Abstract：By analyzing and studying the performance of the 2500Pa micro-pressure reference after modification, the relationship between working medium temperature and the liquid level height of the container was summarized, the relationship was extracted, and the liquid level height/temperature coefficient at the pressure point 0 was obtained:a=0.030mm/℃; b=0.017mm/℃; Using the modified formula to optimize the water density value method, the accuracy of the water density value was improved by 0.0006% on average, and the errors in the density table of relevant regulations were corrected. The comparison experiment En<1, Obtain satisfactory results. Through the above optimization, the performance of the micro-pressure benchmark can be improved to meet the demand of traceability and transmission of pressure value in the development of the times.
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