SIST EN 4644-021:2016

Overview

SIST EN 4644-021:2016 is a European standard published by the Committee for European Normalization (CEN) that specifies the requirements for a size 2 plug used in modular rectangular electrical and optical connectors. These connectors feature rectangular inserts and are designed for continuous operation at elevated temperatures of 175 °C (or 125 °C). This part of the aerospace series focuses specifically on plugs without mounting holes, and covers classes A, C, and E.

The standard is part of a broader family of aerospace connector standards and defines key characteristics to ensure reliable disconnect applications for electrical and optical systems in aerospace environments. It complements related standards EN 4644-024, EN 4644-025, and EN 4644-026, which specify the matching receptacles.

Key Topics

• Connector Type: Modular rectangular plugs with rectangular inserts designed for high-temperature continuous operation.
• Size 2 Plug: Focuses specifically on size 2 connectors without mounting holes.
• Operating Temperature: Rated for continuous use at 175 °C or alternatively 125 °C, suitable for demanding aerospace conditions.
• Classes Covered: Applies to shell classes A, C, and E as defined in the aerospace connector family.
• Designation System: Standardized coding system to specify shell class and housing type, e.g., EN 4644-021ABX.
• Dimensional and Mass Requirements: Includes strict dimensional guidelines-critical for interoperability and space-constrained environments-and a mass limit of 40 grams to optimize weight.
• Normative References: Linked with other EN 4644 series documents that establish technical specifications, performance details, and corresponding receptacle standards.

Applications

EN 4644-021 plugs serve as integral components in aerospace electrical and optical systems where secure, modular, and high-temperature resistant connections are vital. Typical applications include:

• Aircraft avionics and control systems requiring reliable electrical disconnects.
• Optical data transmission lines in aerospace platforms that operate under extreme temperature conditions.
• Modular connector assemblies within aerospace and defense equipment to facilitate maintenance and system upgrades.
• Environments where lightweight and compact connectors improve system efficiency without sacrificing performance.
• Systems demanding standardized interface compatibility and interchangeability using the EN 4644 connector series.

By adhering to EN 4644-021 standards, manufacturers ensure that their connector products meet stringent safety, quality, and performance criteria essential for aerospace operations.

Related Standards

To provide a comprehensive connectivity solution, EN 4644-021 is used in conjunction with several related standards within the aerospace series:

• EN 4644-001: Technical specifications common to all modular rectangular connectors in the family, defining fundamental dimensions and terms.
• EN 4644-002: Overall performance requirements and contact arrangements for the range of connectors.
• EN 4644-024: Defines size 2 receptacles without flange, compatible with plugs specified in EN 4644-021.
• EN 4644-025: Describes size 2 receptacles with flange.
• EN 4644-026: Covers size 2 receptacles with ground block for classes B and F.

These complementary standards ensure full interoperability between plug and receptacle components and help maintain industry-wide consistency in aerospace electrical and optical connector design.

Keywords:

EN 4644-021, aerospace connector standard, modular rectangular plug, electrical connectors, optical connectors, high-temperature connectors, size 2 plug, aerospace electrical systems, connector standard CEN, plug without mounting holes, EN 4644 series, electrical and optical connectors, aerospace connector certification.