IEC 60335-2-26:2024

Overview - IEC 60335-2-26:2024 (Clocks safety)

IEC 60335-2-26:2024 is the fifth edition of the IEC safety standard that specifies particular requirements for the safety of household and similar electrical clocks rated up to 250 V (including DC and battery-operated appliances). It covers common hazards encountered in and around the home for devices such as alarm clocks, electrically wound spring clocks, and clocks driven by mechanisms other than motors. This edition is a technical revision that replaces the 2002 edition and Amendment 1 (2008) and is intended to be used together with the latest IEC 60335-1 general requirements.

Key topics and technical requirements

• Scope and exclusions: Applies to mains- and battery-powered domestic clocks; excludes industrial clocks, watches, clocking‑in systems, clocks with additional appliance-control functions (e.g., timers for cookers or washing machines), and devices solely with electronic circuits covered by IEC 60065 / IEC 62368‑1.
• Alignment with IEC 60335-1: Updated to conform with the 2020 edition of IEC 60335-1 for harmonized general safety requirements.
• Temperature and heating: Introduces limits on the temperature rise of externally accessible surfaces to reduce burn risks.
• Electrical safety tests: Requirements and test procedures for leakage current, electric strength, transient overvoltages, and insulation (see multiple test circuits and diagrams).
• Mechanical and stability tests: Protection against mechanical hazards, small parts, stability and robustness under normal and abnormal operation.
• Battery and charging safety: Normative Annex B covers battery-operated appliances, separable and detachable batteries, and safe charging considerations.
• Components and construction: Rules for internal wiring, components, switches, transformers, clearances/creepage distances, and resistance to heat, fire and rusting.
• Test details and annexes: Extensive annexes include motor ageing, switch/transformer tests, software evaluation (Annex R), UV‑C effects, and guidance for measurement methods.

Practical applications - who uses this standard

• Manufacturers and designers of electric and battery-operated clocks for product design, risk assessment and safe component selection.
• Test laboratories and certification bodies performing safety testing and conformity assessment to achieve market access and CE/IEC compliance.
• Regulatory and compliance teams ensuring products meet international safety requirements.
• R&D and quality assurance teams applying temperature, leakage and mechanical test regimes during development and production.

Related standards and notes

• Use in conjunction with IEC 60335-1 (general requirements).
• Clocks that are electronic-only may be covered by IEC 60065 or IEC 62368‑1.
• National health, labour and transport authorities may require additional country-specific rules for vehicle, ship or aircraft use.

Keywords: IEC 60335-2-26:2024, clock safety standard, household electrical appliances, alarm clocks, battery-operated clocks, IEC 60335-1, temperature rise limits, leakage current, product compliance.