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Debugging steps: 1. Adjustment – Automatic setting is a unique program that can be used to automatically make various adjustments to the locator. Automatic setting is carried out using the opening switch; when performing automatic setting and zero-to-range adjustment, it is necessary to monitor the positioner. The opening button is used to initiate automatic setting and perform manual zero-to-range calibration. Steps: (1) Set the input signal of the locator to DC 18±1mA ； (2) Open the front cover of the SCP and press the opening button to the “UP” position (“DOWN” for Flowing Rotary VFR valves) ； (3) Hold this button until the valve starts to move (about 3 seconds); this will initiate the automatic setting procedure. Then release this button. (4) The valve will move back and forth from fully closed to fully open twice. After that, the valve was opened to 50% and held there for 3 minutes ； (5) Confirm that the automatic setting procedure is complete by changing the input signal. The entire automatic setup process takes about 3 minutes ； Note: During the automatic setting process, do not set the input model to below 4mA. (As long as the signal is within the 4-20mA range, changing the input signal during automatic setting will not affect the execution of the program.) ) If the input signal drops below 4mA, the automatic setting will become invalid, and it must be restarted. After automatic setting is completed, the signal remains at a level of at least 4 mA for at least 30 seconds to ensure that the data and parameters are saved in the SVP memory. After the operation is completed, check the valve’s operation by changing the input signal to confirm whether the valve moves to the correct position corresponding to the signal. If the full-scale position is offset, perform full-scale adjustment again. 2. Zero-to-range adjustment: Once automatically set, the locator calibrates itself to the fully closed (zero) and fully open (range) positions of the valve. If the valve cannot establish the correct relationship between its opening degree and the controller signal, manually adjust the zero-point and range following the steps below. Note: The position switch will only function when the close and full-open input signals (e.g., 4-20) are the same as those stored in the locator, or as those set in the factory for the close and full-open inputs of the locator. (1) Steps to adjust the valve to the closed position (zero point): a. Send an electrical signal corresponding to the fully closed position of the valve from the controller (e.g., 4mA) ； b. Adjust the valve to its fully closed position by pressing the opening buttons “UP” or “DOWN”. The default value for the forced shutdown feature is set at 0.5%. (2) Steps to adjust the valve to the fully open position (full scale): a. Send an electrical signal corresponding to the fully closed position of the valve from the controller (e.g., 20mA) ； b. Adjust the valve to its fully closed position by pressing the opening buttons “UP” or “DOWN”. Until the valve position is adjusted to the correct place. Note: After completing the zero-to-range adjustment, change the input signal to confirm whether the valve is operating correctly. 3. Maintenance (1) Filter replacement and throttle nozzle repair – It is possible to remove the instrument air contaminants that have accumulated in the locator’s throttle nozzle during this maintenance process. Steps: 1) Cut off the air supply to the locator ； 2) Unscrew the fixing screw from the label area of the A/M switch (Note: When unscrewing the screw, be careful not to lose the A/M switch cover washer and the lock washer) ； 3) Switch from A/M to MAN (manual) mode ； 4) Use forceps or other tools to remove the clamp and take out the old filter screen ； 5) Use wire (with a diameter of 0.3 μm) to remove contaminants from the throttle nozzle (be careful not to allow oil or grease to contaminate the throttle nozzle while removing contaminants) ； 6) Wrap the new filter screen around the A/M switch and press it into place with a clamp ； 7) Turn the A/M switch all the way down ； 8) Fix the nameplate of the A/M switch section to the A/M switch cover plate using set screws. (2) Clean the baffle: If contaminants in the instrument air accumulate on the baffle (Note: Applying pressure to the positioner will change the back pressure of the baffle and nozzle, causing a sudden change in the valve position), 1) Remove the cover ； 2) Unscrew the four screws on the cover plate ； 3) Slide the cover plate to the left, then remove it ； 4) Prepare paper sheets with a thickness of 0.2 mm; ordinary business cards will suffice ； 5) Use a piece of paper to clean the dirt from the gap between the EPM nozzle and the baffle ； 6) After cleaning the gap, reinstall the cover plate and the lid. 4. Troubleshooting (1) The locator does not function (no output air pressure). a. Verify that the rotation angle of the locator’s feedback rod does not exceed 20°. If this angle is exceeded, add an extension rod to the feedback rod to obtain a sufficient feedback length ； b. Check for leaks in the gas supply ； c. Check the electrical input signal ； d. Check whether the automatic/manual switch is in the automatic position ； e. Check the cleanliness of the baffle and filter screen. (2) It is not possible to achieve the full travel distance, or the speed is reduced. a. Check whether the adjustments for the zero point (full open) and the range (full open) are correct ； b. Check the cleanliness of the filter screen and baffle. (3) Misadjustment or overtravel a. Check the allowable rotation angle of the feedback rod.