EN 3841-508:2004

Overview

EN 3841-508:2004 is a CEN/AECMA aerospace test method that specifies how to verify the capability of circuit breakers to withstand centrifugal acceleration. It is part of the Aerospace series for circuit breaker test methods and is intended to be used together with EN 3841-100 (General). The procedure references ISO 2669 for steady-state acceleration testing and defines mounting, test sequence and performance checks to confirm contact stability under rotation.

Key topics and technical requirements

• Scope: Method for verifying circuit breaker behaviour under centrifugal acceleration; used with EN 3841-100.
• Mounting requirements
  • Circuit breakers are mounted in a centrifuge on a rotating support per EN 3841-100 (clauses 4.2 and 4.3).
  • Electrical connections use cable sections specified in EN 3841-100, Table 1.
  • Connection cables attached approx. 100 mm from the terminals.
  • Devices and cables mounted with torque values indicated in the product standard.
  • Circuit breakers must be shielded from airflow by a screen during the test.
• Test procedure
  • Steady-state acceleration test in accordance with ISO 2669.
  • Tests are performed for six planes of the main axis of the circuit breaker (i.e., orientations around the axis).
  • Two tests per direction:
    • 1st test: 10 minutes in the open position.
    • 2nd test: 10 minutes in the closed position at 90% of rated current.
  • The specific acceleration value to apply is defined in the technical specification for the product.
• Performance criterion
  • During test, contacts must not unintentionally change state for longer than 10 µs:
    • Open-position devices must not close ≥10 µs.
    • Closed-position devices must not open ≥10 µs.
• Requirements
  • Final acceptance and pass/fail criteria follow the applicable product standard and the project technical specification.

Applications and users

• Intended for aerospace manufacturers, design and test engineers, qualification and certification laboratories, and quality assurance teams involved in:
  • Component qualification and environmental testing of circuit breakers for aircraft and aerospace systems.
  • Verification of performance where rotational/centrifugal loading is expected (e.g., rotorborne equipment, mounts on spinning platforms).
  • Supplier acceptance testing and compliance documentation for procurement and certification.

Related standards

• EN 3841-100 - Aerospace series - Circuit breakers - Test methods - Part 100: General
• ISO 2669 - Environmental tests for aircraft equipment - Steady-state acceleration

Keywords: EN 3841-508, centrifugal acceleration, circuit breakers, aerospace test methods, EN 3841-100, ISO 2669, centrifuge testing, steady-state acceleration.