1. General Description

2. Model Definition (D634-341C)

• D634: Series = Direct drive servo valve, ISO 4401 Size 05 (NG10)Moog Inc.

• 341: Configuration code (150 L/min high-flow spool, 24 VDC industrial electronics)

• C: Revision C (latest baseline)

3. Hydraulic Specifications

• Mounting: ISO 4401 Size 05 (NG10)Moog Inc.

• Max Working Pressure (P/A/B): 350 bar (5,000 psi)Moog Inc.

• T Port Pressure (no Y port): 50 bar (725 psi)Moog Inc.

• T Port Pressure (with Y port): 350 bar (5,000 psi)Moog Inc.

• Rated Flow (Δp=35 bar/orifice): 150 L/min (39.6 gpm)

• Maximum Flow: ≈220 L/min

• Internal Leakage: ≤3.0 L/min

• Fluid: Mineral oil (ISO 11158 / DIN 51524)Moog Inc.

• Fluid Temp: -20 °C to +80 °C

• Fluid Cleanliness: ISO 4406 17/14/11

• Weight: ≈6.8 kg

4. Dynamic Performance

• Full-Stroke Step Response: ≤25 msMoog Inc.

• -3 dB Bandwidth: 45–55 Hz

• Hysteresis: <0.2% full scale

• Resolution: <0.1% full scale

• Null Drift (ΔT=55 K): <1.5% full scale

5. Electrical Specifications

• Supply Voltage: 24 VDC (18–32 VDC)Moog Inc.

• Max Operating Current: 2.5 A

• Standard Command Signal: ±10 VMoog Inc.

• Optional Signals: ±10 mA, 4–20 mAMoog Inc.

• Spool Position Feedback: 0–10 VDC

• Connector: M18, 6 pins + PE, IP65Moog Inc.

• Ambient Temp: -20 °C to +60 °C

• EMC: CE compliant

6. Key Features

• Pilotless design: Easy installation, no external pilot supplyMoog Inc.

• Ultra-high flow: 150 L/min for high-demand hydraulic systems

• Pressure-independent dynamics: Stable response under varying loadsMoog Inc.

• Fail-safe: Spring-centered, returns to neutral on power lossMoog Inc.

• Integrated electronics: Compact, protected, ready for useMoog Inc.

7. Applications

• High-flow hydraulic presses

• Large-scale structural fatigue test rigs

• Heavy-duty industrial automation

• Closed-loop position/velocity/pressure control for large machinery