EN 3841-505:2004

Overview

EN 3841-505:2004 is a CEN/AECMA aerospace test-method standard that defines how to verify the mechanical strength of main terminals on aerospace circuit breakers. It is part of the EN 3841 series and is intended to be used together with EN 3841-100 (general test methods) and the product technical specification. The standard establishes repeatable procedures and pass/fail criteria to confirm that terminals and their housing can withstand specified mechanical stresses without failure or unacceptable deformation.

Key Topics and Requirements

• Scope: Verifies strength of main terminals on circuit breakers used in aerospace applications.
• Reference standard: To be applied together with EN 3841-100 (general test methods) and the applicable product technical specification/product standard.
• Tightening torque test:
  • Connection screws are tightened to the torque given in the technical specification.
  • Torque is maintained for 1 minute, then screws are loosened.
  • The cycle is repeated five times for each terminal.
• Terminal body strength test:
  • Terminals are subjected to the withdrawal and pushing forces specified in the product standard.
  • Each applied force is maintained for 1 minute.
• Acceptance criteria:
  • Terminals and housing must not break or deform beyond dimensional limits set in the product standard.
  • Screw threads must not be stripped.
  • Final assessment follows requirements in the technical specification and product standard.

Practical Applications and Who Uses It

EN 3841-505 is used by organizations involved in the manufacture, qualification and maintenance of aerospace electrical components:

• Aerospace manufacturers – to qualify circuit breakers during design and production.
• Test laboratories – to perform standardized mechanical strength and durability tests.
• Quality assurance and certification teams – to demonstrate compliance with aerospace mechanical requirements.
• Suppliers and procurement – to verify supplier test data and ensure components meet contractual specifications.
• Maintenance and overhaul organizations – to validate repair or replacement terminals meet original strength requirements.

Using EN 3841-505 helps ensure reliable electrical connections under mechanical stress, reduces risk of terminal failure in service, and supports regulatory and customer compliance for aerospace electrical systems.

Related Standards

• EN 3841-100 - Aerospace series: Circuit breakers - Test methods - Part 100: General (mandatory companion document).
• Product technical specifications / product standard - defines the specific torques, forces, and dimensional limits to be applied for a given circuit breaker model.

Keywords: EN 3841-505, circuit breaker terminal strength, aerospace circuit breakers, test methods, terminal torque test, terminal withdrawal force, EN 3841-100.