EN 2349-412:2007

Overview

EN 2349-412:2007 is a European aerospace standard developed by the AeroSpace and Defense Industries Association of Europe (ASD-STAN) and approved by CEN. It defines requirements and test procedures for verifying the sealing integrity of relays and contactors used in aerospace applications. This standard focuses specifically on seal leakage rate testing and must be applied alongside EN 2349-100, which covers general requirements for aerospace relays and contactors.

By ensuring hermetic sealing performance, EN 2349-412:2007 protects sensitive aerospace electrical components from environmental contaminants such as moisture and gases, which can degrade reliability and safety in critical aerospace systems.

Key Topics

• Scope
  Specifies methods to check leakage rates of aerospace-grade relays and contactors, vital for airworthiness in aerospace electric equipment.

• Normative References
  Relies on standards such as EN 2349-100 (General relay requirements), EN 2349-201 (Visual inspection), and IEC 60068-2-17 (Test Q for sealing).

• Test Method

  • Testing is conducted on the switching devices separately if the relay/contactor has plug-socket holders.
  • Seal testing follows the environmental test conditions described in IEC 60068-2-17, ensuring consistent measurement of leakage rates.

• Leakage Requirements

  • For devices with a sealed volume larger than 30 cm³, the maximum allowable leakage rate is 1 × 10⁻⁶ cm³/s per 15 cm³ volume under a 1 bar pressure differential.
  • For smaller volumes (<30 cm³), the leakage must not exceed 1 × 10⁻⁸ cm³/s.
  • Liquid-tightness requirements demand no visible bubbles 10 seconds after immersion testing, verifying liquid ingress protection.

• Inspection
  Visual inspections in line with EN 2349-201 must confirm no evidence of leakage or bubbles after testing.

Applications

• Aerospace Electrical Systems
  Ensures the reliability of relays and contactors by confirming their hermetic sealing against gases and liquids in demanding aerospace environments where pressure, vibration, and temperature vary widely.

• Quality Assurance in Aerospace Manufacturing
  Aerospace component manufacturers use this standard to verify product compliance with strict leakage tolerances, reducing failure risks in flight systems.

• Aerospace Maintenance and Testing
  Enables aerospace maintenance crews to check relay seals during periodic inspections to prevent contamination-related failures and uphold safety standards.

• Research and Development
  Used to guide design improvements in sealing technologies for relay and contactor assemblies to meet evolving aerospace reliability requirements.

Related Standards

• EN 2349-100 – Aerospace relays and contactors general requirements and test procedures.
• EN 2349-201 – Visual inspection methods for aerospace relays and contactors.
• IEC 60068-2-17 – Basic environmental testing procedures: Test Q for sealing, used as the test method to assess both gas and liquid tightness in this standard.

Summary

EN 2349-412:2007 is a critical aerospace industry standard detailing test procedures and leakage rate requirements for relay and contactor seals. It ensures hermetic integrity essential for the reliable operation of aerospace electric components under extreme conditions. Complying with this standard supports aerospace manufacturers and operators in maintaining component durability and safety, which are paramount in aviation systems.

Keywords: aerospace standard, EN 2349-412, relay seal testing, contactor leakage test, aerospace electrical equipment, hermetic sealing, aerospace relays, leakage rate requirements, IEC 60068-2-17, aerospace component testing