Overview
ISO 6742-4:2023 - Cycles: Lighting systems powered by the cycle’s movement specifies performance requirements and test methods for cycle lighting systems that derive power from the bicycle’s movement (e.g., dynamos/generators). It applies to cycles intended for use on public roads - especially bicycles complying with ISO 4210 and ISO 8098 - and to lighting and signalling devices conforming to ISO 6742‑1. The standard covers both interchangeable (“open”) and integrated (“closed”) lamp‑and‑power combinations.
Key topics and technical requirements
- Scope & system types: Defines open systems (interchangeable lamps and generators) and closed systems (integrated or manufacturer‑specified combinations).
- General durability tests: Mandatory corrosion (see Clause 7.1 / ISO 9227 salt spray) and water‑resistance tests (Clause 7.2 / IEC 60529 IP concepts).
- Front and rear lamp requirements: Front lamps must meet photometric and electrical criteria from ISO 6742‑1 and pass open/closed system tests; rear lamps have separate power and photometric limits.
- Generator types: Distinguishes frictional‑drive and positive‑drive generators and sets electrical/efficiency characteristics and test regimes (Clause 5.4 and 7.5).
- Electrical performance and protections:
- Lighting evaluation at the specified test voltage; voltage‑limiting measures only activate above test voltage.
- Nominal lamp voltage must match system voltage or use appropriate electronic ballast.
- Limits on power consumption (e.g., front lamp consumption requirement and rear lamp ≤ 0.6 W at test voltage).
- Stand/parking light behaviour: Integrated capacitors are allowed but must meet charging characteristics and generator voltage reduction limits (specified % reductions at 15 s, 30 s, 60 s, 90 s, 120 s). Stand lights must emit visible light for at least 240 s.
- Test methods & verification: Includes power measurement, high‑speed endurance, and specific tests for frictional and positive drive generators (Clauses 7.3–7.6). Annex A covers electronic loads for LED generator measurement; Annex B covers efficiency calculations; Annex C provides load verification guidance.
- Marking & instructions: Manufacturer marking, durability tests and user instructions are specified.
Applications and who uses this standard
- Bicycle manufacturers and OEMs designing hub or bottle dynamos and integrated lighting systems.
- Lighting component suppliers and LED lamp designers validating compatibility in open systems.
- Test laboratories performing conformity, photometric and electrical endurance testing.
- Product certification bodies, procurement teams, and regulators requiring compliance for road‑use bicycles.
- Safety engineers and fleet managers specifying robust, road‑legal bicycle lighting.
Related standards
Keywords: ISO 6742-4:2023, cycle lighting standard, bicycle dynamo, generator testing, open system, closed system, LED generator, corrosion resistance, water resistance, photometric performance.