ISO 24071:2022

INTERNATIONAL ISO
STANDARD 24071
First edition
2022-08
Aircraft — Auto-transformer
rectifier units (ATRUs) — General
requirements
Aéronefs — Autotransformateurs-redresseurs (ATRU) — Exigences
générales
Reference number
© ISO 2022
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Published in Switzerland
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Contents Page
Foreword .v
Introduction . vi
1 S c op e . 1
2 N ormative references . 1
3 T erms and definitions . 1
4 G eneral requirements . 1
4.1 Specification sheets . . 1
4.2 M aterials . 1
4.2.1 S election of materials . 1
4.2.2 M etal materials . 1
4.2.3 N on-metal materials . 2
4.3 D esign and construction . 2
4.3.1 General mechanical and electrical design . 2
4.3.2 E lectrical design . 2
4.3.3 Mechanical design . 3
4.4 S ize and mass . 4
4 . 5 C olou r . 4
4.6 P rocessing quality and appearance quality . 4
4.6.1 Processing quality . . 4
4.6.2 A ppearance quality . 4
4.7 M arkings . 4
4.7.1 C omponents and parts . 4
4.7.2 N ameplate of ATRUs . 4
4.8 Performance . 5
4 . 8 .1 I nput p ower . 5
4 . 8 . 2 O ut put p ower . 5
4.8.3 Efficiency . 7
4.8.4 Overload . 7
4 . 8 . 5 S hor t c i r c u it . 7
4.8.6 Soft starting . 7
4.8.7 Insulation resistance and dielectric strength . 8
4.8.8 I nfluence on the input power system. 8
4.8.9 E lectrical protection . 8
4.9 A coustical noise . 8
4.10 R eliability . 8
4.11 M aintainability . 8
4.12 Interchangeability . 9
5 E nvironmental conditions and test procedures . 9
6 Qualification inspection .10
6.1 General . 10
6.2 M ethods of inspection . 10
6.2.1 P rocessing quality and appearance quality . 10
6 . 2 . 2 C olou r . 11
6.2.3 M arkings . 11
6.2.4 S ize and mass. 11
6.2.5 I nsulation resistance and dielectric strength . 11
6.2.6 N ormal steady-state input voltage . 11
6.2.7 A bnormal steady-state input voltage . 11
6.2.8 I nput voltage spikes .12
6.2.9 I nput power interruptions .12
6.2.10 I nput frequency transients .12
6.2.11 Output voltage ripple .12
iii
6.2.12 Output voltage frequency characteristics .12
6.2.13 Output voltage distortion factor .12
6.2.14 Output voltage transients.12
6.2.15 Output power interruptions. 13
6.2.16 Efficiency . 13
6.2.17 Overload .13
6 . 2 .18 S hor t c i r c u it . 13
6.2.19 Soft starting . 13
6.2.20 Influence on the input power system. 13
6.2.21 E lectrical protection . 13
6.2.22 A coustical noise . . 13
6.2.23 Reliability . 13
6.2.24 Maintainability . 14
6.2.25 Interchangeability . 14
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Foreword
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electrotechnical standardization.
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described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
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Attention is drawn to the possibility that some of the elements of this document may be the subject
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