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As is well known, a valve positioner is a major accessory for control valves, and it is usually used in conjunction with pneumatic control valves. Based on their structure, they can be classified into: pneumatic valve positioners, electro-pneumatic valve positioners, and intelligent valve positioners. It first receives the output signal from the regulator, and then uses that output signal to control the pneumatic control valve. When the control valve operates, the displacement of the valve stem is fed back to the valve positioner through a mechanical mechanism, and the valve position is transmitted to the higher-level system via electrical signals. Knowing how to use and configure valve positioners correctly can help us achieve better results with less effort, thereby avoiding losses caused by improper settings. Today, the technical editor from Xi’an Pruide will show you how to carry out automatic settings and the relevant precautions. I. Automatic setup and zero-point adjustment by the valve positioner When the valve positioner performs automatic setup and zero-point adjustment, it is necessary to monitor the SVP. If the SVP was not ordered for the specific valve or actuator, and it is being used while pressing the button to activate the valve, then the valve operation must first be set in the SVP before the automatic setup can take place. The opening switch is a two-position switch used to trigger automatic settings and perform manual zero-scale calibration. The operation steps for the valve positioner are as follows: 1. Set the input signal of SAP to 18+1 mADC. 2. Open the front cover of SVP and move the position switch to “UP” (for FloWingRotaryVFR valves, move it to “DOWN”). 3. Keep this position until the valve starts to move (about 3 seconds). This will start the automatic setup program. Release the opening degree switch. 4. The valve is moved from fully closed to fully open, twice in total. Then the valve is opened to about 50% and kept in that position for three minutes. 5. Confirm whether the automatic setup procedure is complete by changing the input signal. The entire automatic setup process takes about three minutes. II. When using a switch for automatic setup of valve positioners, the following points should be noted: During the automatic setup process, do not set the input signal below 4 mA. As long as the signal remains within the 4–20 mA range, changing the input signal during automatic setup will not affect the process. ) Because when automatic setting is enabled, if the input signal is below 4mA, the automatic setting fails and it must be restarted. After the valve positioner has been automatically configured, maintain a signal (power supply) of at least 4 mA for at least thirty seconds to ensure that the data and parameters are stored in the SVP memory. After the operation is complete, the valve’s operation is checked by changing the input signal and verifying whether the valve moves to the correct position corresponding to that signal. If the range position is offset, perform a range adjustment. Proper use and maintenance of valve positioners can help avoid significant losses caused by minor issues that arise during the operation of instruments. I believe that through today’s introduction, everyone has gained some understanding of the basic settings for valve positioners. In the future, I will continue to share more knowledge related to instruments, so feel free to keep learning.