Model Definition

• D661 = Series (integrated electronics, 24 VDC, NG10)

• 4923 = Spool/sleeve assembly; rated flow 200 L/min @ ΔP=35 bar (high‑response, low‑hysteresis trim)

• Typical full config example: P200HAAM7NSX2‑C

  • P200 = 200 L/min rated flow & high frequency response

  • HAAM = Standard hydraulic layout, 24 VDC, ±10 V/±10 mA command, centered null

  • 7 = 7+PE connector, IP65

  • NSX2 = NBR seals, wide temp range, LVDT 4–20 mA feedback

  • C = High‑response ServoJet® pilot stage

Technical Specifications

Hydraulic Parameters

• Rated flow: 200 L/min (ΔP=35 bar)

• Max working pressure: 350 bar (P/A/B); 210 bar (internal drain T) / 350 bar (external drain T)Moog Inc.

• Step response: 14–17 ms (0→100%, 210 bar)

• Hysteresis: <0.15%

• Resolution: <0.08%

• Null drift: <1.8% (ΔT=55 K)

• Null leakage: <28 mL/min

• Fluid cleanliness: NAS 1638 Class 6 / ISO 4406 18/15Moog Inc.

Electrical Parameters

• Power supply: 24 VDC (18–32 VDC)Moog Inc.

• Control signal: ±10 V (differential) or ±10 mAMoog Inc.

• Feedback signal: 4–20 mA (LVDT spool position)Moog Inc.

• Connector: 7+PE, IP65

• Current draw: ≤900 mA

Physical & Environmental

• Operating temperature: −40 ℃ to +85 ℃

• Weight: approx. 10.8 kg

Interface & Communication Configuration

• Hydraulic interface: P/A/B/T, ISO 4401‑05 (NG10)

• Electrical interface:

  • Power: 24 VDC, GND, PE

  • Command: ±10 V / ±10 mAMoog Inc.

  • Feedback: 4–20 mA (spool position)Moog Inc.

  • Status: Fault alarm output

Core Functions

• High‑Response ServoJet® Pilot: Fast dynamic response, minimal null shift, robust contamination tolerance

• Integrated Digital Amplifier: Onboard PID, dead‑zone compensation, thermal & overload protection

• LVDT Closed‑Loop Feedback: Excellent linearity and repeatability across full stroke

• Fail‑Safe Centering: Spool returns to neutral on power loss

• 200 L/min Flow Optimization: Balanced flow and response for medium‑to‑large hydraulic systems

Application Scenarios

• Metallurgy: High‑speed AGC roll gap control for medium plate mills, precise tension control

• Test equipment: Dynamic material fatigue testers, medium‑force vibration tables, actuator performance benches

• Industrial automation: Large CNC machine tools, medium‑tonnage hydraulic presses, plastic injection molding machines

• Energy & heavy industry: Wind turbine pitch control (medium power), marine auxiliary hydraulic systems, steel mill auxiliary drives

Usage & Maintenance

• Installation: Horizontal/vertical mounting; avoid severe vibration and shock

• Fluid: ISO VG46 mineral oil; maintain cleanliness per NAS 1638 Class 6Moog Inc.

• Commissioning: Apply 24 VDC power; connect ±10 V/±10 mA command; calibrate zero and gain via 4–20 mA feedbackMoog Inc.

• Maintenance: Inspect fluid contamination every 3 months; calibrate zero/gain every 6 months; avoid long idle periods at high pressure