IEC PAS 63108:2017

IEC PAS 63108 ®
Edition 1.0 2017-05
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
Electrical installations in ships – Primary DC distribution – System design
architecture
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IEC PAS 63108 ®
Edition 1.0 2017-05
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
Electrical installations in ships – Primary DC distribution – System design

architecture
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 47.020.60 ISBN 978-2-8322-4400-5

– 2 – IEC PAS 63108:2017  IEC 2017
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 General requirements . 8
4.1 General . 8
4.2 Acceptance of substitutes or alternatives . 9
4.3 Provisions for maximum load . 9
4.4 Additions and alterations . 9
4.5 Environmental conditions . 9
4.6 Power supply system characteristics . 9
4.6.1 General . 9
4.6.2 DC distribution systems limits . 9
4.7 Mechanical protection . 9
4.8 Enclosures . 9
5 System design . 10
5.1 General . 10
5.2 Power quality . 10
5.3 Combined AC and DC distribution systems . 10
5.4 Black-out start up and start from dead ship condition . 10
5.5 DC distribution systems . 10
5.6 AC distribution systems . 10
5.7 Shore powered charging systems . 10
5.8 Short-circuit currents in combined AC and DC systems . 11
5.8.1 General . 11
5.8.2 Short-circuit current in DC systems . 11
5.9 System studies and calculations . 11
5.10 Protection . 11
5.10.1 General . 11
5.10.2 Fixed and variable speed AC generator protection . 12
5.10.3 Battery circuits . 12
5.10.4 Safety barriers for energy storage systems . 12
5.10.5 Protection against electric shock . 13
5.11 Protection of interconnection to shore . 13
6 Sources of electrical power . 13
6.1 General . 13
6.2 AC power generation with variable speed . 13
6.3 DC power generation with variable speed . 14
6.4 Various DC power sources . 14
6.5 Load sharing . 14
6.6 Transient operation . 14
7 Power distribution systems . 14
7.1 General . 14
7.2 AC distribution systems . 14
7.3 DC distribution systems . 14

7.4 DC distribution systems feeding AC distribution systems . 15
8 Equipment . 15
8.1 General . 15
8.2 Generators . 15
8.3 DC assemblies . 15
8.3.1 General . 15
8.3.2 Cooling . 15
8.3.3 Individual circuits . 16
9 Control systems . 17
9.1 General . 17
9.2 Control architecture . 17
9.3 Automatic control of vessel energy systems . 17
9.3.1 General . 17
9.3.2 Initiation of start-commands . 18
9.3.3 Transfer of start-command . 18
9.3.4 Events and indications . 18
9.3.5 Automatic reconnection to dead DC distribution system . 18
9.3.6 Automatic load sharing . 18
10 Installation . 18
11 Testing, verification and documentation . 19
11.1 General requirements . 19
11.2 Factory acceptance test . 19
11.3 On-board testing (site testing) . 19
11.4 Documentation . 19
Bibliography . 20

– 4 – IEC PAS 63108:2017  IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSTALLATIONS IN SHIPS –

Primary DC distribution – System design architecture

FOREWORD
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