Description
Masoneilan SVI2-21123121
Technical Specifications 4-20mA analog control signal input; HART digital communication protocol; Pneumatic supply air 20-150 psi; Valve stem position feedback sensor; Operating temperature range -40°C to +85°C; Two-wire loop powered design; Local LCD display; Push button configuration keys.
Functional Features Closed-loop valve stem position regulation; HART communication for remote configuration and diagnosis; Automatic valve stroke calibration; Built-in valve health diagnostic; Local LCD display for position and fault information; Push button on-site parameter setting; Anti-jamming design for industrial field environment.
Application Scenarios Petrochemical process control valve; Refinery flow regulation valve; Natural gas pipeline control valve; Chemical plant reactor control valve; Power plant steam regulating valve; Water treatment flow control valve.
Performance Parameters Position control accuracy maintains high level; Response speed of valve adjustment stable; HART communication data transmission reliable; Position feedback repeatability consistent; Long-term operation drift stays within specified range.
Material Composition Die cast aluminum housing; Stainless steel position feedback linkage; Piezoelectric pneumatic pilot valve; Magnetic position sensor; LCD display module; Multi-layer PCB control circuit; Protective coating on metal housing.
Structural Features Compact rectangular die-cast enclosure; Side pneumatic supply and output ports; Bottom mechanical linkage connects valve stem; Front panel LCD screen and operation push buttons; Electrical cable entry gland; Internal isolated pneumatic and electronic chambers.
Working Principle 4-20mA setpoint signal comes from process controller. Positioner compares setpoint value with actual valve stem position measured by feedback sensor. Control circuit drives piezoelectric pilot valve to adjust output air pressure to valve actuator. Actuator moves valve stem until actual position matches setpoint. HART protocol superimposes digital data on 4-20mA loop for remote configuration, parameter reading and valve diagnostic data upload.
Installation Requirements Mount positioner firmly on valve actuator bracket; Align feedback linkage with valve stem stroke; Connect dry and filtered instrument air supply; Use shielded twisted pair cable for 4-20mA signal wiring; Fix cable gland to prevent moisture ingress.
Precautions for Use Supply instrument air must be dry and free of oil and particulate contaminant; Perform auto calibration after installation; Do not exceed rated supply air pressure; Protect housing from corrosive gas and rain exposure; Verify HART communication loop resistance before remote operation.
