Description
The Domin S4 Pro is the world’s smallest direct-drive servo valve. With a connection circle of just 12.2 mm and a weight of 290 g, it delivers the dynamics and precision of two-stage servo valves – whilst requiring significantly less maintenance and without the need for external amplifier electronics. Typical applications include robotics, motorsport, aerospace, simulation and compact industrial automation.
Technical highlights
- The world’s smallest direct-drive servo valve (ISO 10372 size 01)
- Integrated on-board electronics with slide position feedback – no external amplifier required
- Response time under 3 ms, frequency response above 200 Hz (–90° phase)
- Hysteresis, threshold and zero-point offset: all less than 1 per cent
- Maximum operating pressure 350 bar (5,000 psi)
- Nominal flow rate 0.5 to 18 l/min (rated at 35 bar ΔP per control edge)
- Power consumption less than 2 W, supply voltage 22–30 V DC
- Vibration resistance: 35 g (3 axes), shock resistance: 50 g
- Choice of three seal materials: nitrile, Viton, FFKM
- Mounting interface ISO 10372-01-01, tightening torque 2.5 Nm
Order code: S4 Pro – [1] – [2] – [3] – [4] – [5] – [6] – [7] – [8] – [Custom ID]
Example: S4 Pro – 6 – A – A – C – E – N – R – N
= 6 l/min · Axis Cut · ±10 V · centre position · 6+PE round plug · no enable · standard oil · nitrile
| Position | Description | Options |
|---|---|---|
| [1] | Nominal flow rate | 0.5 to 18 l/min (any value, rated at 35 bar ΔP) – suffix R for reversed A/B connections (e.g. 18R) |
| [2] | Valve overlap | A – Axis Cut (0% overlap, linear response curve) D – Deadband (±10% deadband, no flow in the zero range) O – Overlap (±3% overlap, 50% gain at the centre) X – Special version available on request |
| [3] | Control signal | A – ±10 V | B – ±20 mA | C – 4–20 mA | D – ±5 V | E – ±5 mA | F – ±10 mA | G – ±50 mA | H – ±40 mA | I – ±25 mA | X – Special Combined input/output possible (e.g. AC = ±10 V input, 4–20 mA output) |
| [4] | De-energised position | C – Centre position (valve returns passively to the neutral position) X – Special version available on request |
| [5] | Electrical plug | B4 – Flying lead, 4-wire, 300 mm (White = 0 V, Black = +24 V, Green = Input−, Red = Input+) E – 6+PE circular connector, EN 175201-804 / MIL 5015, housing size 14 E4 – 4-pin circular connector, EN 175201-804 / MIL 5015, housing size 14 G – Winchester G4-20P rack-and-panel X – Special version on request |
| [6] | Enable function | N – No enable function Y – Enable mode via voltage input (Drive ON: 9–30 V / Drive OFF: 0–5 V; only with connector E) |
| [7] | Hydraulic fluid | R – Hydraulic oil in accordance with DIN 51524, filtered to ISO 4406 18/16/13 X – Special version available on request |
| [8] | Sealing material | N – Nitrile NBR (Shore 90) – standard for mineral oils V – Viton FKM (Shore 85) – increased resistance to high temperatures and chemicals F – FFKM (Shore 75) – highest chemical resistance X – special version available on request |
Data sheet: https://domin.com/datasheet/s4-pro





