IEC 60214-2:2004

INTERNATIONAL IEC
STANDARD 60214-2
First edition
2004-10
Tap-changers –
Part 2:
Application guide
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INTERNATIONAL IEC
STANDARD 60214-2
First edition
2004-10
Tap-changers –
Part 2:
Application guide
 IEC 2004  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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– 2 – 60214-2  IEC:2004(E)
CONTENTS
FOREWORD.4

INTRODUCTION.6

1 Scope.7

2 Normative references .7

3 Terms and definitions .7

4 Symbols and abbreviations.7

5 Types of tap-changer.8
5.1 General .8
5.2 On-load tap-changers.8
5.3 Off-circuit tap-changers .15
5.4 Liquid-immersed tap-changers .15
5.5 Dry-type tap-changers .16
5.6 Other types .17
5.7 Protective devices .18
6 Selection of tap-changers .21
6.1 General .21
6.2 On-load tap-changers.22
6.3 Off-circuit tap-changers .27
7 Location of liquid-immersed tap-changers.29
7.1 Tap selectors .29
7.2 Diverter and selector switches.29
8 Fittings .29
8.1 Valves, air-release vents and liquid sampling devices .29
8.2 Liquid level gauges .29
8.3 Low liquid level alarms .30
8.4 Nameplate and other plates.30
8.5 Devices to aid maintenance.30
8.6 Dehydrating breathers .30
9 Field service (operation, maintenance and monitoring) .30
9.1 Operation .30

9.2 Maintenance.32
9.3 Monitoring in service .32
10 Information to be provided by the transformer manufacturer .34
10.1 Information required at the enquiry or order stage for an on-load tap-changer .34
10.2 Information required with enquiry or order for off-circuit tap-changers .36
10.3 Documentation .36
11 Protection and safety.37
11.1 Protection.37
11.2 Safety aspects.37
11.3 Immersing medium .37

60214-2  IEC:2004(E) – 3 –
Figure 1 – External separate selector and diverter compartments (for mounting on the

end or side of the transformer).9

Figure 2 – External mounted selector switch tap-changer (for mounting on the end or

side of the transformer).10

Figure 3 – External mounted in-tank with separate barrier board.10

Figure 4 – In-tank separate selector and diverter switch .12

Figure 5 – In-tank selector switch tap-changer .13

– 4 – 60214-2  IEC:2004(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
TAP-CHANGERS –
Part 2: Application guide
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60214-2 has been prepared by IEC technical committee 14: Power
transformers.
This standard cancels and replaces IEC 60542 (1976) and its amendment 1 (1988). This first
edition constitutes a technical revision of that standard.
The text of this standard is based on the following documents:
FDIS Report on voting
14/490/FDIS 14/492/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 2.

60214-2  IEC:2004(E) – 5 –
IEC 60214 consists of the following parts, under the general title Tap-changers:

Part 1: Performance requirements and test methods

Part 2: Application guide
The committee has decided that the contents of this publication will remain unchanged until

the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in

the data related to the specific publication. At this date, the publication will be

• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – 60214-2  IEC:2004(E)
INTRODUCTION
The recommendations in this application guide represent advice to the tap-changer

manufacturer and purchaser.
It is stressed that the responsibility for the correct application of the fully assembled tap-

changers in connection with the transformer lies with the manufacturer of the transformer.

60214-2  IEC:2004(E) – 7 –
TAP-CHANGERS –
Part 2: Application guide
1 Scope
This part of IEC 60214 is intended to assist in the selection of tap-changers designed in

accordance with IEC 60214-1 for use in conjunction with the tapped windings of transformers
or reactors. It is also intended to assist in understanding the various types of tap-changers
and their associated equipment available. The application guide covers on-load tap-changers
(resistor and reactor types) and off-circuit tap-changers.
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 60076-1:1993, Power transformers – Part 1: General
Amendment 1(1999)
IEC 60076-3:2000, Power transformers – Part 3: Insulation levels, dielectric tests and external
clearances in air
IEC 60
...