Positioners are devices used in conjunction with pneumatic drives to precisely control the regulating valve and achieve a predetermined valve opening value
When there is no positioner, the incoming signal is directly transmitted to the pneumatic drive. If a positioner is installed, it responds to the incoming signal and, if necessary, provides a modified signal to the drive, ensuring that the valve is always in the desired position

Positioners enable more precise control over the process by increasing the speed and accuracy of the response to changes in the process itself and changes in the valve, such as friction, increased resistance due to the presence of fluid in the valve, etc