YUKEN EDS series direct-acting servo valve
YUKEN EDS Series Direct-Acting Servo Valve Model and Parameters
1. Model Designation
The complete model format of YUKEN EDS series direct-acting servo valve is: EDS-01-B-EH-50. Each segment of the model has a specific meaning, as detailed below:
| Model Segment | Description |
| F- | Special seals for phosphate ester type fluid (omit if not required) |
| EDS | Direct-acting electro-hydraulic servo valve (series code) |
| -01/-02 | Valve size: 01 (small flow), 02 (medium flow), suitable for direct-acting structure |
| -B/-C/-H | Pressure range: B (0.3-6.9 MPa / 44-1000 psi), C (0.5-15.7 MPa / 72-2275 psi), H (0.8-24.5 MPa / 116-3550 psi) |
| -EH/-N | Control mode: EH (integrated amplifier), N (external amplifier) |
| -50/-51 | Design number (50: standard type, 51: enhanced anti-pollution type) |
| -S/-L | Position feedback type: S (potentiometer feedback), L (inductive feedback, omit if standard) |
2. Technical Specifications (Taking EDS-01 as an Example)
| Specification Item | Value |
| Maximum Operating Pressure | 24.5 MPa (3550 psi) |
| Rated Flow Rate | 10 L/min (2.64 U.S. gpm) |
| Minimum Flow Rate | 0.2 L/min (0.05 U.S. gpm) |
| Hysteresis | ±0.3% or less (under rated conditions, superior to proportional valves) |
| Repeatability | ±0.1% or less (tested at 25℃ ambient temperature) |
| Frequency Response | 80 Hz (-90 degree), 150 Hz (-3 dB) (advantage of direct-acting structure) |
| Supply Electric Power | 24 V DC (18 to 30 V DC, including ripple) |
| Maximum Power Input | 30 W (for EH type with integrated amplifier) |
| Input Signal | 4-20 mA DC or 0-10 V DC (selectable via wiring) |
| Input Impedance | 250 Ω (for 4-20 mA), 10 kΩ (for 0-10 V DC) |
| Position Feedback Signal | 4-20 mA DC (corresponding to 0-100% valve opening) |
| Ambient Temperature | -20 – 80 °C (-4 – 176 °F) (with circulated air) |
| Oil Cleanliness Requirement | NAS 6 class or higher (higher requirement due to direct-acting precision structure) |
| Coil Resistance | 12 Ω (at 25℃ ambient temperature) |
3. Product Overview
YUKEN EDS servo valve, featuring a compact direct-acting structure that eliminates the need for intermediate pilot stages, enabling faster response speed and higher control accuracy. It is specially developed for hydraulic systems that require rapid dynamic response and precise flow/pressure regulation, and can realize continuous stepless adjustment of fluid flow or pressure according to the input electrical signal. The valve is characterized by ultra-low hysteresis, excellent repeatability, compact size and reliable operation, making it widely used in precision positioning systems, servo hydraulic presses, high-speed testing equipment, and other industrial fields that demand high dynamic performance and control precision. It can be seamlessly connected with PLC, CNC and other control systems to realize intelligent and automated control of the hydraulic system, and its direct-acting structure also reduces energy consumption and maintenance costs compared with pilot-type servo valves.
