Product Overview
The KSO-G02-2BB-30, KSO-G02-4CA-30, KSO-G02-9CA-30-EN, and KSO-G02-2NA-30-E are core models in the DAIKIN KSO series of solenoid pilot-operated directional control valves, G02 size (1/4 inch), with mounting pattern conforming to ISO 4401-03 / CETOP 3 / NG6 standards. The KSO series achieves an exceptional combination of 35 MPa high pressure and 100 L/min (G02 size) high flow capacity. Constructed from high-strength cast iron, the valve body delivers superior rigidity and fatigue resistance. The product is designed to IEC Pub529 IP65 dust and water-proof standards and complies with European CE safety regulations.
Spool Configuration by Model:
KSO-G02-2BB-30 (2-way, 2-position, spring offset) : A 2-way, 2-position direct-acting solenoid valve featuring spring offset construction with SOL.b solenoid. The spool returns to the initial position by spring force when de-energized, and shifts when energized. Ideal for simple on/off control and unloading circuits.
KSO-G02-4CA-30 (4-way, 3-position, spring centered) : A 4-way, 3-position solenoid directional valve featuring spring centered construction. The spool automatically returns to the neutral position by spring force when de-energized. Suitable for general actuator directional control with neutral blocking.
KSO-G02-9CA-30-EN (4-way, 3-position, A pressurized center) : A 4-way, 3-position solenoid directional valve with A port pressurized in the center position. This specialized center configuration suits specific hydraulic circuit requirements such as differential circuits or pre-pressurization functions. The EN suffix indicates built-in surge killer.
KSO-G02-2NA-30-E (2-way, 2-position, no-spring) : A 2-way, 2-position solenoid directional valve with no-spring construction. The spool position is maintained solely by the solenoid—does not automatically return when de-energized. The E suffix indicates DC24V with terminal box and indicator light.
As original DAIKIN KSO series solenoid valves, these products offer complete interchangeability within the same series and size, requiring no modifications to mounting interfaces or piping layouts.
Technical Specifications
KSO-G02 Series Common Specifications:
Brand: DAIKIN
Series: KSO Series
Nominal Size: G02 (1/4 inch)
Mounting Standard: ISO 4401-03 / CETOP 3 / NG6
Mounting Type: Gasket Mount
Maximum Operating Pressure: 35 MPa (350 kgf/cm²)
Note: Certain spool types (5C/66C/51C) have maximum operating pressure of 25 MPa (250 kgf/cm²)
Maximum Flow Rate: 100 L/min
Allowable Back Pressure: 17.5 MPa (175 kgf/cm²)
Maximum Shifting Frequency: 240 cycles/min
Protection Class: IEC Pub529 IP65
Insulation Class: Class B (Coil: Class H)
Dielectric Strength: AC1500V for 1 minute
Insulation Resistance: 50 MΩ minimum
Compatible Fluids: Petroleum-based hydraulic oil
KSO-G02-2BB-30 Specifications:
Model: KSO-G02-2BB-30
Spool Configuration: 2-way, 2-position
Spring Arrangement: Spring Offset
Voltage: AC200V (50/60Hz)
Starting Current: AC200V 50Hz: 1.21A / 60Hz: 1.07A
Holding Current: AC200V 50Hz: 0.26A / 60Hz: 0.19A
Holding Power: AC200V 50Hz: 21.5W / 60Hz: 18W
Permissible Voltage Fluctuation: AC200V 50Hz: 80–110% / 60Hz: 90–121%
Wiring: Terminal Box Type
Indicator Lamp: Equipped
Surge Killer: Not equipped
Operating Time: Energized 0.01–0.025s / Spring Return 0.01–0.045s
Weight: 1.5 kg
KSO-G02-4CA-30 Specifications:
Model: KSO-G02-4CA-30
Spool Configuration: 4-way, 3-position
Spring Arrangement: Spring Centered
Voltage: AC100V (50/60Hz)
Frequency: 50/60 Hz
Wiring: Terminal Box Type
Indicator Lamp: Equipped
Surge Killer: Not equipped
Weight: Approx. 1.5 kg
KSO-G02-9CA-30-EN Specifications:
Model: KSO-G02-9CA-30-EN
Spool Configuration: 4-way, 3-position
Center Function: A Port Pressurized in Center
Spring Arrangement: Spring Centered
Voltage: AC100V (50Hz) / AC100V (60Hz) / AC110V (60Hz)
Current: 0.44–0.51 A
Power Consumption: 21.5–22.5 W
Solenoid Configuration: Double Solenoid
Surge Killer: Equipped (EN suffix)
Wiring: Terminal Box Type
Weight: 1.8 kg
KSO-G02-2NA-30-E Specifications:
Model: KSO-G02-2NA-30-E
Spool Configuration: 2-way, 2-position
Spring Arrangement: No-Spring
Voltage: DC24V
Wiring: Terminal Box Type
Indicator Lamp: Equipped
Key Technical Advantages
1. High-Pressure High-Flow Performance
The KSO-G02 series delivers an exceptional combination of 35 MPa operating pressure and 100 L/min flow capacity. This performance places it at the forefront of NG6 size solenoid directional control valves, making it suitable for demanding high-pressure, high-flow hydraulic systems.
2. Rugged Environmental Protection
Designed to IEC Pub529 IP65 dust and water-proof standards, the valve features effective protection against dust ingress and water jets from any direction. CE compliance makes it suitable for export to European markets and equipment requiring CE certification.
3. High-Reliability Solenoid System
The solenoid coil utilizes Class H insulation material for excellent heat resistance. AC-powered models feature 80–121% voltage tolerance range. The solenoid supports continuous duty rating, ensuring long-term stable operation. Insulation resistance exceeds 50 MΩ with dielectric strength of AC1500V for 1 minute.
4. Precision Machining and Long Service Life
The valve body is manufactured from high-strength cast iron, with spool and bore surfaces precision-ground to ensure minimal internal leakage and long-term shifting accuracy. With a maximum shifting frequency of 240 cycles/min, the valve is ideal for high-cycle applications.
5. Flexible Spool Functions and Electrical Options
The KSO-G02 series offers a wide range of spool configurations—2-way 2-position (2BB/2NA), 4-way 3-position spring centered (4CA), 4-way 3-position A pressurized center (9CA), and more. Supports multiple voltage options including AC100V, AC200V, and DC24V. EN suffix models feature built-in surge killer to suppress interference with control circuits during valve switching.
6. Modular Stack Valve Compatibility
The KSO-G02 and KSO-G03 series support modular stack valve configurations. Allows flexible integration of throttle valves, check valves, pressure reducing valves, and other hydraulic components—significantly simplifying hydraulic system layout and reducing leakage risk.
Application Areas
KSO-G02-2BB-30 (2-way, 2-position, spring offset):
Unloading Circuits — System unloading and pressure release control
Hydraulic Cylinder Rapid Traverse — Oil circuit switching for differential circuits
Cooling and Filtration Circuits — On/off control for auxiliary oil circuits
Safety Interlock Devices — Emergency shutdown and safety valve control
KSO-G02-4CA-30 (4-way, 3-position, spring centered):
Injection Molding Machinery — Directional control for clamping, injection, and ejection cylinders
CNC Machine Tools — Directional control for machine tool hydraulic systems
Hydraulic Presses and Forging Equipment — Directional control for presses and forming equipment
Die-Casting Machines — Directional control for high-pressure casting equipment
General Industrial Hydraulic Systems — Standard 4-way, 3-position directional control
KSO-G02-9CA-30-EN (4-way, 3-position, A pressurized center):
Differential Hydraulic Circuits — Differential control requiring A-port pre-pressurization
Hydraulic Cylinder Floating Positioning — A-port pressure holding with B-port relief in neutral
Pre-Pressurization Control Systems — Specific hydraulic circuits requiring center pre-pressure
Specialized Hydraulic Equipment — Custom systems with specialized center function requirements
KSO-G02-2NA-30-E (2-way, 2-position, no-spring):
Actuator Position Holding — Applications requiring position maintenance when de-energized
Fixture and Jig Systems — Workpiece clamping state holding control
Safety Interlocks — Control circuits requiring safety state maintenance when de-energized
Memory Circuits — Hydraulic systems requiring retention of last operating state
Expert Maintenance Tips
1. Installation Guidelines
G02 size mounting surface must conform to ISO 4401-03 / CETOP 3 / NG6 standards. Use 4 M5×45 mounting bolts.
Thoroughly clean the mounting surface and all ports (P, A, B, T) before installation to prevent foreign particles from entering the valve and causing spool sticking or seal damage.
KSO-G02 and KSO-G03 series support modular stack valve configurations—pay attention to sealing and bolt length between stacked valve layers.
2. Hydraulic Fluid Cleanliness
Recommended fluid: Petroleum-based hydraulic oil. For water-glycol based fluids, verify seal material compatibility.
Note: Certain spool types (5C/66C/51C) have maximum operating pressure of 25 MPa (250 kgf/cm²), not 35 MPa. Confirm pressure rating with the complete model code.
Install a return line filter with minimum 25 μm filtration rating upstream of the valve.
3. Electrical Connection Specifications
KSO-G02-2BB-30 uses AC200V supply, with permissible voltage fluctuation: 50Hz 80–110% / 60Hz 90–121%.
KSO-G02-4CA-30 uses AC100V supply; KSO-G02-9CA-30-EN uses AC100V/AC110V supply.
KSO-G02-2NA-30-E uses DC24V supply.
KSO-G02-9CA-30-EN features built-in surge killer (EN suffix)—no additional surge suppressor required. For other models requiring surge suppression, optional configurations are available.
4. Back Pressure Control
5. Periodic Maintenance Inspection
Inspect the valve body for external oil leakage every 2,000 operating hours or at least annually.
Check electrical connectors/terminal boxes for looseness, oxidation, or moisture ingress.
If response lag or unstable shifting is observed, first check system fluid cleanliness and verify the spool is not sticking.
Indicator lamps (on terminal box models with indicators) help quickly verify solenoid energization status.
