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Valve positioner

Valve positioner, which is divided into pneumatic valve positioner, electric-pneumatic valve positioner and intelligent valve positioner according to its structure, is the main accessories of regulating valve. It is usually used with pneumatic regulating valve. It receives the output signal of the regulator, and then controls the pneumatic regulating valve with its output signal. When the regulating valve moves, the position of the valve stem is controlled. The displacement is fed back to the valve positioner by mechanical device, and the valve position status is transmitted to the upper system by electric signal.