EN 4644-021:2015

Overview

EN 4644-021:2015 is a European standard developed by CEN for the aerospace industry, covering electrical and optical connectors. Specifically, it defines the requirements for size 2 modular rectangular plugs without mounting holes, class A, C, and E. These plugs are designed for continuous operation at 175 °C or 125 °C and are intended for disconnect applications within modular connector systems using rectangular inserts. The corresponding receptacles are specified in related standards, ensuring complete system compatibility and high-performance connectivity in demanding aerospace environments.

Key Topics

• Connector Type: Modular, rectangular, with electrical and optical capability, using rectangular inserts.
• Plug Specification: Size 2 plug, suitable for disconnect applications, manufactured without mounting holes.
• Operating Temperature: Rated for continuous operation up to 175 °C, or 125 °C for certain applications.
• Classes Covered: Class A, C, and E - addressing a range of performance and application needs.
• System Compatibility: Designed for use within standardized connector systems, facilitating integration and replacement.
• Designation and Marking: Systematic part naming and identification, ensuring traceability and compatibility across aerospace programs.
• Physical Requirements: Standardized dimensions and weight (maximum 40 g), ensuring form-fit-function within modular connector families.

Applications

EN 4644-021 plugs are used extensively in aerospace applications, such as:

• Aircraft and spacecraft systems - Providing reliable electrical and optical connections in harsh environments.
• Avionics equipment - Ensuring stable, temperature-resistant connectivity for mission-critical systems.
• Modular wiring and harness assemblies - Facilitating easy installation and maintenance, thanks to plug-and-play design.
• Defence systems - Applied in military aircraft, UAVs, and support equipment where reliability and standardization are essential.
• Retrofit and maintenance operations - The standardization simplifies parts replacement and system upgrades.

These plugs are essential in scenarios where high-temperature capability, modularity, and reliable signal integrity are required. Their design supports robust connection without the need for mounting holes, making them suitable for compact and flexible installation within tight aerospace assemblies.

Related Standards

The EN 4644 series defines a family of modular rectangular connectors for aerospace use. Key related standards include:

• EN 4644-001: Technical specification for modular rectangular connectors, including system overview and general requirements.
• EN 4644-002: Specification for performance and contact arrangements, providing further detail on system capabilities.
• EN 4644-024: Receptacle, size 2, class A, C, and E - specifies the counterpart to this plug.
• EN 4644-025: Receptacle, size 2 with flange, for additional mechanical stability.
• EN 4644-026: Receptacle, size 2 with ground block, for grounding and shielding needs.

Organizations engaged in aerospace design, manufacturing, and maintenance should reference these interlinked standards to ensure comprehensive compliance and interoperability within modular connector systems.

By adhering to EN 4644-021:2015, aerospace professionals ensure the selection and implementation of high-performance, standardized connectors that meet rigorous industry requirements for safety, reliability, and long-term service in demanding environments.