Model Code Explanation (D661-4536C)

• D661: Series (ISO 4401‑05 mounting, integrated 24 VDC electronics)

• 4: 4‑way, zero‑lap, linear flow characteristic

• 53: Rated flow ≈ 150 L/min (Δp = 35 bar per land)

• 6: Standard‑dynamic response, single LVDT feedback, basic null stability

• C: Standard performance, non‑explosion‑proof

Technical Specifications

Part Number: D661-4536C

Mounting

Control Function

Hydraulic Parameters

• Rated Flow (Δp = 35 bar): 150 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), viscosity 15–45 mm²/s

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

• Weight: Approx. 5.9–6.1 kg

Electrical Parameters

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

• Command Signal: ±10 VDC (differential, 10 kΩ impedance) or 4–20 mA

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

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

• Step Response (0→100%): 12–16 ms @ 210 bar (standard dynamics for 150 L/min)

• Hysteresis: <0.25% (closed‑loop)

• Linearity: <±0.30%

• Resolution: <0.10%

Interface & Communication Configuration

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

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

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

• Seal Material: NBR (standard) or FKM (optional, high‑temperature)

Core Functions

1. 150 L/min High Flow: Mid‑high flow in D661‑4xxx series, balancing capacity and dynamics

2. Standard‑Dynamic Response: 12–16 ms step response for stable, high‑flow operation

3. Closed‑Loop Spool Control: Integrated LVDT ensures real‑time position feedback and consistent precision

4. ServoJet® Pilot: Jet‑pipe design reduces energy use, improves contamination resistance, and lowers hysteresis

5. Integrated Digital Amplifier: On‑board PID, ramp generator, fault diagnostics, and EMC protection

Applicable Scenarios

• Metal Forming: Large injection molding, die‑casting, heavy stamping presses (high flow, high force)

• Heavy Machinery: Steel mill roll gap control, large hydraulic presses, material handling

• Test Systems: Aerospace component testing, high‑flow vibration simulation tables

• Industrial Automation: High‑speed positioning, force control, and closed‑loop hydraulic systems

Compatibility & Installation Notes

• Mechanical: Interchangeable with D661 (G/C/A), D662/D663 (ISO 4401‑05)

• Upgrade: Drop‑in replacement for lower‑flow D661‑4xxx models (e.g., 4496E/4479C)

• System Requirements: 24 VDC supply, analog controller (±10 V in / 4–20 mA out), ISO 4401‑05 manifold

Usage & Maintenance Instructions

1. Installation: Mount on flat surface (flatness ≤0.02 mm/100 mm; Ra <1 μm) with M6×55/60 bolts (13 Nm, diagonal)

2. Fluid: ISO VG 32–46, NAS 1638 cleanliness class ≤8

3. Maintenance: Replace internal filter every 5,000 hours; inspect leaks/connectors periodically

4. Precautions: Avoid voltage spikes/reverse polarity; do not open standard (C) models in field