oSIST prEN 3475-605:2024

SLOVENSKI STANDARD
01-december-2024
Aeronavtika - Električni kabli za uporabo v zračnih plovilih - Preskusne metode -
605. del: Mokri preskus kratkega stika
Aerospace series - Cables, electrical, aircraft use - Test methods - Part 605: Wet short-
circuit test
Luft- und Raumfahrt - Elektrische Leitungen für Luftfahrtverwendung - Prüfverfahren -
Teil 605: Verhalten nach Kurzschluß, feucht
Série aérospatiale - Câbles électriques à usage aéronautique - Méthodes d’essais -
Partie 605 : Essai de court-circuit humide
Ta slovenski standard je istoveten z: prEN 3475-605
ICS:
29.060.20 Kabli Cables
49.060 Letalska in vesoljska Aerospace electric
električna oprema in sistemi equipment and systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2024
ICS 49.060 Will supersede EN 3475-605:2018
English Version
Aerospace series - Cables, electrical, aircraft use - Test
methods - Part 605: Wet short-circuit test
Série aérospatiale - Câbles électriques à usage Luft- und Raumfahrt - Elektrische Leitungen für
aéronautique - Méthodes d'essais - Partie 605 : Essai Luftfahrtverwendung - Prüfverfahren - Teil 605:
de court-circuit humide Verhalten nach Kurzschluß, feucht
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ASD-
STAN.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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 CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 3475-605:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Specimen requirements . 4
5 Preparation of specimen . 5
6 Apparatus . 6
6.1 Electrical equipment. 6
6.2 Test equipment . 7
6.3 Test protocol . 8
6.4 Test rig set-up . 8
7 Method . 9
7.1 Test procedure . 9
7.2 Examination . 9
7.3 Test report . 9
8 Requirements . 10
Bibliography . 13

European foreword
This document (prEN 3475-605:2024) has been prepared by ASD-STAN.
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 3475-605:2018.
The main changes with respect to the previous edition are as follows:
— EN 3475-605 (P3), 01/2018:
o scope: addition of a specification regarding 230 VAC test condition;
o revision of test method to update the electrical schematic circuit and add the tripping curve.
1 Scope
This document specifies a method for appraising the behaviour of cable insulation subjected to an
electric arc initiated and maintained by a contaminating fluid.
This document is intended to be used together with EN 3475-100.
The primary aim of this test is:
— to produce, in a controlled fashion, continuous failure effects, which are representative of those,
which can occur in service when a typical cable bundle is damaged and subjected to aqueous fluid
contamination such that electrical arcing occurs between cables; and
— to examine the aptitude of the insulation to track, to propagate electric arc to the electrical origin.
Originally defined for 115 VAC network, this test also proposes conditions for 230 VAC network.
However, for 230 VAC test condition only, the test EN 3475-605 can overrule and be applied as test
governance as it has been demonstrated that test EN 3475-605 is more stringent, repeatable and
reproductible compared to EN 3475-604 and EN 3475-603.
Six levels of prospective fault current have been specified for concerned cable sizes (see Clause 8). It is
agreed that larger sizes need not be assessed since the short-circuit phenomenon becomes dominant at
low line impedances.
Unless otherwise specified in the technical/product standard, sizes 002, 006 and 020 cable are
assessed.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 2350, Aerospace series — Circuit breakers — Technical specification
A-A-52083, Tape, lacing and tying, glass
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
4 Specimen requirements
Cables to be tested shall be of traceable origin and shall have passed the high voltage dielectric test
specified in the product standard.

Published by Department of Defense (DoD), available at: https://assist.dla.mil/online/start/.
5 Preparation of specimen
5.1 Cut seven (7) separate lengths approximately 0,5 m consecutively from one (1) length of cable,
and strip each of the ends of insulation to permit electrical connection. Clean each length of cable with a
clean cloth moistened with propan-2-ol (isopropyl alcohol) fluid.
5.2 Lay up the seven (7) cables as follows:
a) form the cables in a six (6) around one (1) configuration as shown in Figure 1;
b) ensure that all cables are straight and geometrically parallel, and restrained by lacing tapes such
that they are in continuous contact at least within the test zone;
c) position the lacing tapes at 50 mm spacing toward the end of the specimen as shown in Figure 2.
The first lacing tapes shall be at no more than 5 mm behind the dripping point. The tie material
shall be PTFE glass lacing tape in accordance with A-A-52083 type IV, finish D, size 3;
d) number the cables as shown in Figure 1 such that the cables in contact with the blade are numbers
A1 and B1, and the centre is N. Cables C1, A2, B2 and C2 are grouped around N.

Key
1 Drop needle
A1-A2 Phase A
B1-B2 Phase B
C1-C2 Phase C
N1-N2 Neutral cable connected to earth
Figure 1 — Specimen configuration
Key
1 Lancing tape
2 Drop needle
3 Drops
4 10 mm to 20 mm
5 Ends of the 7 cables in the same plane
Figure 2 — Test configuration
6 Apparatus
6.1 Electrical equipment
Connect the seven (7) cables of the test specimen within the circuit shown in Figure 3. This circuit shall
have the following requirements:
a) the provision of adjustable levels of prospective fault currents for the six (6) A, B and C cables;
b) a three phase 115/200 V 400 Hz (115 VAC network) or 230/400 V 400 Hz (230 VAC network)
star (Y) connected supply shall be derived from a dedicated rotary machine capable of sustaining
the maximum prospective fault current given in Table 1 (115 VAC network) or Table 2 (230 VAC
network) for at least sufficient time for circuit protection to operate. In any case, the generator shall
have a sufficient rating to provide these prospective fault currents.
c) 115 VAC or 230 VAC circuit breakers (D2) shall be single tri-pole units rated at the values specified
in Table 3.
They shall have trip characteristics in accordance with EN 2350 or as required in the product
specification.
Reference of circuit breakers used shall be recorded;
NOTE In particular cases, other ratings of thermal breaker protection could be employed in accordance with
aircraft manufacturer rules.
d) the electrical power source shall be appropriately protected, and it shall be established that no
combination of test circuit events would activate this protection;
e) the ballast Rb resistors shall be non-inductive and of appropriate power rating. Care shall be taken
to position all laboratory wiring such that inductive effects are reduced to a practical minimum.
Supply cables shall be as short as possible.
The ballast resistor Rb is in order to prevent over voltage (115 Ω – 115 W per phase for 115 VAC
network or 230 Ω – 230 W per phase for 230 VAC network) during the arc extinction phases
(opening of an inductive circuit);
f) a rheostat, Rf, limiting maximum short-circuit current per phase by simulating a line length;
g) appropriate instrumentation, recording and switching control shall be installed in accordance with
good laboratory practice;
Key
1 Supply protection
2 Test bundle
Figure 3 — Test schematic circuit
The electrical test setup method configuration has been modified as per Figure 1 for ensuring identical
current value over each phase (by an introduction of resistance on each conductor line A1, A2, B1, B2…)
as previous electrical schematic circuit definition was implying only half of current default over each
conductor due to 1 resistance for 2 phases (i.e. when 6x In was injected, only 3x In was flowing into
each conductor phase).
NOTE Further detail, explanation and justification evolutions are provided in TR 4901.
6.2 Test equipment
Construct an apparatus as shown diagrammatically in Figure 2, which include the following
minimum provisions:
a) electrical terminations to provide a ready means of connecting test specimens into the circuit as
shown in Figure 3;
b) a transparent enclosure to protect personnel from ejected molten metal and short wavelength
ultraviolet light;
c) an electrolyte delivery system which provides a constant rate of (100 ± 10) mg/min and dispenses
drops from an 18 gauge needle, cut of square at the outlet.
The needle wall thickness shall be selected such that the specified flow rate shall be delivered at
approximately six (6) drops per minute.
6.3 Test protocol
6.3.1 The procedure embraces copper cable sizes 001 to 051 (26 to 10) or copper clad aluminium
cable sizes 002 to 090 (24 to 8) and for each size six (6) values of prospective fault current have been
defined. Performance of a ca
...