this paper according as the requirements and characteristics of calibration on site, builds a portable calibration system with a strain cylinder pressure sensor as front-end component. Through simultaneously loading the known pressure on standard sensor and another one that need to be measured, compares they input-output curves for calibrate the latter performance.The portable calibration system is mainly composed of standard strain pressure sensor and control system. The standard stain pressure sensor is made since this paper carefully research into design principle and production process of the strain cylinder pressure sensor. Then through testing and evaluating its performance, confirm that it can be seen as a standard device to calibrate the pressure sensor which need to be measured. To achieve the purpose of portable, the control system is battery powered. It adopts ATmega128 and 24-bit high resolution A/D converter-ADS1274 to accomplish signal acquisition and processing, and equips keyboard and LCD screen to monitor calibration process and display real-time calibration results. USB is used for transmitting data between control system and PC. PC can further dispose and analyze the data.Finally, the data error analysis is carried out based on the practical and theoretical point of view, and use significant testing method to evaluate fitting curves. As a result, it is verified that this portable calibration system accords with design demands and can meet the test site calibration requirements.