Description

MOOG G771K203A-H04FOFA4VJ4 Two-Stage Electro-Hydraulic Servo Valve

Basic Parameter Overview

• Full Model: G771K203A-H04FOFA4VJ4
• Brand: MOOG (USA, top-tier aerospace-grade servo valve manufacturer)
• Series: G771 compact two-stage dry torque motor servo valve family
• Structure: 2-stage double nozzle-flapper pilot control + sliding spool power stage, dry torque motor design
• Warranty: One Year

Core Hydraulic Specifications

1. Rated Supply Pressure: 210 bar (3000 PSI) maximum working hydraulic pressure
2. Flow Rate: Standard calibrated flow for G771K203 base model ≈17 L/min (4.4 GPM) at rated pressure drop
3. Control Signal: Standard ±15mA analog differential current input (the suffix code H04FOFA4VJ4 defines coil impedance, feedback type, port configuration, explosion-proof certification, electrical connector pinout and null adjustment mode)
4. Mounting Standard: ISO 10372-02-02-0-92 standard 4-hole flange installation base
5. Fluid Compatibility: Suitable for mineral hydraulic oil, phosphate ester fire-resistant fluid, synthetic aviation hydraulic fluid

Electrical & Performance Index

• Hysteresis: ≤0.5% ultra-low hysteresis for closed-loop high-precision regulation
• Resolution: Infinite proportional micro-resolution, no step dead zone
• Frequency Response: High dynamic response bandwidth, stable under high-frequency load fluctuation
• Fail-Safe Logic: Automatically returns to neutral zero position when electrical control signal is lost, avoiding runaway actuator stroke
• Protection Grade: IP65 valve body housing; suffix code contains explosion-proof certification for Zone 1/2 hazardous gas environments
• 

Environmental & Mechanical Data

• Operating Temperature: -20°C ~ +85°C
• Storage Temperature: -40°C ~ +120°C
• Vibration Resistance: Aerospace-grade anti-vibration and shock resistance, withstands long-term mechanical oscillation of turbines and reciprocating compressors
• Weight: Approximately 3.0 kg
• Cooling: Self-convection passive cooling, no fan required

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Product Overview

The MOOG G771K203A-H04FOFA4VJ4 is a high-reliability closed-loop electro-hydraulic servo valve, widely matched with GE Mark VI / Mark VIe, Woodward 505/5000 turbine governor control systems as the core actuator for steam/gas turbine fuel valve, compressor anti-surge control, inlet guide vane (IGV) and throttle position closed-loop regulation.