prEN 2591-218

Overview

prEN 2591-218:2026 specifies a standardized method for assessing the ageing of terminal lugs and in-line splices in aerospace electrical and optical connection systems through temperature and current cycling. Developed by CEN as part of the comprehensive EN 2591 series, this standard focuses on establishing consistent test protocols to ensure the reliability of electrical connections subjected to cyclic operating conditions. prEN 2591-218 is essential for manufacturers, integrators, and testing laboratories within the aerospace sector aiming to evaluate the long-term durability of cable terminations and splices under realistic thermal and electrical load conditions.

Key Topics

• Temperature and Current Cycling: Defines the test method for repeatedly exposing terminal lugs and in-line splices to elevated temperatures and electrical currents, replicating real-world operational stresses found in aerospace environments.

  • Separate procedures for copper and aluminium cable connections.
  • Detailed cycling protocols, including number of cycles and temperature maintenance intervals.

• Specimen Preparation: Outlines requirements for assembling and wiring test specimens according to the relevant technical specification, detailing:

  • Cable type and quantity
  • Installation specifics
  • Accessory components and measurement requirements

• Severity of Test: Specifies the cycle count based on the type of cable and operating temperature:

  • For copper cables: 750 or 1,500 cycles, depending on whether the operating temperature is ≤135°C or >135°C.
  • For aluminium cables: 1,500 cycles.

• Measurement Criteria: Establishes guidelines for assessing voltage drops throughout and after the test cycles, referencing EN 2591-217 for measurement procedures. Ensures that residual performance remains within defined limits.

• Safety Considerations: Highlights the importance of operator safety due to exposure to high intensities and voltages during testing.

Applications

prEN 2591-218 is widely applicable across the aerospace industry, where the reliability of electrical and optical connections is critical for system safety and performance. Typical use cases include:

• Qualification Testing: Aerospace component manufacturers use this standard to qualify terminal lugs and in-line splices for new aircraft, satellites, and space launch vehicles.
• Quality Assurance: Integrators and suppliers verify component resilience, ensuring that connections maintain electrical performance after prolonged thermal and electrical cycling.
• Maintenance and Inspection: Aerospace maintenance organizations apply the standard for periodic inspection protocols, helping to predict ageing effects and prevent failures.
• Product Development: Design engineers implement this method during R&D to screen materials and designs for resistance to fatigue caused by cyclical stress.

Implementing prEN 2591-218 reduces the risk of in-service electrical failures by ensuring that critical connection elements withstand the challenges posed by fluctuating temperatures and electrical loads inherent to aerospace operations.

Related Standards

• EN 2591-100: Aerospace series - Elements of electrical and optical connection - Test methods - Part 100: General. This overarching document provides the general test methodology framework for the EN 2591 series and is used in conjunction with prEN 2591-218.
• prEN 2591-217: Aerospace series - Elements of electrical and optical connection - Test methods - Part 217: Voltage drop under specified current for terminal lugs and in-line splices. Directly referenced for measurement requirements during and after ageing cycles.
• EN 2591 Series: Comprehensive standards set covering various test methods for aerospace electrical and optical connections.

Adhering to prEN 2591-218 promotes consistent testing and enhanced reliability in aerospace electrical systems, supporting safety, durability, and compliance with industry regulations.