ISO 25197:2020

Overview

ISO 25197:2020 - Small craft - Electrical/electronic control systems for steering, shift and throttle - defines requirements for the design, construction and testing of electrical/electronic steering, shift and throttle systems and dynamic-positioning systems (DPS) on small craft up to 24 m length of hull. The standard covers whole-system components (input devices, CPUs, harnesses, actuators) and excludes electric trolling motors and autopilot systems on sailing craft.

Key topics and technical requirements

• System coverage: Electrical and electronic steering, combined or separate shift and throttle systems, joystick controls and DPS functionality.
• Components and interfaces: Control heads, command-station transfer, portable helm station controls, actuators and wiring harnesses.
• Failure modes and responses: Requirements for loss of operation, loss of computer command logic, fail‑safe modes and alarm policies.
• Testing requirements:
  • Functional tests for steering, control levers (shift/throttle) and joysticks (including operational/durability tests).
  • Extensive environmental testing: salt mist, damp heat (cyclic and steady state), high/low temperature (operation and storage), immersion considerations, UV exposure.
  • Mechanical robustness: vibration, shock, drop tests.
  • Electromagnetic compatibility (EMC): immunity to radiated/conducted RF, fast transients (bursts), surges, ESD, power supply variation; radiated and conducted emissions requirements.
  • Electrical safety checks: insulation resistance and compass safe distance evaluations.
• Marking and documentation: Labelling requirements and mandatory owner’s manual instructions for safe operation and maintenance.

Practical applications and who uses it

ISO 25197:2020 is used to:

• Guide marine electronics manufacturers in product design and certification of electronic steering, throttle and shift systems.
• Define test programs for independent test labs and shipyards when validating control systems and DPS installations on small craft.
• Support system integrators and OEMs in ensuring interoperability, durability and EMC compliance.
• Inform regulatory bodies, classification societies and procurement teams assessing equipment suitability for recreational and commercial small craft.
• Help owners/operators understand required labelling and manual information for safe operation.

Related standards

ISO 25197 references and aligns with several marine and IEC/ISO documents for testing and environmental conditions, including but not limited to ISO 8846, ISO 10133, ISO 11591, IEC 60945 and multiple IEC/ISO tests for EMC, salt mist and climatic/mechanical loads.

Keywords: ISO 25197:2020, small craft electrical control systems, steering shift throttle, dynamic positioning, EMC testing, environmental testing, joystick durability, fail-safe marine controls.