Model Definition

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

5003 = Spool/sleeve assembly; rated flow 250 L/min @ ΔP=35 bar (max‑flow, ultra‑low hysteresis trim)

Typical full config example: P250HAAM7NSX2‑H

P250 = 250 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

H = Ultra‑low hysteresis ServoJet® pilot stage

Technical Specifications

Hydraulic Parameters

Rated flow: 250 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: 17–20 ms (0→100%, 210 bar)Moog Inc.

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)

Connector: 7+PE, IP65

Current draw: ≤1000 mA

Physical & Environmental

Operating temperature: −40 ℃ to +85 ℃

Weight: approx. 11.7 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)

Status: Fault alarm output

Core Functions

Ultra‑Low Hysteresis Max‑Flow ServoJet® Pilot: Optimized for 250 L/min, minimal hysteresis, excellent repeatability

Integrated High‑Precision PID Amplifier: Onboard dead‑zone compensation, thermal/overload protection, enhanced null stability

LVDT Closed‑Loop Feedback: Superior linearity and resolution for critical motion control

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

250 L/min High‑Flow Precision: Tuned for large‑scale hydraulic systems demanding both high flow and tight control

Application Scenarios

Metallurgy: Ultra‑precision AGC roll gap control for heavy plate mills, high‑accuracy tension control

Test equipment: High‑precision structural fatigue testers, multi‑axis vibration simulation tables, high‑load actuator test benches

Industrial automation: Large ultra‑precision CNC machine tools, 1000‑ton+ hydraulic presses with tight tolerance, large injection molding machines

Energy & heavy industry: High‑power wind turbine pitch control (precision critical), marine main hydraulic systems, steel mill main drive control

Usage & Maintenance

Installation: Horizontal/vertical mounting; avoid severe vibration/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/gain via 4–20 mA feedback

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