Product Overview
The DG4V-3-2C-M-KU4-H-7-50-JA81 and DG4V-3-2C-M-P7-H-7-56 are direct-operated solenoid directional control valves from Eaton Vickers’ (now Danfoss Power Solutions) DG4V-3 series. This series represents one of the most widely used NG6 (CETOP D03 / ISO 4401-03) directional valve product lines in industrial hydraulics, featuring subplate mounting.
DG4V-type directional valves are solenoid-actuated directional spool valves that control the start, stop, and direction of fluid flow. The valve consists of the housing, wet armature solenoids, control spool, and return springs. In the de-energized condition, the control spool is held in the central position by the return springs. When energized, the wet armature solenoid acts via the plunger on the control spool, pushing it to the required end position.
Both models feature 2C-type spool—closed center with all ports blocked—making them ideal for double-acting cylinder control with load-holding capability. The DG4V-3-2C-M-KU4-H-7-50-JA81 is equipped with KU4-type electrical connection (top-exit flying leads, mobile equipment configuration), while the DG4V-3-2C-M-P7-H-7-56 features P7-type connection. Both include M-type manual override (push-pin type) for commissioning and emergency operation.
The DG4V-3 series features an optimized damping orifice design that delivers a soft shift function, providing smoother actuator acceleration and deceleration control than conventional solenoid valves, minimizing hydraulic shock while improving system reliability and extending component life. The valve is tested for fatigue life and endurance exceeding 20 million cycles.
As a direct OEM-replacement solution, this valve maintains 100% mechanical and functional interchangeability with the original Eaton Vickers unit. Every valve undergoes rigorous simulation testing—including pressure cycling, thermal variation, and full-stroke endurance validation—to guarantee factory-grade performance.
Technical Specifications
DG4V-3 Series General Specifications (NG6 / CETOP D03):
Brand: Eaton Vickers (Danfoss Power Solutions)
Valve Type: Direct operated solenoid directional spool valve
Nominal Size: NG6 (CETOP D03 / NFPA D03)
Mounting Interface: ISO 4401-03 / CETOP 3
Mounting Type: Subplate mounting
Spool Type: 2C (closed center, all ports blocked)
Spool/Spring Arrangement: C – Spring centered (double solenoid)
Max. Operating Pressure: 350 bar (5075 psi) on ports P, A & B
Max. Tank Port Pressure: 210 bar (3045 psi)
Max. Flow: 80 L/min (21 USgpm) – high performance specification
Design Series: 50 / 56 Design
Control Type: Wet armature solenoid direct actuation
Coil Voltage: 24V DC (H code)
Electrical Connection: KU4 – Top-exit flying leads (mobile configuration); P7 – Specific connector configuration
Manual Override: M – Push-pin type manual override
Seal Material: Standard NBR, optional Viton available
Body Material: Cast iron
Response Time – On: 25–40 ms
Response Time – Off: 20–30 ms
Protection Class: IP65
Weight: Approx. 2.3 kg
Duty Cycle: 100% ED
Key Technical Advantages
1. 2C Closed Center Spool – Superior Load-Holding Capability
Both models feature 2C-type spool with all ports (P, A, B, T) blocked in the center position. This center condition ensures reliable actuator locking when solenoids are de-energized, making these valves particularly suitable for load-holding applications with double-acting cylinders.
2. Wet Armature Solenoid Design – Long Service Life and High Reliability
DG4V-3 series valves feature wet armature solenoids, with the armature fully immersed in pressure oil. This design effectively lubricates moving parts, reduces friction and wear, and significantly improves solenoid heat dissipation, extending solenoid service life. Solenoid coils can be changed quickly and easily without leakage from the hydraulic system.
3. Optimized Soft Shift Function – Reduced Hydraulic Shock
DG4V-3 series valves feature an optimized damping orifice design, with milled metering notches on the spool enabling precise control of flow rate change during shifting. This provides smoother actuator acceleration and deceleration control than conventional solenoid valves, resulting in minimum hydraulic shock, more reliable systems with longer component life, and less downtime.
4. Proven Fatigue Life – Over 20 Million Cycles Tested
DG4V-3 series valves are tested for fatigue life and endurance exceeding 20 million cycles. NFPA fatigue rating of 350 bar (5075 psi) ensures sustained machine productivity and high uptime.
5. Drop-In Interchangeability – Minimized Downtime and Retrofit Costs
The valve strictly adheres to Eaton Vickers’ original mounting dimensions and functional specifications, with ISO 4401-03 / CETOP 3 interface compliance. The DG4V-3 series is a direct equivalent replacement for Rexroth 4WE6 and Yuken DSG-01 series. Whether for new system design or legacy system upgrades, this valve offers 100% mechanical and electrical interchangeability with the original Eaton Vickers unit—eliminating the need for manifold modifications or piping changes, significantly reducing downtime and retrofit expenses.
Application Areas
Mobile and Construction Equipment – The KU4 flying lead configuration of DG4V-3-2C-M-KU4-H-7-50-JA81 is specifically designed for mobile applications, including excavators, drilling rigs, and concrete pump trucks
Injection Molding Machinery – Directional switching and sequence control for hydraulic actuators
Hydraulic Presses – Directional switching for slide lifting and pressing operations
Machine Tool Hydraulic Systems – Directional control for table reciprocation and tool feed/retract
Material Handling Equipment – Directional control for forklifts and lifting platforms
Industrial Automation Lines – Directional switching and logic control for hydraulic actuators
Expert Maintenance Tips
1. Ensure Solenoid Pressure Chamber is Oil-Filled
Proper operation of wet armature solenoids requires the pressure chamber to be completely filled with oil. During initial installation or after extended shutdown, ensure no air remains trapped in the solenoid chamber—air entrapment will affect solenoid thrust characteristics and response speed.
2. Fluid Cleanliness Management
DG4V-3 series valves have specific fluid cleanliness requirements. The clearance between spool and bore is extremely tight—contaminants can cause spool sticking or abnormal wear. Install filters with a minimum rating of 10μm upstream of the valve and regularly monitor fluid contamination levels.
3. Electrical Connections and Voltage Matching
DG4V-3-2C-M-KU4-H-7-50-JA81 features KU4-type top-exit flying leads (mobile equipment configuration); DG4V-3-2C-M-P7-H-7-56 features P7-type connector configuration. Both operate on 24V DC coil voltage. Verify that the supply voltage matches the valve’s electrical specifications prior to installation—DC solenoids must never be connected to AC power.
4. Seal Material Compatibility Confirmation
DG4V-3 series valves feature standard NBR seals. Confirm that the seal material is compatible with the hydraulic fluid used in the system. For high-temperature or special media applications, Viton (Fluorocarbon) seals are available as an option.
5. Installation and Sealing
Carefully review the Eaton Vickers product documentation prior to installation. Ensure the mounting surface is flat and smooth, with ISO 4401-03 interface compliance. DG4V-3 series uses M5 mounting bolts—tighten evenly to specified torque. Take care not to damage or omit seals during assembly.
6. Periodic Inspection and Maintenance
Regularly verify the valve’s shifting response time. If sluggish response or abnormal heating is detected, inspect the solenoid condition and check for spool sticking. For systems that have been idle for extended periods, perform thorough system circulation filtration before restart.
