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In previous articles, we covered how to zero and set the range of Rosemount transmitters, as well as their installation methods and usage precautions. In those previous steps, it was also necessary to take into account the transmitter’s sensitivity and frequency response characteristics. So, what is the linear range of a Rosemount transmitter? The linear range of a Rosemount transmitter refers to the range in which the output is proportional to the input. Theoretically, the wider the linear range of a Rosemount transmitter, the larger its measurement range, and it can ensure a certain level of measurement accuracy. Moreover, within this range, the sensitivity of the Rosemount transmitter remains constant. The linear adjustment of Rosemount transmitters is mainly carried out after the zero and range settings of the Rosemount transmitters have been adjusted. At this point, it is necessary to check the linearity of the Rosemount transmitter. Generally, the linearity of a Rosemount transmitter is adjusted during its factory calibration, and usually no adjustment is required on-site. However, if a range adjustment is required when the Rosemount transmitter is in use on-site, or if high linearity within a specific range is needed, the linearity can be adjusted using the method described below. When adjusting the linearity, it is necessary to open the cover on the other side of the Rosemount transmitter body; there the linear adjustment screw of the Rosemount oscilloscope can be found. At this point, it is important to check the rubber gaskets – if they are damaged or severely worn, they should be replaced. For nuclear-grade Rosemount transmitters, nuclear-grade gaskets must be used after calibration. Apply a pressure at the intermediate range to the Rosemount transmitter, and record the error ΔX between the theoretical output signal of the Rosemount transmitter and its actual output signal; then apply the full-scale pressure for that selected range. Adjust the linear potentiometer so that the output of the Rosemount transmitter is increased by the following amount from its original value: (ΔX)*6*(maximum range/adjusted range). When the actual output signal of the Rosemount transmitter is lower than the theoretical output signal, increase it ； When the actual output signal of the Rosemount transmitter is > the theoretical output signal, reduce it. Then, it is necessary to readjust the range and zero point of the Rosemount transmitter.