Overview
IEC 60512-9-5:2020 - "Connectors for electrical and electronic equipment - Tests and measurements - Part 9-5: Endurance tests - Test 9e: Current loading, cyclic" defines a standardized method to thermally condition and endurance-test solderless connections and connector terminations by cyclic current loading. This second edition (2020) replaces the 2010 edition and introduces a new flexible Method B in addition to the traditional Method A, to better accommodate products with larger thermal mass.
Key topics and technical requirements
- Scope and objective
- Applies when called up by a detail product specification for connectors and solderless connections within IEC TC 48 scope; may be used for similar devices.
- Objective: verify conductor & termination material, termination method (and tools) against thermal creep and loss of performance under repeated heating/cooling cycles.
- Test methods
- Method A: traditional fixed duty cycle - time ON = 45 min, time OFF = 15 min (suitable for small connections, e.g., conductors ≤ 10 mm²).
- Method B: adjustable ON/OFF determined experimentally during the first cycle; allows increased current or forced cooling to reach upper limiting temperature (ULT) and ambient more quickly - suited for larger thermal mass.
- Cycle definition
- Time “ON” = interval to heat specimen from ambient to the specified ULT.
- Time “OFF” = interval to cool back to ambient; ON+OFF = one cycle.
- Equipment and measurements
- Requires a suitable current source (AC or DC), voltmeter, micro-ohm meter; output voltage must cover voltage drop across test circuit (daisy-chained specimens allowed if thermally independent).
- Pre-conditioning under standard atmospheric conditions for 24 h before initial measurements.
- Initial and final measurements (e.g., contact resistance, voltage drop) per relevant IEC 60512 parts.
- Specimen preparation
- Specimens made with the relevant termination and conductor as per detail product specification; mounting and series wiring rules to avoid thermal interaction.
Applications and who uses it
- Useful for:
- Connector designers and R&D teams validating termination designs.
- Test engineers and laboratories performing reliability/endurance testing.
- Manufacturers qualifying solderless terminations (crimps, press-fit, etc.) and conductor/tool combinations.
- Compliance and quality teams referencing IEC test methods in product specifications and qualification plans.
- Practical benefits: identifies thermal degradation, creep-related contact failures, and confirms correct material/tool combination before production.
Related standards
- IEC 60352 series (Solderless connections)
- IEC 60512-1 (General), and related IEC 60512 parts for contact resistance and electrical/insulation tests (e.g., 60512-2-1, 60512-2-2, 60512-3-1).
Keywords: IEC 60512-9-5, cyclic current loading, endurance tests, solderless connections, connector testing, thermal stress, contact resistance, Method A, Method B, ULT.