EN IEC 60445:2021

• Abstract:

  IEC 60445:2021 is available as IEC 60445:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60445:2021 applies to the identification and marking of terminals of electrical equipment such as resistors, fuses, relays, contactors, transformers, rotating machines and, wherever applicable, to combinations of such equipment (e.g. assemblies), and also applies to the identification of terminations of certain designated conductors. It also provides general rules for the use of certain colours or alphanumeric notations to identify conductors with the aim of avoiding ambiguity and ensuring safe operation. These conductor colours or alphanumeric notations are intended to be applied in cables or cores, busbars, electrical equipment and installations. This basic safety publication is primarily intended for use by technical committees in the preparation of standards in accordance with the principles laid down in IEC Guide 104 and ISO/IEC Guide 51. It has the status of a basic safety publication in accordance with IEC Guide 104. IEC 60445:2021 cancels and replaces the sixth edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) the definitions have been aligned with IEC 60050-195:2021 and IEC 60050-826; b) the provisions for colour to be used for identification of certain designated conductors are made requirements and not only recommendations; c) introduction of a new subclause on marking of protective terminals for multiple power supply inputs on equipment.

• Status: Published
• Publication Date: 02-Sep-2021
• ICS: 01.080.20 - Graphical symbols for use on specific equipment
• ICS: 13.110 - Safety of machinery
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: CLC/SR 3 - Information structures, documentation and graphical symbols
• Drafting Committee: IEC/TC 3 - IEC_TC_3
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 02-Feb-2026
• Completion Date: 25-Aug-2026
• Ref Project: SIST EN IEC 60445:2021 - Basic and safety principles for man-machine interface, marking and identification - Identification of equipment terminals, conductor terminations and conductors (IEC 60445:2021)

• Replaces: EN 60445:2017 - Basic and safety principles for man-machine interface, marking and identification - Identification of equipment terminals, conductor terminations and conductors
• Effective Date: 07-Sep-2021
• Refers: EN 60417-2:1999 - Graphical symbols for use on equipment - Part 2: Symbol originals
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60034-8:2026 - Rotating electrical machines - Part 8: Terminal markings and direction of rotation
• Effective Date: 18-Aug-2026
• Referred By: EN 60601-1:2006/A1:2013 - Medical electrical equipment - Part 1: General requirements for basic safety and essential performance
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 61496-1:2020 - Safety of machinery - Electro-sensitive protective equipment - Part 1: General requirements and tests
• Effective Date: 03-Feb-2026
• Referred By: EN 50171:2021 - Central safety power supply systems
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60947-4-2:2023 - Low-voltage switchgear and controlgear - Part 4-2: Contactors and motor-starters - Semiconductor motor controllers, starters and soft-starters
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60204-32:2025 - Safety of machinery - Electrical equipment of machines - Part 32: Requirements for hoisting machines
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60947-4-2:2023/A1:2024 - Low-voltage switchgear and controlgear - Part 4-2: Contactors and motor-starters - Semiconductor motor controllers, starters and soft-starters
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60669-2-3:2025 - Switches for household and similar fixed electrical installations - Part 2-3: Particular requirements - Time-delay switches (TDS)
• Effective Date: 03-Feb-2026
• Referred By: EN 62135-1:2015 - Resistance welding equipment - Part 1: Safety requirements for design, manufacture and installation
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60034-33:2022 - Rotating electrical machines - Part 33: Synchronous hydrogenerators including motor-generators - Specific requirements
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60947-8:2023 - Low-voltage switchgear and controlgear - Part 8: Control units for built-in thermal protection (PTC) for rotating electrical machines
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60974-1:2022 - Arc welding equipment - Part 1: Welding power sources
• Effective Date: 03-Feb-2026
• Referred By: EN IEC 60947-4-3:2024 - Low-voltage switchgear and controlgear - Part 4-3: Contactors and motor-starters - Semiconductor controllers and semiconductor contactors for non-motor loads
• Effective Date: 03-Feb-2026

Overview

EN IEC 60445:2021 (IEC 60445:2021) is a basic safety publication that defines principles for the marking and identification of electrical equipment terminals, conductor terminations and conductors. This 7th edition supersedes the 2017 edition and is published by CLC/CENELEC as a European adoption of the IEC International Standard. The document is available as a Redline (RLV) version showing technical changes from the previous edition.

Key topics and requirements

• Scope of application: Identification and marking of terminals on equipment such as resistors, fuses, relays, contactors, transformers, rotating machines and assemblies; and identification of terminations of certain designated conductors.
• Methods of identification: Use of colours, bi‑colour combinations, alphanumeric notations and graphical symbols for consistent terminal and conductor identification.
• Colour identification: Detailed rules for application of single colours (e.g., GREEN, YELLOW), bi‑colour combinations and permitted colour pairs for specific conductor types.
• Designated conductors covered: Neutral/mid‑point conductors, line conductors (AC and DC), protective conductor, PEN/PEL/PEM variants, functional earthing and bonding conductors, and system‑referencing conductors.
• Marking of terminals: Principles for terminal identification on single‑ and multi‑terminal elements, groups of elements and multi‑input equipment. New subclause addressing marking of protective terminals for multiple power‑supply inputs on equipment.
• Mandatory provisions: Colour provisions for certain designated conductors have been elevated from recommendations to requirements in this edition.
• Alignment with terminology: Definitions aligned with IEC 60050‑195:2021 and IEC 60050‑826 to harmonize language and reduce ambiguity.
• Annexes: Informative annexes include tables of colours/alphanumeric notations and notes on national deviations (Annex B).

Practical applications and users

EN IEC 60445:2021 is used to achieve unambiguous, safe identification across electrical equipment and installations. Typical users:

• Manufacturers of electrical equipment and rotating machines (labeling terminals and internal wiring)
• Panel builders and switchgear designers (terminal marking and wiring diagrams)
• Machine designers and OEMs integrating multiple power inputs
• Electrical installers, maintenance and safety engineers (identifying conductors and terminations)
• Standards and technical committees preparing related normative documents

Benefits include improved safety, easier maintenance and commissioning, reduced wiring errors and enhanced cross‑border harmonization.

Related standards

• IEC 60050 series (electrotechnical vocabulary / definitions)
• IEC 60417 (graphical symbols for use on equipment)
• IEC 60617 (graphical symbols for diagrams)
• IEC Guide 104 (principles for basic safety publications)

Keywords: EN IEC 60445:2021, identification of equipment terminals, conductor identification, marking, conductor colours, alphanumeric notation, protective conductor, terminal marking, man‑machine interface.