SIST EN 2349-302:2009

Overview

SIST EN 2349-302:2009 is a European standard developed by CEN that defines specific requirements and test procedures for measuring the insulation resistance of aerospace relays and contactors. This standard is part of the broader EN 2349 aerospace series and must be used in conjunction with EN 2349-100, which covers general requirements for relays and contactors. The purpose of SIST EN 2349-302:2009 is to ensure electrical safety and operational reliability of essential aircraft components by standardizing insulation resistance testing methods.

Key Topics

• Scope and Application
  The standard applies specifically to relays and contactors used in aerospace electrical systems. It provides a detailed test method to verify insulation resistance, critical for preventing electrical faults and ensuring component durability in aviation environments.

• Test Methodology

  • Insulation resistance is measured between all insulated terminals and between terminals and the housing.
  • Tests are conducted with the device both energized and de-energized, simulating different operational states.
  • Testing procedures conform to ISO 2678 standards for insulation resistance and high voltage.
  • A test voltage of 500 V DC is applied during the measurement.
  • The insulation resistance must achieve the specified values within 2 minutes of testing.
  • During tests when de-energized, coil terminals must be shorted to each other to maintain consistent conditions.

• Compliance and Criteria
  Eligible relays and contactors must meet or exceed minimum insulation resistance values as stated in their respective product standards, assuring conformance with aerospace safety and quality requirements.

• Normative References
  The standard references related documents including EN 2349-100 for general requirements and ISO 2678 for environmental and electrical testing, anchoring the procedures in internationally recognized aerospace electrical standards.

Applications

SIST EN 2349-302:2009 is vital for aerospace manufacturers, quality control engineers, and certification bodies responsible for ensuring the reliability of electrical control devices such as relays and contactors. By standardizing insulation resistance testing, this standard helps:

• Enhance flight safety through dependable electrical isolation and prevention of short circuits.
• Support aerospace component certification processes aligned with European and international regulatory frameworks.
• Facilitate consistent quality assurance across multi-national aerospace supply chains.
• Reduce maintenance costs by early detection of insulation degradation in relays and contactors.

This standard is applicable during design validation, production testing, maintenance inspections, and quality audits of aerospace electrical components.

Related Standards

• EN 2349-100: Aerospace series - General requirements for relays and contactors
  Provides foundational requirements that complement the specific insulation resistance testing procedures in EN 2349-302.

• ISO 2678: Environmental tests for aircraft electrical equipment
  Specifies standardized test methods for insulation resistance and high voltage testing applicable to aerospace electrical components, forming the technical basis for EN 2349-302 procedures.

• EN 2349 series
  A comprehensive set of standards outlining requirements and test procedures for various aspects of aerospace relays and contactors, including mechanical, environmental, and electrical characteristics.

Summary

SIST EN 2349-302:2009 establishes critical testing criteria for the insulation resistance of aerospace relays and contactors, ensuring these components meet stringent safety and reliability standards. Incorporating this standard into aerospace manufacturing and maintenance practices guarantees robust electrical insulation, compliance with international aerospace regulations, and high operational dependability of aircraft electrical systems. For aerospace engineers and quality professionals, adherence to SIST EN 2349-302:2009 provides a reliable framework to validate insulation performance, supporting safe and efficient aviation operations.