SIST EN 2349-303:2009

Overview

SIST EN 2349-303:2009 is a European standard developed by the AeroSpace and Defense Industries Association of Europe (ASD-STAN) and adopted by CEN. It specifies the method for testing the dielectric strength of relays and contactors used in aerospace applications. This standard ensures that key aerospace electromechanical components meet stringent electrical insulation criteria to maintain safety, reliability, and performance under high voltage stress.

The standard is intended to be used in conjunction with EN 2349-100, which outlines the general requirements and test procedures for relays and contactors in aerospace systems. Compliance with SIST EN 2349-303:2009 helps manufacturers and aerospace manufacturers verify that products can withstand high voltage conditions without damage or excessive leakage current.

Key Topics

• Scope and Purpose
  SIST EN 2349-303:2009 focuses exclusively on dielectric strength testing, a critical factor in ensuring electrical insulation integrity in aerospace relays and contactors.

• Test Procedures

  • Application of test voltage between all insulated terminals and between terminals and housing
  • Testing both in de-energized and energized states
  • Following ISO 2678 methodologies for high voltage and insulation resistance testing
  • Specific test durations: 2–5 seconds for batch and acceptance testing, 1 minute for certification testing
  • Coil terminals shorted during de-energized testing to simulate operational conditions

• Test Criteria

  • Equipment must not sustain damage during testing
  • Leakage current limited to a maximum of 1 mA during tests
  • Compliance with voltage values as defined in related product standards

• Normative References

  • EN 2349-100 for general requirements on aerospace relays and contactors
  • ISO 2678 for environmental and electrical insulation testing

Applications

SIST EN 2349-303:2009 is primarily utilized in the aerospace industry where relays and contactors are critical components for electrical system control, power distribution, and safety functions. Its practical applications include:

• Design and manufacturing of aerospace relays and contactors ensuring they meet rigorous dielectric strength requirements.
• Quality assurance and batch testing during production to validate insulation and withstand voltage performance.
• Certification processes for aerospace components to comply with both European and international aerospace electrical standards.
• Maintenance and inspection in aerospace electrical systems, ensuring relays and contactors retain insulation integrity over the lifespan of aircraft.

This standard supports manufacturers, aerospace engineers, and certification bodies focused on reliability and safety in flight-critical electrical systems.

Related Standards

• EN 2349-100: Aerospace series - General requirements and test procedures for relays and contactors
  Provides foundational test and design guidelines that SIST EN 2349-303:2009 builds upon specifically for dielectric strength evaluation.

• ISO 2678: Environmental tests for aircraft electrical equipment - Insulation resistance and high voltage tests
  Defines the environmental and electrical conditions under which dielectric strength tests are to be conducted.

• Other parts of the EN 2349 series cover various test procedures and requirements ensuring comprehensive evaluation for aerospace relay and contactor performance.

Adopting SIST EN 2349-303:2009 helps aerospace component manufacturers demonstrate compliance with recognized European aviation standards, optimize product safety, and improve electrical system reliability by validating the dielectric strength of relays and contactors under operational conditions. This contributes to safer, more reliable aerospace electrical systems overall.