The Samson 3730-3 is a self-calibrating electropneumatic positioner designed for attachment to pneumatic control valves. It automatically adapts to valve and actuator characteristics, ensuring precise position control from 3.6 to 300 mm travel or 24 to 100° opening angle.

• Self-calibrating operation with automatic valve adaptation
• HART® communication protocol for advanced control
• Four different initialization modes for flexible setup
• Calibrated travel sensor without wear-prone gears
• IP67 rated for superior dust and water protection
• Two-wire system with low electrical load of 410 Ω
• Integrated EXPERTplus diagnostics for control valves
• Adjustable output pressure limitation and tight-closing function
• Continuous zero point monitoring and temperature sensing
• Operating hours counter for maintenance planning
• Programmable position alarms and self-diagnostics

The positioner mounts directly on pneumatic control valves and maintains precise correspondence between the valve position (controlled variable) and the control signal (set point). It continuously compares the electrical control signal from the control system to the actual travel or rotational angle of the control valve, then issues the appropriate signal pressure to the pneumatic actuator for accurate positioning.