Model Code Explanation (D661-4385C)

• D661: Series (ISO 4401‑05, 24 VDC integrated electronics, bushing‑type spool)

• 4: High‑flow platform

• 38: 380 L/min nominal flow (Δp=35 bar)

• 5: Ultra‑high dynamic response (5–6 ms step response)

• C: High‑stability electronics, enhanced null performance

• (Implied G): Standard spool (zero‑lap, linear), ServoJet® pilot

Technical Specifications

Hydraulic

• Nominal Flow (Δp=35 bar): 380 L/min (±8%)

• Max Operating Pressure (P/A/B): 350 bar (5,000 psi)

• Pilot Pressure (X): 21–280 bar (internal P or external X)

• T Port Pressure (Y internal): 210 bar; (Y external): 350 bar

• Fluid: Mineral oil (DIN 51524), NBR seals (−20°C to +80°C)

• Temperature: Ambient −20°C to +60°C; Fluid −20°C to +80°C

• Weight: Approx. 5.7 kg

Electrical

• Supply: 24 VDC (18–32 VDC), quiescent 230 mA, dynamic ~500 mA

• Command Signal: ±10 V differential (10 kΩ impedance)

• Feedback Signal: Optional 4–20 mA (single LVDT, ±0.02% FS accuracy)

• Connector: 6+PE (EN 175201‑804), IP65 (connected)

• Step Response (0→100%): ≤5–6 ms @ 210 bar

• Hysteresis: <0.20% (closed‑loop)

• Linearity: <±0.25%

• Resolution: <0.08%

Interface & Communication

• Electrical: 6+PE connector; ±10 V command, 24 VDC power, optional 4–20 mA LVDT feedback

• Feedback: Single integrated LVDT (full‑stroke closed‑loop, optional)

• Ports: P, A, B, T; optional external X (pilot) and Y (return)

Key Features

• 380 L/min High Flow: Matches ultra‑high‑flow system demands

• 5–6 ms Ultra‑High Response: Fastest dynamics in D661‑4xxx series

• High‑Stability Electronics: Premium null stability for long‑term precision

• ServoJet® Pilot: Reduced hysteresis, improved pressure gain

• ±10 V Analog Interface: Wide compatibility with industrial controllers

Applications

• High‑speed & precision industrial test benches

• Ultra‑precision forging presses and steel rolling mills

• Large high‑speed injection molding and die‑casting machines

• High‑tonnage hydraulic machinery requiring ultra‑fast response

• Closed‑loop systems prioritizing maximum speed and precision

Compatibility

• Interchangeable with D661‑4384C/4380E/4375B (ISO 4401‑05)

• Drop‑in upgrade for lower‑flow D661‑4209/4196

• Requires 24 VDC supply, ±10 V controller, ISO 4401‑05 manifold