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In the power supply units commonly found in the hardware structure of Fisher positioners, only a few intelligent valve positioners are designed with a four-wire or three-wire system, requiring a dedicated external power supply; such units are equipped to accept an external voltage source. Most intelligent valve positioners are two-wire instruments; they obtain their operating power from the analog control signals of the control system and the instrument. In such cases, a power conversion unit is connected in parallel to the input. The conventional approach involves using a voltage regulator to generate the required voltage, which is then used by integrated components to convert it into the operating voltage for the interface as well as the drive voltage needed by the output subsystem. Fieldbus types are connected via communication interfaces to obtain power from the bus network and simultaneously receive digital control signals. When input components are used, they serve to connect the current control signal (the set value) with the feedback signal from the valve position sensor, which detects the stroke of the control valve; this facilitates the primary function of position control. The valve position feedback signal of the Fisher locator is transmitted to the valve position sensor by means of mechanical connections such as a feedback rod, via the valve stem (axis) of the control valve; for measurement, contact-type potentiometers and sliding resistors are commonly used, or non-contact Hall elements and magnetoresistive displacement (angle) sensors are employed. Auxiliary input components are used to separate the signal inputs for the primary positioning control functions, allowing other auxiliary signal inputs to be analyzed as a separate module. It supports the expansion of functions and the implementation of predictive maintenance, such as monitoring gas supply pressure, output drive pressure, and the internal temperature of the actuator; it can also receive signals from external sensors (filling leakage sensors, noise sensors, pressure switches, etc.), as well as digital input signals. The auxiliary input components are integrated with the main input components to form the input interface of the data processing unit. Things to keep in mind when installing the dvc6200: 1. When adjusting the dvc6200, use the pressure gauge to turn the adjustment nut until the desired pressure value is reached. 2. The inlet and outlet of the dvc6200 should have a certain length of straight pipe (generally 10 times the diameter of the inlet valve and 5 times the diameter of the outlet valve), and pressure gauges, stop valves, and bypass systems should be installed for adjustment and maintenance. 3. If the diameter of dvc6200 is reduced, the degree of reduction should not be excessive; it generally should not exceed 2-3, as the diameter reduction required by the manufacturing process means that the straight pipe section should be as long as possible. 4. The main application of dvc6200 is to adjust controlled parameters without changing those parameters themselves. 5. The controlled pressure parameter of dvc6200 should not approach or reach the upper limit of the selected pressure adjustment range. A certain balance should be maintained according to the I-art conditions. 6. The medium should flow in the direction indicated by the arrows in dvc6200. During the I process, reverse flow of the medium is not allowed. 7. When installing flammable and explosive gases such as natural gas indoors, if the area has poor ventilation or no gas leakage alarm system, an outdoor oil pressure pump should be connected to the actuator to ensure safety. (Pressure adjustment after dvc6200 is connected to the upper film cover connector, pressure adjustment before dvc6200 is connected to the lower film cover connector). 8. The filter should be installed in front of the DVC6200; if installation is not possible, the pipeline should be cleaned to prevent welding slag or other pipeline deposits from blocking the DVC6200 and causing damage. 9. When the medium temperature is below 80°C, the dvc6200 can be installed either upright or inverted. When the medium temperature is above 80°C, the dvc6200 must be installed in inverted position, with the valve body open and the actuator in that position.