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With the advancement of instrumentation technology, differential pressure transmitters are evolving toward higher precision and greater intelligence. However, technological advancements have led designers into a misconception: when choosing transmitters, people tend to focus on their precision alone, while ignoring other factors that affect measurement accuracy. So, what factors can affect differential pressure transmitters? 1. Influence of range ratio: The range ratio of a differential pressure transmitter refers to the ratio of the maximum value to the minimum value that can be measured by the transmitter while still meeting the accuracy requirements. Generally, the larger the range ratio, the lower the measurement accuracy. A pressure transmitter with a large range ratio has many advantages, as it can be used in various different applications after being calibrated. However, in practice, setting the range ratio too high can lead to many problems with measurement stability. 2. Effect of temperature: In process applications, the process temperature and ambient temperature can vary significantly, and these will certainly differ from the conditions under which the transmitter was tested. This means that its performance will also differ from the reference accuracy specified. The effect of temperature on differential pressure transmitters is minimal when the range is large (i.e., a low range ratio), but it becomes significant when the range is small (i.e., a high range ratio), sometimes even beyond our expectations. 3. Influence of static pressure: Similar to the effects of temperature and range, static pressure also has a significant impact on the accuracy of the transmitter’s zero point and range. In the case of capacitive differential pressure transmitters, such transmitters are almost always affected by static pressure during the operation of production process systems. When the static pressure under operating conditions exceeds a certain value, the error caused by this static pressure can exceed the precision of the transmitter itself. When calculating the precision of the measurement channel, if the error resulting from static pressure is taken into account, it may not be possible to meet the required precision standards. Therefore, it is necessary to correct for the effect of static pressure when calibrating capacitive differential pressure transmitters. 4. Influence of installation inclination angle on the transmitter: The installation inclination angle refers to the angle between the transmitter’s central axis and the vertical line after it is installed in the field. During differential pressure measurement, the sensing element detects the pressure difference between the two sides by measuring the deformation displacement of the center diaphragm. 5. Influence of the height difference between the measurement point and the installation point: Due to the overall design requirements of industrial sites, differential pressure transmitters are often not installed near the measurement point where the readings are taken; instead, pressure is transmitted to a centralized location through pressure transfer pipes, to facilitate maintenance and management. This results in a height difference between the measurement point and the installation point. The pressure medium in the pressure transfer pipes experiences additional pressure due to this height difference, which in turn causes errors. In process industry applications, since the density of the medium is often high, even a small height difference results in significant additional errors. When choosing a differential pressure transmitter, only by paying attention to the factors that affect its accuracy can we make better use of it. For more information on instruments and meters, please follow us~