ISO 14617-4:2002

Overview

ISO 14617-4:2002 - "Graphical symbols for diagrams - Part 4: Actuators and related devices" defines a harmonized set of graphical symbols for actuators and actuating devices used in technical diagrams. As part of the ISO 14617 series, it provides symbol definitions, application rules and illustrative examples for basic actuator elements, manually operated actuators, automatic actuators and composite actuating devices. The standard supports consistent symbol use across process plant documentation, control schematics and technical drawings.

Key topics and requirements

• Scope and purpose: Specifies graphical symbols for basic elements in actuators, complete actuators and actuating devices in diagrams. It does not replace rules in ISO 81714‑1 or the overview/index functions of ISO 14617‑1.
• Terms and definitions: Defines core terms such as actuator, actuating device, manual actuator, automatic actuator, detent, latching, interlocking and trip‑free device to ensure consistent interpretation.
• Symbol sets:
  • Basic elements (gears, clutches, brakes, springs, delay and return devices, detents, latches, interlocks, trip‑free mechanisms).
  • Manually operated actuators (push, pull, turn, lever, pedal, key, removable handle) and associated application rules.
  • Automatic actuators and multi‑component actuating devices (symbols for combined motor, contacts, transducers, etc.).
• Application rules and examples: Guidance on positioning, connection points, use of supplementary symbols (position indicators, return/detent markers), and examples showing composite devices (relays, solenoid clutches, spring‑return valves).
• Normative references and registration: Cross‑references to ISO 14617‑1, ‑2, ‑7, ‑8 and ISO 81714‑1 for general rules, indexes and presentation requirements; notes about possible patent claims and IEC collaboration.

Applications and users

ISO 14617-4 is practical for:

• Control system engineers and process designers creating P&IDs, control schematics and actuator diagrams.
• Technical drafters and CAD specialists standardizing symbol libraries for documentation and manuals.
• Manufacturers of valves, actuators and electro‑mechanical equipment who need consistent symbol representation.
• Maintenance teams and safety engineers who rely on clear diagrams for troubleshooting and compliance. Benefits include improved clarity, interoperability of diagrams across organizations, reduced ambiguity in installation and maintenance documentation, and support for regulatory and safety reporting.

Related standards

• ISO 14617-1: General information and indexes
• ISO 14617-2: Symbols having general application
• ISO 14617-7: Basic mechanical components
• ISO 14617-8: Valves and dampers
• ISO 81714-1: Design rules for graphical symbols in technical documentation

Keywords: ISO 14617-4, graphical symbols, actuators, actuating devices, technical diagrams, P&ID, process plant documentation.