ISO 14617-6:2002

Overview

ISO 14617-6:2002 - Graphical symbols for diagrams - Part 6: Measurement and control functions - defines standardized graphical symbols and application rules for representing measurement and control functions in technical diagrams. It is part of the ISO 14617 series that provides a harmonized library of symbols for process and product documentation. Symbols in this part can represent functions in diagrams or, in simpler applications, stand for the devices or components that implement those functions.

Key Topics

• Scope and purpose: Standardizes symbols for measurement and control functions used in control diagrams and process documentation.
• Terms and definitions: Clarifies control terminology (e.g., control, operation, automatic, final controlling element, delay device, detent, latching, interlocking).
• Functional links and junctions: Rules for drawing functional connections, joints, and direction of signal or energy flow.
• Point of measurement: Symbol conventions (e.g., symbol 1011) and when to indicate measurement locations explicitly.
• Operation of final controlling elements: Symbols for manual and automatic operation (e.g., 1021, 1022), inputs (analog/binary), and rules for signal designation.
• Auxiliary symbols: Delay devices (651–653), automatic return (654), detents (655, 659), latching (661), blocking (664), interlocking (666).
• Information-processing and logic functions: Coverage includes information processing, binary logic, back-up functions and practical application examples (see clause 10).
• Application rules and examples: Clear guidance on placement, sizing (e.g., dot diameter for joints), and examples of symbol use in control loops.

Applications and Who Uses It

ISO 14617-6 is used to create consistent, legible control and instrumentation diagrams (P&IDs), schematics, and technical drawings across industries:

• Process plant engineers and instrumentation & control (I&C) designers
• CAD technicians and technical illustrators producing P&IDs and control diagrams
• Standards writers and technical documentation teams seeking harmonized symbol libraries
• Automation and control system integrators documenting control logic and final controlling elements

Practical benefits include improved interoperability of documentation, easier maintenance and commissioning, and clearer communication between multidisciplinary teams.

Related Standards

• ISO 14617 series (Parts 1–12, 15) - broader symbol library for diagrams
• ISO 14617-5 - symbols for measurement and control components/devices
• ISO 81714-1 - rules for designing graphical symbols
• IEC 60617 and IEC 61175 - complementary electrical and signal designation standards

Keywords: ISO 14617-6:2002, graphical symbols for diagrams, measurement and control functions, control diagrams, P&ID symbols, final controlling element, functional connection.