IEC 60092-202:2016

IEC 60092-202 ®
Edition 5.0 2016-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Electrical installations in ships –
Part 202: System design – Protection

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IEC 60092-202 ®
Edition 5.0 2016-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Electrical installations in ships –

Part 202: System design – Protection

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 47.020.60 ISBN 978-2-8322-3660-4

– 2 – IEC 60092-202:2016 RLV © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
1 Scope . 8
2 Normative references. 8
3 Terms and definitions . 8
4 General requirements . 10
4.1 General . 10
4.2 Basic protection . 11
4.3 Studies and calculations . 11
5 Electrical load study . 11
6 Short-circuit current calculations . 11
7 Protection discrimination study . 12
7.1 General . 12
7.2 Current selectivity . 12
7.3 Time-current selectivity . 13
7.4 Alternative protection schemes . 13
8 Characteristics and choice of protective devices with reference to short-circuit
rating . 13
8.1 General . 13
8.2 Protective devices . 13
8.3 Rated short-circuit breaking capacity . 14
8.4 Rated short-circuit making capacity . 15
8.5 Co-ordination of short-circuit ratings with regard to continuity of service
requirements Co-ordinated choice of protective devices with regard to
discrimination requirements . 15
9 Choice of protective devices with reference to overload . 16
9.1 Mechanical switching devices . 16
9.2 Fuses for overload protection . 17
9.3 Static or solid state switching devices . 17
10 Choice of protective devices with regard to their application . 17
10.1 General . 17
10.2 Generator protection . 17
10.2.1 General . 17
10.2.2 Protection against short-circuits and fault currents on the generator side . 18
10.3 Protection of essential services . 18
10.4 Protection of transformers . 18
10.5 Circuit protection . 19
10.6 Motor protection . 19
10.7 Accumulator (storage) battery protection . 19
10.8 Protection of meters, pilot lamps and control circuits . 20
10.9 Protection of static or solid-state devices . 20
11 Reverse power and reverse current protection for AC generators . 20
12 Undervoltage protection . 21
12.1 A.C. and d.c. DC generators . 21
12.2 A.C. and d.c. DC motors . 21

13 Overvoltage protection . 21
13.1 General . 21
13.2 Transformers . 21
13.3 AC machines . 21
14 Protection against under- and over-frequency . 21
Bibliography . 22

Figure 1– Continuity of supply and service . 16

– 4 – IEC 60092-202:2016 RLV © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSTALLATIONS IN SHIPS –

Part 202: System design – Protection

FOREWORD
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International Standard IEC 60092-202 has been prepared by IEC technical
committee 18: Electrical installations of ships and of mobile and fixed offshore units.
This fifth edition cancels and replaces the fourth edition published in 1994 and
Amendment 1:1996. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
This document: Previous document:
Clause/subclause No. and heading Corresponding clause/subclause No., remark
1 Scope 1, No change
2 Normative references 2, Updated
3 Definitions 3, Several definitions changed and added
4 General requirements 4, Text changed
4.1 General New clause/subclause
4.2 Basic protection New clause/subclause
4.3 Studies and calculations New clause/subclause
5 Electrical load study New clause/subclause
6 Short-circuit current calculations 5, Heading change
- 5.1, Text changed and moved to new Clause 6
- 5.2, Text deleted, for DC-Systems reference to
IEC 61660-1 added
7 Protection discrimination study New clause/subclause
7.1 General New clause/subclause
7.2 Current selectivity New clause/s
...