A Method for Characterization and Performance Evaluation of Differential Pressure Transducer by Using Twin-Piston Pressure Balance

摘要

Calibration and performance evaluation of a differential pressure transducer is vital for its application in industries, especially those involved with foreign trade. For these industries, a proper universally accepted method is a need for differential pressure metrology. So, a novel method of calibration and characterization for digital differential pressure transducer is studied and carried out for a sample device of differential transducer (Model No. 3K650000137526, Make. ABB), with the use of differential pressure standard in hydraulic mode. The differential pressure transducer is calibrated in a differential pressure range from 0.2 to 2 MPa with maximum static pressure up to 50 MPa, against a twin-pressure balance (Model 55614, Desgranges & Huot, France) available at CSIR-National Physical Laboratory (CSIR-NPL), India. The uncertainty in pressure measurement using twin pressure balance has been estimated, which shows a maximum uncertainty of 3.681E-3 MPa in percentage of readings (coverage factor k = 2). The mentioned calibration method not just only gives the metrological uncertainty but also other performance parameters too. The device under calibration shows a maximum error of 0.42% of reading, average error due to repeatability of 0.12% of reading, maximum error due to reproducibility of 0.21% of reading. It is also found out that the behavior of the digital differential transducer is the same in its positive and negative range span. Finally, a regression equation is developed to predict differential pressure at desired pressure for the system and thus the differential pressure transducer is fully characterized.