Overview - ISO 6518-2:1995 (Ignition systems test methods)
ISO 6518-2:1995 specifies electrical performance and function test methods for battery‑supplied ignition systems used on road vehicles with spark‑ignited internal combustion engines. This second edition replaces the 1982 version and introduces two standardized test approaches (Method A and Method B) to obtain the parameters needed to calculate system output energy. The standard is intended for repeatable bench testing of ignition coils, distributors, switching devices and complete ignition systems.
Key topics and technical requirements
- Two test arrangements
- Method A (spark gaps) - measures inductive spark energy (Espi) using controlled spark gaps; output called spark energy.
- Method B (Zener diode string) - measures Zener discharge energy (Ezd) with Zener diode strings (1 kV for single‑ended coils; 1 kV and 0.5 kV for double‑ended coils); recommended for comparative coil and current‑interruption testing.
- Components and system configurations
- Single‑ended and double‑ended coils, ballast resistors, distributors (mechanical or distributorless), auxiliary switching devices and plug‑top coils.
- Measured parameters
- Available voltage (Uav), minimum available voltage (Uavm), secondary output voltage (Us), spark/Zener discharge duration, maximum spark/discharge current (Ispm / Izdm), secondary voltage rise time, coil primary induced voltage (Upind), ignition‑limiting load resistance (R15kV), average current input.
- Energy calculations: Espi and Ezd are calculated by integrating measured voltage × current over the spark/discharge duration.
- Test equipment and limits
- Oscilloscope: ≤35 ns rise time, ≥10 MHz bandwidth; overall measurement uncertainty