Model Definition

D661: Product series with integrated electronics, 24 VDC power supply and NG10 installation dimension

4651: Spool and sleeve assembly, rated flow 30 L/min at 35 bar pressure drop

G35JOAA6VSX2HA: Complete configuration code

G: Standard spool with ServoJet® pilot stage

35: High frequency response class, bandwidth up to 120 Hz

J: 24 VDC power supply, supports ±10 V or ±10 mA analog control signal

O: Centered null position with fail-safe function

AA: Standard hydraulic and electrical base configuration

6: 6+PE electrical connector with IP65 protection rating

VS: Special sealing material for wide temperature range

X2HA: LVDT spool position feedback with 4-20 mA signal output and standard performance parameters

Technical Specifications

Hydraulic Parameters

Rated flow: 30 L/min (ΔP=35 bar)

Maximum operating pressure: 350 bar for port P, A and B; 210 bar for internal drain port T, 350 bar for external drain port T

Step response: 6.5-14 ms (0 to 100% stroke under 210 bar)

Hysteresis: Less than 0.2%

Resolution: Less than 0.1%

Temperature drift: Less than 1.5% (ΔT=55 K)

Null leakage: Less than 8 mL/min

Recommended fluid cleanliness: NAS 1638 Class 6 or ISO 4406 18/15

Electrical Parameters

Power supply: 24 VDC (18-32 VDC)

Control signal: ±10 V or ±10 mA

Feedback signal: 4-20 mA from LVDT spool position sensor

Electrical connector: 6+PE, IP65

Working current: Maximum 300 mA

Physical & Environmental Parameters

Operating temperature: -40 ℃ to +85 ℃

Weight: Approximately 5.1 kg

Interface & Communication Configuration

Hydraulic interface: P, A, B, T four ports complying with ISO 4401-05 standard

Electrical interface: Terminals for 24 VDC power, GND and PE; terminals for ±10 V/±10 mA command signal; 4-20 mA position feedback terminals and fault status output terminals

Core Functions

ServoJet® pilot stage features strong anti-pollution capability, low null drift and long service life

Integrated closed-loop amplifier is equipped with PID regulation, dead zone compensation and overload protection

LVDT position feedback ensures excellent linearity and positioning accuracy throughout the full stroke

Fail-safe design enables the spool to return to neutral position automatically once power is cut off

High bandwidth design meets the requirements of fast dynamic control

Application Scenarios

Metallurgical industry: Medium-flow AGC roll gap control and tension control systems

Testing equipment: Material testing machines, fatigue test benches and small vibration tables

Industrial automation: Precision machine tools, injection molding machines and hydraulic forming equipment

Energy and heavy industry: Wind turbine pitch control, auxiliary control of shield machines and marine steering systems

Usage & Maintenance

Install the valve horizontally or vertically and keep away from intense vibration

Use qualified hydraulic oil and maintain fluid cleanliness above NAS 1638 Class 6

Connect 24 VDC power and input ±10 V or ±10 mA command signal during commissioning, then complete zero adjustment and gain calibration according to 4-20 mA feedback signal

Check hydraulic fluid contamination regularly. Calibrate null position and gain every six months. Avoid long-term standby under high pressure without control command.