ISO 8820-6:2019

Overview

ISO 8820-6:2019 - "Road vehicles - Fuse-links - Part 6: Single-bolt fuse-links" defines the design, test procedures, performance requirements and dimensions for single-bolt fuse-links used in road vehicles. This second edition (2019) replaces the 2007 edition and applies to fuse-links with a rated voltage of 58 V, current ratings ≤ 300 A, and a breaking capacity of 2 000 A, intended for use in nominal vehicle voltages of 12 V, 24 V and/or 48 V.

Key topics and technical requirements

• Scope & compatibility
  • Intended to be used in conjunction with ISO 8820-1 (definitions and general test requirements) and ISO 8820-2 where relevant.
• Rated values
  • Rated voltage: 58 V; current ratings listed (30, 40, 50, 75, 100, 125, 150, 175, 200, 225, 250, 300 A).
  • Breaking capacity: 2 000 A.
• Mechanical & electrical design
  • Definition of an insulating nut and requirements for terminal finishes and corrosion protection.
  • Mounting torque specified at (12 ± 1) Nm.
  • Insulating nut insulation resistance ≥ 200 kΩ (measured at 100 V DC).
• Test procedures & performance
  • Test sequence and grouping across mechanical, electrical and environmental tests (minimum sample groups of 10).
  • Voltage drop limits specified per fuse rating (e.g., 30 A → max 120 mV; 300 A → max 70 mV).
  • Operating time ratings with defined limits at multiple multiples of In (1.0 I, 1.35 I, 1.5 I, 2.0 I, 3.5 I, 6.0 I).
  • Transient current cycling performed at (90 ± 5) °C with defined on-time/current profiles.
  • Breaking capacity test at 2 000 A using specified test cable sizes (per ISO 6722-1 conductor guidance).
  • Strength tests for insulating body and insulating nut - components must remain physically intact after mechanical stress.
• Test fixtures & dimensions
  • Detailed test-fixture specifications, cable-size tables and dimension drawings are provided to ensure repeatable test conditions.

Applications

• Ensures reliable short-circuit and overload protection for electrical distribution in passenger cars, light and heavy commercial vehicles, and electrical subsystems operating at 12 V, 24 V or 48 V.
• Used for component specification, vendor qualification, type testing, and compliance verification in vehicle electrical system design and manufacturing.

Who should use this standard

• Automotive OEMs and Tier‑1/Tier‑2 suppliers (fuse and connector manufacturers)
• Electrical and systems engineers designing vehicle power distribution
• Test laboratories and conformity assessment bodies
• Regulatory and procurement teams specifying protective devices

Related standards

• ISO 8820-1 (Definitions and general test requirements)
• ISO 8820-2
• ISO 6722-1 (Vehicle single-core cable requirements)
• ISO 2768-1 / -2 (General tolerances)

Keywords: ISO 8820-6:2019, single-bolt fuse-links, road vehicles fuse links, automotive fuse standard, fuse testing, rated current, breaking capacity, voltage drop, operating time.