Model Definition

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

4826 = Spool/sleeve assembly; rated flow 60 L/min @ ΔP=35 barMoog Inc.

Typical full config example: P60HXAM6NSM2‑A

P60 = Medium‑low flow & high frequency response versionMoog Inc.

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

6 = 6+PE connector, IP65Moog Inc.

NSM2 = NBR seals, wide temperature range, LVDT feedback 4–20 mAMoog Inc.

A = Standard ServoJet® pilot stageMoog Inc.

Technical Specifications

Hydraulic Parameters

Rated flow: 60 L/min (ΔP=35 bar)Moog Inc.

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

Step response: 5–8 ms (0→100%, 210 bar)

Hysteresis: <0.2%Moog Inc.

Resolution: <0.1%

Null drift: <1.0% (ΔT=55 K)

Null leakage: <12 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: 6+PE, IP65Moog Inc.

Current draw: ≤650 mA

Physical & Environmental

Operating temperature: −40 ℃ to +85 ℃

Weight: approx. 8.5 kg

Interface & Communication Configuration

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

Electrical interface:

Power: 24 VDC, GND, PEMoog Inc.

Command: ±10 V / ±10 mAMoog Inc.

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

Status: Fault alarm output

Core Functions

ServoJet® pilot stage: Superior contamination resistance, low null drift, extended service lifeMoog Inc.

Integrated high‑response amplifier: Built‑in PID, dead‑zone compensation, overload protectionMoog Inc.

LVDT closed‑loop feedback: High linearity and precision across full strokeMoog Inc.

Fail‑Safe centering: Spool returns to neutral on power lossMoog Inc.

Medium‑low flow dynamics: Optimized for 60 L/min with ultra‑fast response for precision applications

Application Scenarios

Metallurgy: Precision gap control for small rolling mills, tension control for thin strips

Test equipment: High‑precision dynamic material testers, small‑scale high‑frequency vibration tables

Industrial automation: Small CNC machine tools, precision hydraulic presses, standard injection molding machines

Energy & heavy industry: Wind turbine pitch control, marine auxiliary hydraulic systems, industrial robot hydraulic drives

Usage & Maintenance

Installation: Horizontal/vertical mounting; avoid severe vibration

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 feedback

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