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When using Rosemount differential pressure transmitters, we sometimes encounter issues with static pressure errors. When faced with such problems, many of our instrument operators become flustered and don’t know how to address them. Below, the technical editor from Shaanxi HuiBo Electromechanical will summarize for you the reasons behind static pressure errors in Rosemount differential pressure transmitters, as well as the methods to correct them. I. Causes of the static pressure error in Rosemount differential pressure transmitters: 1. The main reason for this phenomenon is that the effective areas of the diaphragm chambers for positive and negative pressures are different, which results in a resultant force on the diaphragm that is not equal to zero. Under such circumstances, it is easy for the position of the main rod to shift, resulting ultimately in zero-point drift. 2. Rosemount differential pressure transmitters generally have their differential pressure calibration performed with the vacuum chamber exposed to atmospheric pressure. However, during on-site operation, when performing an actual static pressure zero calibration of the transmitter, there is a discrepancy between the zero output value obtained during calibration with the chamber open to the atmosphere and the zero output value at that moment, which results in a static pressure error. II. Correct method for correcting the static pressure error in Rosemount differential pressure transmitters: If a static pressure error occurs in a differential pressure transmitter and is not corrected in a timely manner, it will cause errors in the overall measurement results. Next, we will introduce the correct method for correcting hydrostatic error. 1. For the three-valve assembly of the transmitter, one of the high-pressure and low-pressure valves should be opened while the other is closed, with the balance valve kept in the open position. 2. When it is uncertain whether the positive or negative pressure chamber is filled with the medium to be tested, this issue can be resolved by venting air or removing gas from the chamber. 3. The same static pressure is simultaneously introduced into the positive and negative chambers of the pressure transmitter. That is all for what we are going to discuss today: “The reasons for static pressure errors in Rosemount differential pressure transmitters and the methods to correct them”. It is hoped that through today’s learning, our field instrument operators will be able to correctly address such issues with ease in the future.