Overview
IEC 60068-2-43:2003 is an international standard developed by the International Electrotechnical Commission (IEC), titled Environmental testing – Part 2-43: Tests – Test Kd: Hydrogen sulphide test for contacts and connections. This standard provides an accelerated testing method to evaluate the effects of tarnishing on silver and silver alloys that are commonly used in electrical contacts and connections. It is widely recognized in quality assurance, component engineering, and electromechanical industries for assessing contact durability in the presence of hydrogen sulphide.
By simulating harsh environmental conditions, IEC 60068-2-43 enables reliable and comparative evaluations of the resistance of silver-based contacts against sulfur-induced tarnishing. However, this test is not intended as a general corrosion test for predicting performance in all industrial atmospheres.
Key Topics
- Purpose: The standard outlines a method to quickly assess how silver and silver alloy materials used in contacts and connections respond to atmospheres containing hydrogen sulphide.
- Scope: Relevant for manufacturers and users of electrical and electronic equipment where contact reliability is critical.
- Test Atmosphere: Specifies controlled levels of hydrogen sulphide, temperature, and humidity to create a consistent and measurable corrosive environment.
- Apparatus Requirements: Details the necessary construction and characteristics of test chambers and supportive equipment, ensuring accurate and repeatable test conditions.
- Test Procedure:
- Preparation of specimens, including preconditioning.
- Placement of uncleaned or specified specimens within the chamber.
- Continuous exposure for defined durations (typically 4, 10, or 21 days).
- Strict control over electrical and mechanical loading conditions.
- Performance Criterion: The main indicator of failure or degradation is increased contact resistance resulting from exposure.
- Measurement and Assessment: Emphasizes standardized contact resistance measurement both before and after exposure.
Applications
IEC 60068-2-43 plays a crucial role in several practical contexts, including:
- Quality Control: Assists manufacturers in ensuring that their products can withstand atmospheric pollutants, thereby improving product reliability.
- Comparative Assessment: Useful for comparing the tarnish resistance of various silver coatings or materials under controlled conditions.
- Design Validation: Provides component engineers and designers important feedback on material selection and surface treatments for contacts and connectors.
- Supplier Qualification: Helps end-users and OEMs evaluate and qualify suppliers based on their products' compliance with environmental resistance standards.
This standard is especially relevant for the electronics, telecommunications, automotive, and power distribution industries, where failure of electrical contacts due to corrosion can cause significant issues.
Related Standards
For a comprehensive approach to environmental testing and contact reliability, the following related IEC standards should also be considered:
- IEC 60068-1: Environmental testing – Part 1: General and guidance
- IEC 60068-2-46: Environmental testing – Part 2: Tests. Guidance to Test Kd: Hydrogen sulphide test for contacts and connections
- IEC 60355: Appraisal of problems of accelerated testing for atmospheric corrosion
- IEC 60512-2-1: Connectors for electronic equipment – Tests and measurements – Part 2-1: Electrical continuity and contact resistance tests
By integrating IEC 60068-2-43 with these related standards, organizations can establish robust procedures for ensuring long-term performance and reliability of contacts and connections in corrosive environments.
Keywords: IEC 60068-2-43, hydrogen sulphide test, environmental testing, silver contacts, tarnishing, corrosion resistance, electrical connectors, contact reliability, standard.