SIST EN 3841-405:2005

Aerospace series - Circuit breakers - Test methods - Part 405: Fluid resistance

This standard specifies a method of verifying the circuit breakers ability to withstand fluids as defined in EN 3909.
It shall be used together with EN 3841-100.

Luft- und Raumfahrt - Schutzschalter - Prüfverfahren - Teil 405: Beständigkeit gegen Flüssigkeiten

Série aérospatiale - Disjoncteurs - Méthodes d'essais - Partie 405 : Résistance aux fluides

Aeronavtika - Odklopniki - Preskusne metode - 405. del: Odpornost proti tekočinam

General Information

• Status: Published
• Publication Date: 31-Mar-2005
• ICS: 49.060 - Aerospace electric equipment and systems
• Technical Committee: SS SPL - Technical Board for the general field
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Apr-2005
• Due Date: 01-Apr-2005
• Completion Date: 01-Apr-2005
• Ref Project: EN 3841-405:2004 - Aerospace series - Circuit breakers - Test methods - Part 405: Fluid resistance

Overview

SIST EN 3841-405:2005 is a European standard developed by CEN under the Aerospace series designed specifically for circuit breakers used in aerospace applications. This standard details the test methods for fluid resistance, ensuring that circuit breakers can withstand exposure to various fluids as defined in EN 3909 without compromising their functionality or marking integrity. It complements EN 3841-100, which covers general test methods for aerospace circuit breakers, by focusing exclusively on fluid resistance testing.

The primary goal of this standard is to validate the durability and reliability of circuit breakers in harsh aerospace environments where exposure to fluids such as hydraulic liquids, fuels, and extinguishing agents can occur. Maintaining circuit breaker performance in these conditions is critical for system safety and operational integrity in aerospace electrical systems.

Key Topics

• Scope and Purpose
  Defines the requirements to verify circuit breakers' resistance against fluid exposure ensuring functional reliability according to aerospace electrical standards.

• Test Fluids
  Utilizes fluids specified in EN 3909, which outlines standardized test fluids for aerospace electric components, including hydraulic fluids, lubricants, and fire extinguishing agents.

• Mounting and Test Setup
  Circuit breakers are tested in the closed position. Each fluid is applied with a brush to one circuit breaker to simulate fluid exposure.

• Test Conditions
  After fluid application, circuit breakers remain wet for 24 hours at ambient temperature (except for fire extinguishing agents), followed by a drying phase.

• Performance Requirements
  Manual verification of mechanical function is required both immediately after wetting and after drying. The circuit breaker must operate properly, and the current rating marking must remain legible. Minor changes in color or other markings are permitted.

• Normative References

  • EN 3841-100: Aerospace series – General test methods for circuit breakers
  • EN 3909: Aerospace series – Test fluids for electric components and sub-assemblies

Applications

This standard is essential for manufacturers, quality assurance teams, and aerospace system integrators who require certified circuit breakers capable of enduring fluid exposure without degradation. Applications include:

• Aircraft Electrical Systems
  Circuit breakers protected under this standard are suitable for use in commercial, military, and space aerospace platforms, safeguarding against fluid ingress in fuel systems, hydraulics, and fire suppression systems.

• Component Qualification
  Testing in accordance with SIST EN 3841-405:2005 is used during design verification and qualification of new circuit breaker models to meet aerospace safety requirements.

• Maintenance and Replacement
  Ensures that replacement circuit breakers provide reliable performance under continued fluid exposure, maintaining compliance with aerospace industry regulations.

Related Standards

• EN 3841-100 - Aerospace series – Circuit breakers – General test methods
  Provides the foundational testing framework, including mechanical, electrical, and environmental tests, referenced by EN 3841-405.

• EN 3909 - Aerospace series – Test fluids for electric components and sub-assemblies
  Defines the chemical and physical properties of fluids used for testing electrical aerospace components.

• AECMA-STAN Standards
  SIST EN 3841-405:2005 aligns with standards published by the European Association of Aerospace Manufacturers (AECMA), which facilitate harmonized aerospace component testing across Europe.

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Keywords: EN 3841-405, aerospace circuit breakers, fluid resistance testing, EN 3909 test fluids, electrical component durability, aerospace standards, circuit breaker qualification, aerospace electrical safety.

Standards Content (Sample)

SLOVENSKI STANDARD
01-april-2005
$HURQDYWLND2GNORSQLNL3UHVNXVQHPHWRGHGHO2GSRUQRVWSURWL
WHNRþLQDP
Aerospace series - Circuit breakers - Test methods - Part 405: Fluid resistance
Luft- und Raumfahrt - Schutzschalter - Prüfverfahren - Teil 405: Beständigkeit gegen
Flüssigkeiten
Série aérospatiale - Disjoncteurs - Méthodes d'essais - Partie 405 : Résistance aux
fluides
Ta slovenski standard je istoveten z: EN 3841-405:2004
ICS:
49.060 /HWDOVNDLQYHVROMVND Aerospace electric
HOHNWULþQDRSUHPDLQVLVWHPL equipment and systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 3841-405
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2004
ICS 49.060
English version
Aerospace series - Circuit breakers - Test methods - Part 405:
Fluid resistance
Série aérospatiale - Disjoncteurs - Méthodes d'essais - Luft- und Raumfahrt - Schutzschalter - Prüfverfahren - Teil
Partie 405 : Résistance aux fluides 405: Beständigkeit gegen Flüssigkeiten
This European Standard was approved by CEN on 10 September 2004.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2004 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 3841-405:2004: E
worldwide for CEN national Members.

Contents Page
Foreword.3
1 Scope .4
2 Normative references .4
3 Method .
...