Siemens 771-3STF2 I/P Transducer

Technical SpecificationsModel:771-3STF2 Brand:Siemens Product Type:I/P Current to Pneumatic Transducer Input Signal:4-20mA DC Output Signal:3-15 psi pneumatic Supply Air:20-100 psi clean dry instrument air Mounting:Field direct mount on valve yoke or panel mount Operating temperature:-20℃ ~ +70℃ Storage temperature:-40℃ ~ +85℃ Relative humidity:5%~95%, non-condensing Weight:1.1kg Dimension:85mm120mm145mm

System compatibility771-3STF2 belongs to Siemens Moore Series 77 I/P transducer family. It receives analog control signal from DCS, single-loop controller or PLC, outputs pneumatic pressure signal to drive spring-diaphragm control valve actuators. Compatible with APACS+ and QUADLOG control systems.

FunctionThis I/P transducer converts 4-20mA electrical control signal into proportional 3-15psi pneumatic pressure. It receives command signal from process controller and supplies pneumatic power to valve actuator to adjust valve opening. It realizes electric-pneumatic signal conversion for closed-loop regulation of temperature, pressure, flow and liquid level. Built-in feedback mechanism stabilizes output pressure and improves valve positioning precision.

InstallationCut off instrument air supply and electric signal before installation. Mount transducer on valve yoke or panel bracket. Wire 4-20mA control signal to electrical terminals. Connect instrument air supply and pneumatic output port to valve actuator. Perform zero and span calibration after air supply is stabilized.

InterfaceElectrical signal terminal block, pneumatic air inlet, pneumatic output port, adjustment screws for zero and span.

FeatureMoore 77 series I/P converter, 4-20mA input / 3-15psi output, compact field mount design, stable pneumatic output, built-in mechanical feedback, explosion-proof optional version. Obsolete legacy spare part, used for pneumatic control valve system maintenance and replacement.

DiagnosticNo pneumatic output: check instrument air supply, filter blockage and 4-20mA input signal. Output pressure drift: re-calibrate zero and span, inspect diaphragm for leakage. Slow response: check air pipeline restriction and signal wiring loose contact.

Product BriefSiemens 771-3STF2 is Moore Series 77 I/P current to pneumatic transducer, widely used in petrochemical, power and pulp & paper industries for electric signal conversion to operate pneumatic control valves.

DisclaimerAll parameters are for reference only and shall not be used as the basis for quotation. Goods are scarce, overseas delivery lead time is 3-7 working days. It is only used for equipment maintenance and renovation.