ISO 7400:1990

Overview

ISO 7400:1990 - "Mopeds - Alternating current flasher units" - is the second edition (1990) international standard that specifies the electrical characteristics and type‑testing requirements for alternating‑current (a.c.) flasher units intended for mopeds. It replaces ISO 7400:1984 and applies to flashers designed for 6 V or 12 V electrical systems, for both simultaneous and alternating flashing arrangements.

Key topics and technical requirements

The standard focuses on electrical performance, marking, and environmental/mechanical durability tests. Important technical topics include:

• Scope and identification

  • Mandatory legible marking: manufacturer trade name/mark, rated voltage, short‑circuit current (Zcc), terminal identification and lamp wattages.
  • Applies to flasher units for mopeds (per ISO 3833).

• Electrical test conditions

  • Test supply: alternating current at 50 Hz or 60 Hz.
  • Working voltages for type tests:
    • 6 V systems: tests at specified r.m.s. voltages (see standard).
    • 12 V systems: tests at corresponding r.m.s. voltages.
  • Filament lamp requirements reference IEC 810.

• Performance criteria

  • Flash‑rate and current “on”‑time requirements, measured after stabilization and defined cycles.
  • Starting time and timing tolerances for first on/off events.
  • Tell‑tale (indicator) behavior: must operate in phase or counterphase and indicate lamp failure by ceasing or changing frequency.

• Electrical resilience

  • Voltage drop limits between input/output terminals (specified maximum).
  • Dielectric strength: withstand 1 min at 1 000 V r.m.s. between terminals and exposed metallic parts.
  • Overload strength and short‑circuit current capability (Zcc defined in the standard related to lamp wattage and nominal voltage).

• Environmental and mechanical tests

  • Temperature and humidity resistance: tests at elevated humidity, high and low temperatures (e.g., +40 °C/90–95% RH, +80 °C, −40 °C).
  • Vibration tests: sinusoidal 20–200 Hz, acceleration ~50 m/s²; endurance over axes.
  • Impact test: pendulum strike arrangement (500 mm wire, 25 kg block).
  • Endurance: long‑term cycling (e.g., 100 h of 15 s on/15 s off or 50 h continuous).

• Sampling and sequence

  • Typical sample size: 20 units with a prescribed sequence of individual tests.

Applications - who uses ISO 7400:1990

• Moped component manufacturers and flasher‑unit designers for product development and type‑approval.
• Test laboratories and vehicle homologation authorities conducting type‑testing and regulatory compliance.
• Quality assurance and supplier engineers for production verification and durability testing.
• Vehicle manufacturers integrating flasher units into electrical systems (6 V / 12 V).

Related standards

• ISO 3833 - Road vehicles: terms and definitions
• IEC 810 - Lamps for road vehicles (filament lamp performance)
• ISO 7398 / ISO 7399 / ISO 8052 - Related motorcycle and moped flasher unit standards

Keywords: ISO 7400:1990, mopeds, alternating current flasher units, flasher type‑testing, 6 V, 12 V, flash‑rate, dielectric strength, vibration test, ISO standards.