How to select the range of a differential pressure transmitter

The key to selecting the range of a differential pressure transmitter is to ensure that the measured pressure range covers the minimum and maximum pressure differences that may occur during operation, while also maintaining measurement accuracy. The following are some factors to consider when selecting the range of a differential pressure transmitter: 1. Maximum measured pressure difference: The range of the differential pressure transmitter should be able to cover the maximum pressure difference that may occur in the process. 2. Normal operating pressure difference: When selecting a transmitter, priority should be given to the pressure difference under normal operating conditions; it is advisable for this pressure difference to fall within the middle range of the transmitter’s scale. 3. Process variations: Take into account the transients and changes that may occur during the manufacturing process, to ensure that the pressure difference remains within the measurable range of the transmitter under all conditions. 4. Accuracy and resolution: When selecting the range, it is necessary to ensure that the measurement accuracy and resolution meet the process requirements. If the range is chosen too large, it may compromise the sensitivity and accuracy of the measurement. 5. Safety margin: A certain safety margin is usually considered to prevent exceeding the range limits in case of fluctuations or shocks in process pressure. For differential pressure level gauges, the selection of the range usually requires consideration of factors such as the maximum possible liquid level difference in the container and the density of the liquid. For differential pressure flowmeters (such as Orifice throttling devices), it is necessary to determine them based on the flow calculation formula and the process parameters of the fluid (such as pipe size, fluid density, flow velocity, etc.). For example, when using a differential pressure flow meter, the following steps are generally followed to select the range: – Determine the designed flow range of the flow meter, including the minimum and maximum flows. - Based on the flow calculation formulas, such as the Orsat equation, the differential pressure values at the corresponding minimum and maximum flows are calculated. - Determine the range of the differential pressure transmitter so that it can cover the maximum differential pressure values, while ensuring that the differential pressure under normal process flow rates falls within the upper middle part of this range, such as 60%-80%, in order to guarantee measurement accuracy. The final choice must take into account various factors such as the performance parameters of the transmitter, pressure loss, cost, and process control requirements. If possible, it is recommended to consult a professional instrument engineer or supplier to determine the optimal range that meets the requirements of a specific application. .

The EJA510E is available in just these 4 versions; depending on your process requirements, you can only choose one from these four options. What about a calibration range of 60%-80% for the instruments – does the manufacturer actually carry out calibration for that as well?