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01 Installation and calibration of the valve positioner: The valve positioner SVP is designed to withstand harsh operating conditions. However, the installation location must meet certain standards; otherwise, unintended operations may occur. Valve positioners are designed to operate under the following conditions: ■ Ambient temperature of -40°C to +80°C, with relative humidity of 10% to 90%. ■ No sudden changes in temperature or humidity, and the magnetic field strength must not exceed 400 A/m. ■Avoid installing the grid SVP near equipment such as large transformers and high-frequency electric furnaces. ■For HA actuators, the vibration shall not exceed 2G (5–400 Hz). The valve positioners are carefully designed to be used in combination with direct-acting actuators, reverse-acting actuators, or rotary actuators to control valves. The weight of the SVP host is approximately 1.7 kg. The SVP should be connected in the same way as traditional electrical valve positioners. The type and size of the valve positioner actuator determine the type of mounting plate as well as the SVP settings. If you order an SVP with a specified type of actuator, the SVP should come with the correct installation kit, and the appropriate actuator settings should be programmed into the SVP. Then, an automatic setup program is used to calibrate the SVP. Please note that incorrect settings not only reduce the effectiveness of SVP but may also cause it to be damaged or malfunction. To remove the SVP from an existing valve, first disconnect any control lines that supply pneumatic power or those that block the control signals to the valve actuator. When the SVP is installed in a hazardous environment (such as corrosive air), it is not recommended to turn off the air supply unless the SVP is removed. Air pressure can prevent corrosive gases from entering the SVP. 02 Valve positioner: Before installing the SVP, please check: Change: Use the appropriate installation version and feedback rod length that match the actuator. Clearance: Do not install the SVP in locations where maintenance is difficult, as this may interfere with pipes, wiring, or adjustments. Check for mechanical interference and valve operating clearance. Orientation: Install the SVP in the correct direction. Avoid having the left side of the SVP (where the pilot relay is located) at the top. Vulnerability: SVP may be damaged by excessive impact or pressure. Do not press the feedback rod or the domed feedback plug. Stability: Please ensure that the bolts and nuts are firmly tightened onto the SVP and control valves. In practical applications, compared to other instruments, valve positioners are devices with a relatively low failure rate. We organized personnel to repair damaged valve positioners, and those involved came to the conclusion: how could valve positioners get damaged? Summary of the causes of the fault: spring deformation, dirty amplifier, clogs, dirty nozzle baffles, dirty constant-throttle orifices, etc. Most of these issues are caused by external factors, primarily the air supply; therefore, what we do is to clean the filters regularly. The proper installation and calibration of valve positioners are very important for the equipment as well as for its operation; therefore, getting the equipment tuned up from the start can greatly help it to function properly.