SIST EN 2997-009:2015

Overview

SIST EN 2997-009:2015 is a European Standard developed by CEN that specifies the characteristics and technical requirements for protective covers designed for receptacles in aerospace circular electrical connectors. These connectors are coupled by a threaded ring and can be either fire-resistant or non fire-resistant. The standard covers operating temperature ranges from -65 °C to 175 °C continuous, 200 °C continuous, and 260 °C peak.

This standard applies specifically to the protective covers for receptacles within the EN 2997 series, ensuring compatibility with associated receptacles defined in EN 2997-003 to EN 2997-007. It is intended for use in the aerospace and defense industries, advancing reliability and safety in high-performance electrical connection systems.

Key Topics

• Protective Cover Specifications
  Defines precise dimensions, designations, material requirements, and mass limits for protective covers suitable for circular connectors coupled by threaded rings. Covers are designed to shield receptacles from environmental risks such as mechanical damage, dust, and corrosion.

• Material and Surface Treatment
  Protective covers must use materials like stainless steel or aluminum alloys with various plating options (nickel-plated, cadmium-plated, passivated stainless steel) that offer resistance to salt mist and high temperature. Chains or ropes attached for securing covers are made of stainless steel with high-temperature insulation rated to 260 °C.

• Dimensions and Design
  Detailed dimensional data based on housing size and thread class provide guidance on fitting standards. Features include attachment types such as stainless steel chains or ropes with eyelets or rings, fastening methods, and seals which are either bonded or mechanically retained.

• Marking and Designation
  Covers must be clearly marked with a unique identity block, date of manufacture, and manufacturer’s details to ensure traceability and quality compliance in aerospace manufacturing and maintenance environments.

• Classification and Attachment Types
  The standard specifies several classes of protective covers (e.g., R, W, KE, K) differentiated by material and performance traits, along with attachment options (chains, ropes, or no attachment) to suit various operational contexts.

Applications

SIST EN 2997-009:2015 protective covers are essential components in aerospace electrical systems, providing durable protection for receptacles in:

• Aircraft avionics
• Defense aerospace equipment
• Spacecraft electrical harnesses
• Harsh environment electronics where temperature extremes and fire resistance are critical
• Systems requiring precise mechanical compatibility with circular, threaded-ring coupled connectors

Using these standardized protective covers helps maintain connector integrity during handling, storage, and operation, ensuring safety and operational reliability in demanding aerospace conditions.

Related Standards

• EN 2997-001: Technical specification for circular connectors coupled by threaded ring, including fire resistance and temperature ranges.
• EN 2997-002: Performance specification and contact arrangement for these connectors.
• EN 2997-003 to EN 2997-007: Product standards for various types of receptacles compatible with the protective covers specified in EN 2997-009.
• ISO 263: Standard for inch screw threads, applicable to thread classes referenced in the EN 2997 series.

Together, these standards ensure a comprehensive approach to design, performance, and interoperability of aerospace electrical connectors and their protective accessories.

Keywords: Aerospace electrical connectors, protective cover for receptacle, circular connectors, threaded ring coupling, fire-resistant connectors, EN 2997-009, aerospace standards, high-temperature connectors, CEN standards, aerospace connector protection.