Overview - ISO 10770-3:2020 (Electrically modulated hydraulic control valves, Part 3)
ISO 10770-3:2020 is an international standard in the hydraulic fluid power family that defines test methods for electrically modulated hydraulic pressure control valves. It describes how to determine the performance characteristics of devices such as electrically modulated relief valves and reducing valves, with the goal of producing repeatable, comparable data for system design, production acceptance and type testing.
Key topics and technical requirements
This part of ISO 10770 focuses on the measurements, test setups and reporting needed to characterise pressure control valves. Major technical topics include:
- Standard test conditions and test installation - guidance on test rig configuration and controlled-pressure volumes to ensure comparable results.
- Instrument accuracy and dynamic range - requirements for measuring equipment and uncertainty considerations.
- Electrical tests for valves without integrated electronics - e.g., coil resistance (cold and hot) and optional coil inductance checks.
- Steady‑state tests for relief and reducing valves:
- Proof pressure (optional)
- Internal leakage
- Valve-controlled pressure vs input signal (with constant flow)
- Threshold and head-loss (pressure vs flow) characteristics
- Effect of fluid temperature on controlled pressure
- Dynamic tests:
- Step response to changes in input signal and flow
- Frequency response testing
- Specific dynamic test circuits and measurement points
- Pressure impulse test and presentation of results - standardized formats for test reports, production acceptance and type test documentation.
- Terms, definitions and symbols to harmonize vocabulary (references ISO 5598 and related normative documents).
Practical applications and users
ISO 10770-3 is practical for anyone involved in design, testing, procurement or maintenance of electro-hydraulic systems:
- Valve manufacturers - to validate performance, demonstrate compliance, and support product datasheets.
- Test laboratories and quality assurance teams - to run production acceptance tests and type tests using standardized methods.
- System designers and OEMs - to select valves based on reliable, comparable performance data for hydraulic systems.
- Certification bodies and specifiers - to evaluate product claims and ensure interoperability and safety.
Benefits include improved test uniformity, reproducible performance data for system modelling, and clearer communication of valve characteristics (e.g., pressure gain, hysteresis, threshold).
Related standards
- ISO 10770 series (other parts addressing electrically modulated hydraulic control valves)
- ISO 5598 (vocabulary for fluid power)
- ISO 3448 (viscosity classification), ISO 4406 (contamination coding)
- ISO 9110-1 (measurement principles), ISO 10771-1 (fatigue pressure testing)
Keywords: ISO 10770-3, electrically modulated hydraulic control valves, pressure control valves, test methods, hydraulic fluid power, relief valve testing, reducing valve testing, valve performance characterization.