IEC 61892-2:2005

Mobile and fixed offshore units - Electrical installations - Part 2: System design

This part of IEC 61892 contains provisions for system design of electrical installations in mobile and fixed units used in the offshore petroleum industry for drilling, production, processing and for storage purposes, including pipeline, pumping or 'pigging' stations, compressor stations and exposed location single buoy moorings. It applies to all installations, whether permanent, temporary, transportable or hand-held, to a.c. installations up to and including 35 000 V and d.c. installations up to and including 750 V.(a.c. and d.c. voltages are nominal values) This standard does not apply either to fixed equipment used for medical purposes or to the electrical installations of tankers.

General Information

• Status: Published
• Publication Date: 23-Mar-2005
• ICS: 47.020.60 - Electrical equipment of ships and of marine structures
• Technical Committee: TC 18 - Electrical installations of ships and of mobile and fixed offshore units
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 15-Mar-2012

Relations

• Revised: IEC 61892-2:2012 - Mobile and fixed offshore units - Electrical installations - Part 2: System design
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 61892-2
First edition
2005-03
Mobile and fixed offshore units –
Electrical installations –
Part 2:
System design
Reference number
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INTERNATIONAL IEC
STANDARD 61892-2
First edition
2005-03
Mobile and fixed offshore units –
Electrical installations –
Part 2:
System design
 IEC 2005  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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International Electrotechnical Commission
Международная Электротехническая Комиссия
For price, see current catalogue

– 2 – 61892-2  IEC:2005(E)
CONTENTS
FOREWORD.5
INTRODUCTION.7

1 Scope .8
2 Normative references .8
3 Terms and definitions .9
4 Sources of electrical power.14
4.1 General .14
4.2 Main source of electrical power.15
4.3 Emergency source of electrical power .15
4.4 Additional requirements for periodically unattended machinery spaces.17
4.5 General requirements for renewable sources of electrical power.17
4.6 Arrangement and location .18
4.7 Output.19
4.8 Additional requirements for electrical emergency power systems .20
4.9 Starting arrangements for emergency generators .20
5 System earthing .21
5.1 General .21
5.2 General requirements .21
5.3 Neutral earthing methods.21
5.4 Neutral earthing for systems up to and including 1 000 V.21
5.5 Neutral earthing for systems above 1 000 V .22
5.6 Generators operated in parallel with source transformers .22
5.7 Earthing resistors, connection to hull/structure .23
6 Distribution systems .24
6.1 DC distribution systems .24
6.2 AC distribution systems .29
7 Distribution system requirements .33
7.1 Earthed distribution systems .33
7.2 Methods of distribution.34
7.3 Balance of loads.34
7.4 Final circuits.34
7.5 Control circuits .35
7.6 Socket-outlets .35
7.7 Shore connections for mobile units.36
7.8 Motor circuits.36
8 Diversity (demand) factors .37
8.1 Final circuits.37
8.2 Circuits other than final circuits .37
8.3 Application of diversity (demand) factors .37
8.4 Motive-power circuits - General.37
9 System study and calculations .38
9.1 General .38
9.2 Electrical load study .38
9.3 Load flow calculations.39

61892-2  IEC:2005(E) – 3 –
9.4 Short-circuit calculations.39
9.5 Protection and discrimination study .41
9.6 Power system dynamic calculations .41
9.7 Calculation of harmonic currents and voltages.43
10 Protection.43
10.1 General .43
10.2 Characteristic and choice of protective devices with reference to short-circuit
rating .44
10.3 Choice of protective devices with reference to overload.45
10.4 Choice of protective devices with regard to their application .45
10.5 Undervoltage protection.48
10.6 Overvoltage protection.49
11 Lighting .49
11.1 General .49
11.2 General lighting system .50
11.3 Emergency lighting system .51
11.4 Escape lighting system .51
11.5 Lighting circuits in machinery spaces, accommodation spaces, open deck
spaces, etc.52
11.6 Luminaires .53
11.6.1 Discharge lamp luminaires of voltages above 250 V.53
11.6.2 Searchlights.53
12 Control and instrumentation .53
12.1 Safeguarding.53
12.2 Supply arrangement .53
12.3 Dependability .53
12.4 Safety .53
12.5 Segregation.53
12.6 Performance.54
12.7 Integration.54
12.8 Development activities.54
12.9 Electromagnetic compatability.54
12.10 Design.54
12.11 Installation and ergonomics .55
12.12 Specific installations .56
12.13 Automatic control installations for electrical power supply.58
12.14 Machinery control installations .60
12.15 Public address and general alarm systems.60
12.16 Computer based systems.61
12.17 Software.63
12.18 Tests.65
12.19 Documentation .66
13 Degrees of protection by enclosures .67
13.1 General .67

Bibliography .69

– 4 – 61892-2 © IEC:2005(E)
Figure 1 – Continuity of supply/continuity of service.14
Figure 2 – TN-S d.c. system.25
Figure 3 – TN-C d.c. system.26
Figure 4 – TN-C-S d.c. system .27
Figure 5 – IT d.c. system .28
Figure 6 – TN-S a.c. system.30
Figure 7 – TN-C-S a.c. system .30
Figure 8 – TN-C a.c. system.31
Figure 9 – IT a.c. system .31

Table 1
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