IEC 61892-1:2001

Mobile and fixed offshore units - Electrical installations - Part 1: General requirements and conditions

This part of IEC 61892 contains provisions for 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 1 500 V. This standard does not apply either to fixed equipment for medical purposes or to the electrical installations of tankers.

General Information

• Status: Published
• Publication Date: 18-Dec-2001
• 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
• Start Date: 19-Aug-2010
• Completion Date: 26-Oct-2025

Relations

• Revised: IEC 61892-1:2010 - Mobile and fixed offshore units - Electrical installations - Part 1: General requirements and conditions
• Effective Date: 05-Sep-2023

Overview

IEC 61892-1:2001 - "Mobile and fixed offshore units - Electrical installations - Part 1: General requirements and conditions" is the foundational international standard for electrical installations in the offshore petroleum industry. It defines general requirements and conditions for electrical systems on mobile and fixed units used for drilling, production, processing and storage, including pipeline pumping/pigging stations, compressor stations and exposed single buoy moorings. The standard applies to permanent, temporary, transportable or hand‑held installations for a.c. systems up to 35 000 V and d.c. systems up to 1 500 V. It does not cover tankers or fixed medical equipment.

Key Topics

• Scope and applicability: Covers all offshore units (mobile and fixed) used in petroleum operations and clarifies exclusions.
• Environmental conditions: Guidance on temperature, humidity, biological and chemically active environments that affect materials and equipment selection.
• Workmanship and materials: Requirements for durable construction and installation practices suitable for marine/offshore conditions.
• Power supply characteristics: Design considerations for a.c. and d.c. systems, frequency variations and transient behavior.
• Protection and safety:
  • Earthing/grounding (bonding and earth connections)
  • Protection against electrical shock (insulation, basic/supplementary/reinforced insulation)
  • Enclosures and IP degrees of protection (foreign objects and water ingress)
  • Precautions for vibration, mechanical shock and thermal/oil/water exposure
• Hazardous areas: Coordination with standards for electrical apparatus in explosive gas atmospheres and selection criteria for certified equipment.
• Cabling and entries: Rules for cable entries, mechanical protection and segregation.
• Maintenance and inspection: Requirements to support ongoing safety, inspection intervals and acceptance of alterations or substitutes.
• Corrosion control: Precautions against galvanic corrosion on offshore structures.

Applications

IEC 61892-1 is used to:

• Develop design specifications for offshore platforms, FPSOs, jack‑ups and fixed platforms
• Define installation and commissioning procedures for electrical systems in hazardous marine environments
• Set inspection, maintenance and alteration criteria for in-service electrical installations
• Support procurement specifications for switchgear, cabling, enclosures and electrical apparatus rated for offshore use

Who should use this standard

• Offshore electrical and systems engineers
• Platform designers and construction contractors
• Equipment manufacturers and suppliers of marine-rated electrical gear
• Classification societies, regulators and safety auditors
• Maintenance teams and asset owners operating offshore petroleum units

Related standards

• IEC 61892 series (Parts 2–7: system design, equipment, cables, mobile units, installation, hazardous areas)
• IEC 60079 (explosive atmospheres) - referenced for gas‑atmosphere equipment
• IMO SOLAS requirements - cross‑referenced for marine safety compliance

Using IEC 61892-1 helps ensure electrical safety, environmental resilience and regulatory alignment for offshore electrical installations.

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
61892-1
First edition
2001-12
Mobile and fixed offshore units –
Electrical installations –
Part 1:
General requirements and conditions
Unités fixes et mobiles en mer –
Installations électriques –
Partie 1:
Prescriptions et conditions générales

Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.

Consolidated editions
The IEC is now publishing consolidated versions of its publications. For example,

edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
Further information on IEC publications
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology. Information relating to
this publication, including its validity, is available in the IEC Catalogue of
publications (see below) in addition to new editions, amendments and corrigenda.
Information on the subjects under consideration and work in progress undertaken
by the technical committee which has prepared this publication, as well as the list
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INTERNATIONAL IEC
STANDARD
61892-1
First edition
2001-12
Mobile and fixed offshore units –
Electrical installations –
Part 1:
General requirements and conditions
Unités fixes et mobiles en mer –
Installations électriques –
Partie 1:
Prescriptions et conditions générales

 IEC 2001  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.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: [phone] e-mail: [e-mail] IEC web site http://www.iec.ch
Commission Electrotechnique Internationale
PRICE CODE
U
International Electrotechnical Commission
For price, see current catalogue

– 2 – 61892-1  IEC:2001(E)
CONTENTS
FOREWORD.3

INTRODUCTION.5

1 Scope.6

2 Normative references.6

3 Definitions .6

4 General requirements and conditions .11

4.1 General .11

4.2 Workmanship and material .11

4.3 Applicability of the standards to a.c. and d.c.12
4.4 Acceptance of substitutes or alternatives .12
4.5 Provision for maximum load.12
4.6 Additions and alterations.12
4.7 Environmental conditions .12
4.8 Materials .13
4.9 Power supply system characteristics .13
4.10 Electrical apparatus for explosive gas atmospheres .15
4.11 Precautions against galvanic corrosion .15
4.12 Clearance and creepage distances .15
4.13 Insulation.15
4.14 Maintenance and inspection.15
4.15 Cable entries .15
4.16 Precautions against vibration and mechanical shock .15
4.17 Location of electrical equipment in units.16
4.18 Spaces and compartments.16
4.19 Mechanical protection.16
4.20 Protection from heat, water, steam and oil .16
4.21 Protection against electrical shock .16
4.22 Enclosures .16
4.23 Classification tests for materials .16
Annex A (informative) Guidance on environmental conditions .17
Bibliography .26
Figure A.1 – Model shock response spectra (first-order maximum shock response spectra .25

Table 1 – Degrees of protection against foreign objects indicated by the first
characteristic numeral .10
Table 2 – Degrees of protection against water indicated by the second characteristic
numeral .10
Table 3 – Design parameters – Temperature.13
Table 4 – Design parameters – Humidity, relative .13
Table A.1 – Survey of environmental conditions related to locations.18
Table A.2 – Survey of climactic conditions .19
Table A.3 – Survey of biological conditions .22
Table A.4 – Survey of conditions dependent on chemically and mechanically active
substances .23
Table A.5 – Survey of mechanical conditions .24

61892-1  IEC:2001(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

___________
MOBILE AND FIXED OFFSHORE UNITS –

ELECTRICAL INSTALLATIONS –
Part 1: General requirements and conditions

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization
for Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61892-1 has been prepared by IEC technical committee 18:
Electrical installations of ships and of mobile and fixed offshore units.
The text of this standard based on the following documents:
FDIS Report on voting
18/916/FDIS 18/920/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.
Annex A is for information only.
IEC 61892 consists of the following parts, under the general title: Mobile and fixed offshore
units – Electrical installations:
Part 1: General requirements and conditions
Part 2: System design
Part 3: Equipment
________
Under consideration. Before IEC 61892-2 is published, reference is made to IEC 60092-201.

– 4 – 61892-1  IEC:2001(E)
Part 4: Cables
Part 5: Mobile units
Part 6: Installation
Part 7: Hazardous areas
The committee has decided that this publication remains valid until 2006. At this date, in

accordance with the committee’s decision, the publication will be

• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
________
Under consideration. Before IEC 61892-4 is published, reference is made to IEC 60092-35X-series.

61892-1  IEC:2001(E) – 5 –
INTRODUCTION
IEC 61892 forms a series of International Standards intended to enable safety in the design,

selection, installation, maintenance and use of electrical equipment for the generation, storage,

distribution and utilization of electrical energy for all purposes in offshore units which are used

for the purpose of exploration or exploitation of petroleum resources.

This part of IEC 61892 also incorporates and co-ordinates, as far as possible, existing rules

and forms a code of interpretation, where applicable, of the requirements of the International

Maritime Organization, a guide for future regulations which may be prepared and a statement

of practice for offshore unit owners, constructors and appropriate organizations.

This standard is based on equipment and practices which are in current use, but it is not
intended in any way to impede development of new or improved techniques.
The ultimate aim has been to produce a set of International Standards exclusively for the
offshore petroleum industry.
In this part of IEC 61892, references are made to other parts of the standard, which are still in
preparation. Such references are marked with footnotes. A footnote indicates which current
standard should be used until the part under preparation is published.

– 6 – 61892-1  IEC:2001(E)
MOBILE AND FIXED OFFSHORE UNITS –

ELECTRICAL INSTALLATIONS –
Part 1: General requirements and conditions

1 Scope
This part of IEC 61892 contains provisions for 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 1 500 V.
This standard does not apply either to fixed equipment for medical purposes or to the electrical
installations of tankers.
NOTE For medical rooms see IEC 60364-7-710
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 60034 (all parts), Rotating electrical machines
IEC 60079-0:1998, Electrical apparatus for explosive gas atmospheres – Part 0: General
requirements
Amendment 1 (2000)
IEC 61892-3:1999, Mobile and fixed offshore units – Electrical installations – Part 3: Equipment
IEC 61892-7:1997, Mobile and fixed offshore units – Electrical installations – Part 7: Hazardous
areas
IMO-110E, The International Convention of Safety of Life at Sea (SOLAS)
3 Definitions
For the purposes of this part of IEC 61892 the following definitions apply.
NOTE The definitions included in this part are those having general application in the IEC 61892 series.
Definitions applying to particular apparatus or equipment are included in the other parts of IEC 61892.
3.1
accessible (as applied to equipment)
condition applied to an object or device that can be inadvertently touched or approached nearer
than a safe distance by any person. It is applied to objects not suitably guarded or insulated
3.2
accessible (as applied to wiring methods)
not concealed
________
There exists a consolidated version including IEC 60079-0 (1998) and its amendment 1 (2000).

61892-1  IEC:2001(E) – 7 –
3.3
accessory
any device, other than a luminaire (see IEC 61892-3) associated with the wiring and current-

using appliances of an installation; for example, a switch, a fuse, a plug, a socket-outlet, a

lampholder, or a junction box
3.4
appropriate authority
governmental body with whose rules a unit is required to comply

3.5
bond
connection of non-current-carrying parts to ensure continuity of electrical connection, or to
equalize the potential between parts
3.6
degree of protection of enclosures
designation to indicate the degree of protection, consisting of the characteristic letters IP
followed by two numerals (the "characteristic numerals") indicating conformity with the
conditions stated in tables 1 and 2 below
NOTE The enclosures referred to in the various parts of IEC 61892 are those as defined in IEC 60529.
3.7
distribution board
assembly of one or more overcurrent protective devices for the control and distribution of
electrical power to final subcircuits
3.8
earth
general mass of the metal structure or hull of the unit
NOTE In the U.S.A. and Canada "ground" is used instead of "earth".
3.9
earthed
connected to the general mass of the structure or hull of the unit in such a manner as will
ensure at all times an immediate discharge of electrical energy without danger
3.10
essential services
services essential for the navigation, steering or manoeuvring of the mobile unit, or for the
safety of human life, or for special characteristics of the unit (for example special services)

3.11
final subcircuit
portion of a wiring system extending beyond the final overcurrent protective device of a board
3.12 Frequency
3.12.1
cyclic frequency variation
periodic deviation in frequency during normal operation such as might be caused by regularly
repeated loading
±(f - f ) × 100
max min
Cyclic frequency variation = %
2 f
nominal
– 8 – 61892-1  IEC:2001(E)
3.12.2
frequency tolerance
maximum departure from nominal frequency during normal operation conditions excluding

transient and cyclic frequency variations

NOTE Frequency tolerance is a steady state tolerance and includes variations caused by loads and governor

characteristics. It also includes variations due to environmental conditions.

3.12.3
frequency transient
sudden change in frequency which goes outside the frequency tolerance limits and returns to

and remains inside these limits within a specified recovery time after initiation of the
disturbance (time range: seconds)
3.13 Insulation
3.13.1
basic insulation
insulation applied to live parts to provide basic protection against electric shock
NOTE Basic insulation does not necessarily include insulation used exclusively for functional purposes.
3.13.2
supplementary insulation
independent insulation applied in addition to basic insulation in order to provide protection
against electric shock in the event of a failure of basic insulation
3.13.3
double insulation
insulation comprising both basic insulation and supplementary insulation
3.13.4
reinforced insulation
single insulation system applied to live parts which provides a degree of protection against
electric shock equivalent to double insulation under the conditions specified in the relevant IEC
standard
NOTE The term "insulation system" does not imply that the insulation must be one homogeneous piece. It may
comprise several layers which cannot be tested singly as supplementary or basic insulation.
3.14
live
a conductor or circuit is live when a difference of potential exists between it and earth

3.15
petroleum
complex mixture of hydrocarbons that occurs in the earth in liquid or gaseous forms
3.16
point (in wiring)
any termination of the fixed wiring intended for the attachment of a luminaire or for connecting
to the supply a current-using appliance
3.17
section board
switchgear and controlgear assembly for controlling the supply of electrical power to other
section boards, distribution boards, or final subcircuits

61892-1  IEC:2001(E) – 9 –
3.18 Spaces
3.18.1
accommodation spaces
spaces used for public spaces, corridors, lavatories, cabins, offices, crew quarters, hospitals,

game and hobby rooms, pantries containing no cooking appliances and similar spaces

3.18.2
machinery spaces
spaces containing propelling machinery, boilers, oil fuel units, steam and internal combustion
engines, hydrocarbon process equipment, water treatment and handling equipment, drilling and

associated equipment, generators and major electrical machinery, oil filling stations,

refrigerating, stabilizing, ventilation and air-conditioning machinery, and similar spaces and
trunks to such spaces
3.18.3
public spaces
portions of the accommodation used for halls, dining rooms, lounges, and similar permanently
enclosed spaces
3.18.4
service spaces
spaces used for galleys, pantries containing cooking appliances, lockers and store-rooms,
workshops other than those forming part of machinery spaces, and similar spaces and trunks
to such spaces
3.19 Voltages
3.19.1
safety voltage
voltage which does not exceed 50 V a.c. r.m.s. between conductors, or between any conductor
and earth, in a circuit isolated from the supply by means such as a safety isolating transformer,
or convertor with separate windings
voltage which does not exceed 50 V d.c. between conductors, or between any conductor and
earth, in a circuit which is isolated from higher voltage circuits
NOTE 1 Consideration should be given to the reduction of the limit of 50 V under certain conditions, such as wet
surroundings or exposure to heavy seas.
NOTE 2 The voltage limit should not be exceeded either at full load or no load, but it is assumed, for the purpose
of this definition, that any transformer or convertor is operated at its rated supply voltage.
3.19.2
voltage tolerance
maximum departure from nominal user voltage during normal operating conditions, excluding
transient and cyclic voltage variations
NOTE Voltage tolerance is a steady state tolerance and includes voltage drop in cables and voltage regulator
characteristics. It also includes variations due to environmental conditions.
3.19.3
voltage unbalance tolerance
difference between the highest and lowest phase to phase voltage
3.19.4
cyclic voltage variation
periodic voltage deviation (max. to min. r.m.s. values) of the nominal voltage, such as might be
caused by regularly repeated loading
±(U − U ) × 100
max min
Cyclic voltage variation = %
2 U
nominal
– 10 – 61892-1  IEC:2001(E)
3.19.5
voltage transient
sudden change in voltage (excluding spikes) which goes outside the nominal voltage tolerance

limits and returns to and remains inside these limits within a specified recovery time after the

initiation of the disturbance (time range: seconds)

3.20 Recovery time
3.20.1
voltage transient recovery time

time elapsed from exceeding the normal tolerance until the voltage recovers and remains

within the normal tolerance limits
3.20.2
frequency transient recovery time
time elapsed from exceeding the normal tolerance until the frequency recovers and remains
within the frequency tolerance limits
3.21 Waveform
3.21.1
total harmonic distortion
ratio of the r.m.s. value of the residue, after elimination of the fundamental, to the r.m.s. value
of the fundamental, expressed in per cent
3.21.2
single harmonic content
ratio of the effective r.m.s. value of that harmonic to the r.m.s. value of the fundamental
expressed in per cent
Table 1 – Degrees of protection against foreign objects
indicated by the first characteristic numeral
First Degree of protection
characteristic
Short description Definition
numeral
0 Non-protected –
1 Protected against solid objects A large surface of the body, such as a hand (but no protection
greater than 50 mm against deliberate access). Solid objects exceeding 50 mm in
diameter
2 Protected against solid objects Finger or similar objects not exceeding 80 mm in length
greater than 12 mm
Solid objects exceeding 12 mm in diameter
3 Protected against solid objects Tools, wires, etc. of diameter or thickness greater than

greater than 2,5 mm 2,5 mm. Solid objects exceeding 2,5 mm in diameter
4 Protected against solid objects Wires or strips of thickness greater than 1 mm. Solid objects
greater than 1 mm exceeding 1 mm in diameter
5 Dust-protected Ingress of dust is not totally prevented, but dust does not enter
in sufficient quantity to interfere with satisfactory operation of
the equipment
6 Dust-tight No ingress of dust

61892-1  IEC:2001(E) – 11 –
Table 2 – Degrees of protection against water indicated
by the second characteristic numeral

Second Degree of protection
characteristic
Short description Definition
numeral
0 Non-protected –
1 Protected against vertically falling Vertically falling drops shall have no harmful effects

water drops
2 Protected against vertically falling Vertically falling drops shall have no harmful effects when the

water drops when enclosure tilted
enclosure is tilted at any angle up to 15° on either side of

up to 15° the vertical
3 Protected against spraying water
Water sprayed at an angle up to 60° on either side of the
vertical shall have no harmful effects
4 Protected against splashing water Water splashed against the enclosure from any direction shall
have no harmful effects
5 Protected against water jets Water projected in jets against the enclosure from any
direction shall have no harmful effects
6 Protected against powerful water Water projected in powerful jets against the enclosure from
jets any direction shall have no harmful effects
7 Protected against the effects of Ingress of water in quantities causing harmful effects shall
temporary immersion in water not be possible when the enclosure is temporarily immersed
in water under standardized conditions of pressure and time
8 Protected against the effects of Ingress of water in quantities causing harmful effects shall
continuous immersion in water not be possible when the enclosure is continuously immersed
in water under conditions which shall be agreed between
manufacturer and user but which are more severe than for
numeral 7
Notes common to tables 1 and 2:
NOTE 1 For information about degrees of protection against access to hazardous parts indicated by an additional
letter and/or a supplementary letter, see IEC 60529.
NOTE 2 For information about degrees of protection for rotating electrical machines, see IEC 60034-5, Rotating
electrical machines – Part 5: Classification of degrees of protection provided by enclosures of rotating electrical
machines (IP code).
NOTE 3 Second characteristic numeral 6, will also include protection against heavy seas.
4 General requirements and conditions
4.1 General
This clause contains conditions and requirements which are common to all equipment and in-
stallations in the IEC 61892-series.
Electrical installations in units shall be such that:
– essential services will be maintained under various emergency conditions;
– the safety of crew, contractors, visitors and unit will be ensured;
– the requirements with respect to safety in this standard are considered;
– the requirements of the International Convention for the Safety of Life at Sea (SOLAS) are
met as far as applicable.
4.2 Workmanship and material
Good workmanship and adequate material are essential requirements for compliance with
these standards.
– 12 – 61892-1  IEC:2001(E)
4.3 Applicability of the standards to a.c. and d.c.

Except where a specific statement is made to the contrary, the IEC 61892 series is equally

applicable to equipment in all installations whether permanent, temporary, transportable or

hand-held, for a.c. installations up to and including 35 000 V and d.c. installations up to and

including 1 500 V.
4.4 Acceptance of substitutes or alternatives

Where in these standards any special type of equipment, construction, or arrangement is

specified, the use of any other equipment, construction or arrangement is admissible, provided

it is not less effective and reliable.

4.5 Provision for maximum load
All conductors, switchgear and accessories shall be of such size as to be capable of carrying,
without their respective ratings being exceeded, the current which can normally flow through
them. They shall be capable of carrying anticipated overloads and transient currents, for
example the starting currents of motors, without damage or reaching abnormal temperatures.
4.6 Additions and alterations
An addition or alteration, temporary or permanent, shall not be made to an existing installation
until it has been ascertained that the ratings and the condition of existing accessories,
conductors, switchgear, etc. affected, are adequate for the new situation.
Special attention is drawn to those factors affecting the existing system design such as current-
carrying capacity, short-circuit level, voltage drop, harmonics, stability and proper discri-
mination of the protective devices.
4.7 Environmental conditions
4.7.1 General
Electrical equipment shall operate satisfactorily under various environmental conditions.
Environmental conditions are characterised by a number of variables:
– one set including mainly climatic conditions, biological conditions, conditions dependent
upon chemically and mechanically active substances and mechanical conditions;
– another set dependent mainly upon locations in unit, operational patterns and transient
conditions.
For guidance only, annex A gives a list of a limited number of environmental conditions in

conjunction with some selected locations, operational patterns and transient conditions which
are considered to be generally representative.
4.7.2 Design parameters
Design parameters based on environmental conditions applicable to certain types of equipment
may be determined according to location. Where no data is available the following tables give
recommended values.
4.7.2.1 Temperature
In other parts of IEC 61892, where no "high air temperature" has been specified as a design
parameter for equipment, a value of 45 ºC shall apply.
Where equipment is designed to operate with temperatures higher or lower than those stated,
permissible temperature rises may be reduced or increased accordingly.

61892-1  IEC:2001(E) – 13 –
Table 3 – Design parameters – Temperature

º
Type of equipment Value – C
High air temperature
Cables 45
Generators and motors 50
Switchgear 45
Transformers 45
Control and instrumentation 55

Other electrical equipment 45
Low air temperature
Control and instrumentation 5 (general)
–25 (open deck)
High water temperature
Generators and motors 30
NOTE For batteries see 8.5 of IEC 61892-3.
4.7.2.2 Humidity, relative
Table 4 – Design parameters – Humidity, relative
Value
o
% C
95 up to 45
70 above 45
4.8 Materials
In general, all electrical equipment shall be constructed of durable, flame-retardant, moisture-
resistant materials, which are not subject to deterioration in the atmosphere and at the
tempe
...