Model Definition

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

6397C = Spool/sleeve assembly; rated flow 90 L/min @ ΔP=35 bar (high‑response linear trim, no LVDT, standard null, C‑code configuration)

Typical full config example: G90JOAA6VSM2HA

G90 = 90 L/min rated flow & high frequency response

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

6 = 6+PE connector, IP65

VSM2 = NBR seals, wide temperature range, standard pilot

HA = Fail‑safe centering, no LVDT

Technical Specifications

Hydraulic Parameters

Rated flow: 90 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: 10–16 ms (0→100%, 210 bar)Moog Inc.

Hysteresis: <0.12%

Resolution: <0.05%

Null drift: <1.5% (ΔT=55 K)

Null leakage: <18 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: None (open‑loop)

Connector: 6+PE, IP65Moog Inc.

Current draw: ≤800 mA

Physical & Environmental

Operating temperature: −40 ℃ to +85 ℃

Weight: approx. 5.7 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 mA

Status: Fault alarm output

Core Functions

High‑Response ServoJet® Pilot: Optimized for 90 L/min, fast dynamic response, excellent dirt tolerance

Integrated PID Amplifier: Onboard dead‑zone compensation, thermal/overload protection, stable null

Open‑Loop Precision Control: High linearity and repeatability for cost‑effective motion control

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

90 L/min High‑Flow Dynamics: Tuned for medium‑to‑large systems requiring speed and accuracy

Application Scenarios

Industrial automation: Heavy‑duty CNC machines, large hydraulic presses, high‑force injection molding equipment

Test equipment: Structural fatigue testers, high‑load vibration tables, actuator test benches

Metallurgy: High‑precision tension control, heavy‑duty AGC roll gap control

Energy: Wind turbine pitch control, marine heavy‑duty auxiliary hydraulics

Usage & Maintenance

Installation: Horizontal/vertical mounting; minimize vibration

Fluid: ISO VG46 mineral oil; maintain NAS 1638 Class 6 cleanlinessMoog Inc.

Commissioning: Apply 24 VDC; connect ±10 V/±10 mA command; calibrate zero/gain

Maintenance: Check contamination every 3 months; calibrate every 6 months; avoid long idle periods at high pressure