Overview
IEC 62873-3-1:2016 specifies particular requirements for residual current operated circuit-breakers (RCDs) equipped with screwless-type terminals intended for household and similar use. It applies to RCDs with current not exceeding 20 A (note: some countries limit this to 16 A) that are primarily suitable for connecting unprepared copper conductors up to 4 mm² cross-section. This part is supplementary and must be applied together with an RCD product standard (for example IEC 61008-1 or IEC 61009-1).
Key Topics
- Scope & applicability
- RCDs with screwless terminals for external copper conductors; for currents ≤ 20 A and nominal conductor cross-sections up to 4 mm².
- Terminal types and definitions
- Universal terminals (accept rigid and flexible conductors), non-universal terminals, push‑wire terminals, and the concept of unprepared conductors.
- Design and construction requirements
- Individual clamping of each conductor, prevention of inadequate insertion, ability to clamp multiple conductors up to manufacturer’s declared maximum.
- Marking and user information
- Terminals declared for flexible conductors must be marked with "f"; insulation stripping length must be indicated; manufacturer to state maximum number of conductors.
- Connectable conductors and cross-sections
- Tables define allowable conductor diameters and nominal cross-sections by rated current (e.g., up to 2.5 mm² for lower-rated devices, up to 4 mm² for devices above 13 A).
- Reliability and test requirements
- Mandatory tests include reliability of screwless systems, connection reliability, mechanical strength, and cycling tests (see clauses 9.2 and 9.3). Compliance is verified by inspection and testing.
Applications and Who Uses It
- Manufacturers designing RCDs with screwless terminals to meet international safety and performance requirements.
- Product designers and engineers specifying terminal types, conductor compatibility, and marking details.
- Test laboratories and certification bodies performing the mechanical, cycling and reliability tests required for conformity assessment.
- Electrical specifiers and installers selecting compliant RCDs for household and similar installations where screwless connections are preferred.
Practical uses include product development, conformity assessment, technical specifications for procurement, and ensuring safe, reliable connections for unprepared copper conductors in domestic electrical installations.
Related Standards
- IEC 61008-1 - RCCBs (RCDs without integral overcurrent protection) - general rules
- IEC 61009-1 - RCBOs (RCDs with integral overcurrent protection) - general rules
- IEC 62873-2 - RCD vocabulary (terms and definitions)
Keywords: IEC 62873-3-1, RCD, residual current operated circuit-breaker, screwless terminals, push-wire terminal, unprepared copper conductors, household electrical safety, terminal reliability testing.