Overview
IEC 62873-3-1:2020 is an IEC product-specific technical standard that defines particular requirements for residual current operated circuit-breakers (RCDs) and other devices equipped with screwless-type terminals for external copper conductors. This second edition updates the 2016 version and expands the scope to cover screwless-type terminals for rated currents up to 40 A, primarily suitable for connecting unprepared copper conductors up to 10 mm² cross-section. The document is intended to be applied together with the applicable RCD product standard rather than used alone.
Key topics and technical requirements
- Scope and applicability: Requirements apply to devices with screwless-type terminals for currents ≤ 40 A and conductors up to 10 mm²; the standard may be referenced by a range of product standards beyond RCDs.
- Terminal types and definitions: Defines terms such as universal terminal, non-universal terminal, push-wire terminal, clamping unit, and unprepared conductor.
- Marking and product information: Specifies marking rules for universal and non‑universal terminals (e.g., “sol”, “r”, “f”), insulation stripping length, and maximum number of conductors clamped.
- Construction and design requirements: Covers terminal design, dimensions of connectable conductors, connectable cross-sectional areas, insertion and withdrawal procedures, and resistance to ageing.
- Testing and reliability: Includes mandatory tests for terminals such as mechanical strength, cycling tests, reliability of screwless systems and connections, and pull force testing (see Tables 1–4 for conductor sizes and test arrangements).
- Compatibility with product standards: Intended to be referenced by RCD product standards (e.g., IEC 61008, IEC 61009) and other device standards.
Significant technical changes in the 2020 edition:
- Scope extended to screwless-type terminals up to 40 A
- Scope broadened to address other devices in addition to RCDs
- Table updates to reflect rated currents up to 40 A
- Clause changes (8.1 and 9.1) to allow wider reference by other product standards
Practical applications
- Guidance for manufacturers designing RCDs, RCBOs or similar devices with screwless terminals
- Requirements for product test labs and certification bodies performing terminal reliability and mechanical tests
- Reference for standards writers integrating terminal requirements into other product standards
- Useful to design engineers and technical specifiers verifying connector compatibility with solid or stranded copper conductors and installation instructions
Who should use this standard
- Electrical equipment manufacturers and designers
- Compliance and regulatory teams
- Test laboratories and certification bodies
- Standards committees and product specifiers
- Installers seeking to understand marking and conductor preparation requirements
Related standards
Keywords: IEC 62873-3-1:2020, screwless-type terminals, residual current operated circuit-breakers, RCDs, copper conductors, up to 40 A, terminal reliability, IEC 61008, IEC 61009.