IEC 60282-1:2009

IEC 60282-1 ®
Edition 7.0 2009-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage fuses –
Part 1: Current-limiting fuses

Fusibles à haute tension –
Partie 1: Fusibles limiteurs de courant

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IEC 60282-1 ®
Edition 7.0 2009-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage fuses –
Part 1: Current-limiting fuses

Fusibles à haute tension –
Partie 1: Fusibles limiteurs de courant

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XC
CODE PRIX
ICS 29.120.50 ISBN 978-2-88910-090-3
– 2 – 60282-1 © IEC:2009
CONTENTS
FOREWORD.6

1 General .8

1.1 Scope.8

1.2 Normative references .8

2 Normal and special service conditions.8

2.1 Normal service conditions.8

2.2 Other service conditions .10

2.3 Special service conditions.10
2.4 Environmental behaviour .10
3 Terms and definitions .10
3.1 Electrical characteristics .10
3.2 Fuses and their component parts .14
3.3 Additional terms.15
4 Ratings and characteristics .17
4.1 General .17
4.2 Rated voltage .17
4.3 Rated insulation level (of a fuse-base) .18
4.4 Rated frequency .19
4.5 Rated current of the fuse-base.19
4.6 Rated current of the fuse-link.19
4.7 Temperature-rise limits.20
4.8 Rated breaking capacity.22
4.8.1 Rated maximum breaking current.22
4.8.2 Rated minimum breaking current and class .22
4.9 Limits of switching voltage .22
4.10 Rated transient recovery voltage (rated TRV).24
4.10.1 General .24
4.10.2 Representation of TRV.25
4.10.3 Representation of rated TRV.25
4.11 Time-current characteristics.26
4.12 Cut-off characteristic .27
4.13 I t characteristics .27
4.14 Mechanical characteristics of strikers.27

4.15 Special requirement for Back-Up fuses intended for use in switch-fuse
combination according to IEC 62271-105 .28
4.15.1 General .28
4.15.2 Maximum body temperature under pre-arcing conditions .29
4.15.3 Maximum arcing withstand time .29
5 Design, construction and performance .29
5.1 General requirements with respect to fuse operation .29
5.1.1 General .29
5.1.2 Standard conditions of use.29
5.1.3 Standard conditions of behaviour .30
5.2 Identifying markings.30
5.3 Dimensions .31
6 Type tests.31

60282-1 © IEC:2009 – 3 –
6.1 Conditions for making the tests.31

6.2 List of type tests .31

6.3 Common test practices for all type tests.31

6.3.1 General .31

6.3.2 Condition of device to be tested .32

6.3.3 Mounting of fuses .32

6.4 Dielectric tests.32

6.4.1 Test practices .32

6.4.2 Application of test voltage for impulse and power-frequency test .32

6.4.3 Atmospheric conditions during test.33

6.4.4 Lightning impulse voltage dry tests.33
6.4.5 Power-frequency voltage dry tests.33
6.4.6 Power-frequency wet tests .33
6.5 Temperature-rise tests and power-dissipation measurement .34
6.5.1 Test practices .34
6.5.2 Measurement of temperature .35
6.5.3 Measurement of power dissipation .36
6.6 Breaking tests .36
6.6.1 Test practices .36
6.6.2 Test procedure .43
6.6.3 Alternative test methods for Test Duty 3.47
6.6.4 Breaking tests for fuse-links of a homogeneous series .48
6.6.5 Acceptance of a homogeneous series of fuse-links by interpolation .49
6.6.6 Acceptance of a homogeneous series of fuse-links of different lengths.50
6.7 Tests for time-current characteristics .50
6.7.1 Test practices .50
6.7.2 Test procedures.50
6.8 Tests of strikers.51
6.8.1 General .51
6.8.2 Strikers to be tested.51
6.8.3 Operation tests .51
6.8.4 Test performance .52
6.9 Electromagnetic compatibility (EMC) .53
7 Special tests.53
7.1 General .53

7.2 List of special tests .53
7.3 Thermal shock tests .53
7.3.1 Test sample.53
7.3.2 Arrangement of the equipment .54
7.3.3 Test method .54
7.4 Power-dissipation tests for fuses not intended for use in enclosures.54
7.5 Waterproof test (ingress of moisture) .54
7.5.1 Test conditions .54
7.5.2 Test sample.54
7.5.3 Test method .54
7.6 Tests for Back-Up fuses for use in switch-fuse combination of IEC 62271-105 .54
7.6.1 General .54
7.6.2 Pre-arcing temperature rise test.54
7.6.3 Arcing duration withstand test .55

– 4 – 60282-1 © IEC:2009
7.7 Oil-tightness tests.55

8 Routine tests .56

9 Application guide .56

9.1 Object .56

9.2 General .56

9.3 Application.56

9.3.1 Mounting.56

9.3.2 Selection of the rated current of the fuse-link .57

9.3.3 Selection according to class (see 3.3.2) and minimum breaking
current.
9.3.4 Selection of the rated voltage of the fuse-link .59
9.3.5 Selection of the rated insulation level .59
9.3.6 Time-current characteristics of high-voltage fuses.60
9.3.7 Fuses connected in parallel.60
9.4 Operation .61
9.4.1 Locking of the fuse-link in the service position.61
9.4.2 Replacement of the fuse-link.61
9.5 Disposal .61
Annex A (normative) Method of drawing the envelope of the prospective transient
recovery voltage of a circuit and determining the representative parameters .
Annex B (informative) Reasons which led to the choice of TRV values for Test Duties
1, 2 and 3 .64
Annex C (informative) Preferred arrangements for temperature-rise tests of oil-tight
fuse-links for switchgear.66
Annex D (informative) Types and dimensions of current-limiting fuse-links specified in
existing national standards .67
Annex E (normative) Requirements for certain types of fuse-links intended for use at
surrounding temperatures above 40 °C.70
Annex F (informative) Determination of derating when the ambient temperature of the
fuse exceeds 40 °C .74
Annex G (informative) Criteria for determining I testing validity.82
t
Bibliography .83

Figure 1 – Terminology .14
Figure 2 – Permissible switching voltages for fuse-links of small current ratings

(Table 8) .23
Figure 3 – Representation of a specified TRV by a two-parameters reference line and a
delay line .26
Figure 4 – Various stages of the striker travel.28
Figure 5 – Example of a two-parameters reference line for a TRV complying with the
conditions of the type test.39
Figure 6 – Breaking tests – Arrangement of the equipment .43
Figure 7 – Breaking tests – Typical circuit diagram for Test Duties 1 and 2 .44
Figure 8 – Breaking tests – Typical circuit diagram for Test Duty 3 .44
Figure 9 – Breaking tests – Interpretation of oscillograms for Test Duty 1 .45
Figure 10 – Breaking tests – Interpretation of oscillograms for Test Duty 2 (calibration
traces as in a) of Figure 9) .46
Figure 11 – Breaking tests – Interpretation of oscillograms for Test Duty 3 .46

60282-1 © IEC:2009 – 5 –
Figure A.1 – Example of a two-parameters reference line for a TRV whose initial portion

is concave towards the left .63

Figure A.2 – Example of a two-parameters reference line for an exponential TRV .63

Figure C.1 – Test tank for temperature-rise tests of oil-tight fuses .66

Figure C.2 – Details of clamping arrangement for fuse-link in the tank .66

Figure F.1 – Derating curves for some allowed temperature limits.78

Figure F.2 – Practical example: dimensions.79

Figure F.3 – Extract from IEC 60890 .80

Figure F.4 – Practical example of application.81

Table 1 – Altitude correction factors – Test voltage and rated voltage .9
Table 2 – Altitude correction factors – Rated current and temperature rise.9
Table 3 – Rated voltages.17
Table 4 – Fuse-base rated insulation levels – Series I .18
Table 5 – Fuse-base rated insulation levels – Series II .19
Table 6 – Limits of temperature and temperature rise for components and materials.21
Table 7 – Maximum permissible switching voltages .22
Table 8 – Maximum permissible switching voltages for certain fuse-links of small
current ratings.23
Table 9 – Standard values of rated TRV – Series I.24
Table 10 – Standard values of rated TRV – Series II.25
Table 11 – Mechanical characteristics of strikers.28
Table 12 – Electrical connection to the test circuit – Conductor sizes .34
Table 13 – Breaking tests – Parameters .38
Table 14 – TRV for Test Duty 2 – Series I.40
Table 15 – TRV for Test Duty 2 – Series II.41
Table 16 – Breaking test requirements for fuse-links of a homogeneous series .49
Table F.1 – Temperature limits extracted from Table 6 .77

– 6 – 60282-1 © IEC:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
HIGH-VOLTAGE FUSES –
Part 1: Current-limiting fuses

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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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2) The formal decisions or agreements of 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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 60282-1 has been prepared by subcommittee 32A: High-voltage
fuses, of IEC technical committee 32: Fuses.
This seventh edition cancels and replaces the sixth edition published in 2005. The changes
introduced by this new edition are only editorial.
The text of this standard is based on the following documents:
FDIS Report on voting
32A/274/FDIS 32A/277/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.

60282-1 © IEC:2009 – 7 –
A list of all parts of IEC 60282 series, under the general title High-voltage fuses, can be found

on the IEC website.
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.
– 8 – 60282-1 © IEC:2009
HIGH-VOLTAGE FUSES –
Part 1: Current-limiting fuses

1 General
1.1 Scope
This part of IEC 60282 applies to all types of high-voltage current-limiting fuses designed for
use outdoors or indoors on alternating current systems of 50 Hz and 60 Hz and of rated
voltages exceeding 1 000 V.
Some fuses are provided with fuse-links equipped with an indicating device or a striker. These
fuses come within the scope of this standard, but the correct operation of the striker in
combination with the tripping mechanism of the switching device is outside the scope of this
standard; see IEC 62271-105.
1.2 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 60060-1:1989, High-voltage test techniques – Part 1: General definitions and test
requirements
IEC 60071-1:2006, Insulation co-ordination – Part 1: Definitions, principles and rules
IEC 60085:2007, Electrical insulation – Thermal evaluation and designation
IEC 60265-1:1998, High-voltage switches – Part 1: Switches for rated voltages above 1 kV and
less than 52 kV
IEC 60549:1976, High-voltage fuses for the external protection of shunt power capacitors
IEC 60644:1979, Specification for high-voltage fuse-links for motor circuit applications
IEC/TR 60787:2007, Application guide for the selection of high-voltage current-limiting fuse-

links for transformer circuits
IEC 62271-105:2002, High-voltage switchgear and controlgear – Part 105: Alternating current
switch-fuse combinations
ISO 148-2, Metallic materials – Charpy pendulum impact test – Part 2: Verification of test
machines
ISO 179 (all parts), Plastics – Determination of Charpy impact properties
2 Normal and special service conditions
2.1 Normal service conditions
Fuses complying with this standard are designed to be used under the following conditions.

60282-1 © IEC:2009 – 9 –
a) The maximum ambient air temperature is 40 °C and its mean measured over a period of

24 h does not exceed 35 °C.
The minimum ambient air temperature is –25 °C.

NOTE 1 The time-current characteristics of fuses will be modified at the minimum and maximum

temperatures.
b) The altitude does not exceed 1 000 m.

NOTE 2 The rated voltages and insulation levels specified in this standard apply to fuses intended for use at

altitudes not exceeding 1 000 m. When fuses incorporating external insulation are required for use at altitudes

above 1 000 m, one or other of the following procedures should be adopted.

a) The test voltages for insulating parts in air should be determined by multiplying the standard test voltages

given in Tables 4 and 5 by the appropriate correction factor given in column (2) of Table 1.
b) The fuses may be selected with a rated voltage which, when multiplied by the appropriate correction factor
given in column (3) of Table 1 is not lower than the highest voltage of the system.
For altitudes between 1 000 m and 1 500 m and between 1 500 m and 3 000 m, the
correction factors can be obtained by linear interpolation between the values in Table 1.
Table 1 – Altitude correction factors – Test voltage and rated voltage
Maximum altitude Correction factor for Correction factor
test voltages referred for rated voltages
m
to sea-level
(1) (3)
(2)
1 000 1,0 1,0
1 500 1,05 0,95
3 000 1,25 0,80
Where the dielectric characteristics are identical at any altitude, no special precautions
need to be taken.
NOTE 3 The rated current or the temperature rise specified in this standard can be corrected for altitudes
exceeding 1 000 m by using the appropriate factors given in Table 2, columns (2) and (3) respectively. Use one
correction factor from columns (2) or (3), but not both, for any one application.
For altitudes between 1 000 m and 1 500 m and between 1 500 m and 3 000 m, the correction factors can be
obtained by linear interpolation between the values in Table 2.
Table 2 – Altitude correction factors – Rated current and temperature rise
Maximum altitude Correction factor Correction factor
m for rated current for temperature rise
(1) (2) (3)
1 000 1,0 1,0
1 500 0,99 0,98
3 000 0,96 0,92
c) The ambient air is not excessively (or abnormally) polluted by dust, smoke, corrosive or
flammable gases, vapour or salt.
d) For indoor installations, the conditions of humidity are under consideration but, in the
meantime, the following figures can be used as a guidance:
– the average value of the relative humidity, measured during a period of 24 h, does not
exceed 95 %;
– the average value of the vapour pressure, for a period of 24 h, does not exceed 22 hPa;
– the average value of the relative humidity, for a period of one month, does not exceed
90 %;
– 10 – 60282-1 © IEC:2009
– the average value of the water vapour pressure, for a period of one month, does not

exceed 18 hPa.
For these conditions, condensation may occasionally occur.

NOTE 4 Condensation can be expected where sudden temperature changes occur in periods of high humidity.

NOTE 5 To withstand the effects of high humidity and occasional condensation, such as breakdown of in-

sulation or corrosion of metallic parts, indoor fuses designed for such conditions and tested accordingly or

outdoor fuses may be used.
NOTE 6 Condensation may be prevented by special design of the building or housing, by suitable ventilation

and heating of the station or by the use of dehumidifying equipment.

e) Vibrations due to causes external to fuses or earth tremors are negligible.

In addition, for outdoor installations,
f) account should be taken of the presence of condensation or rain and rapid temperature
changes;
g) the wind pressure does not exceed 700 Pa (corresponding to 34 m/s wind speed);
h) the solar radiation does not exceed 1,1 kW/m .
2.2 Other service conditions
Fuse-links intended for use at surrounding temperatures (see 3.3.11) above 40 °C are covered
in this standard in Annex E.
2.3 Special service conditions
By agreement between the manufacturer and the user, high-voltage fuses may be used under
conditions different from the normal service conditions given in 2.1. For any special service
condition, the manufacturer shall be consulted.
2.4 Environmental behaviour
Fuses complying with this standard are inert devices during normal service. It is also a
requirement of 5.1.3 that no significant external emission takes place. Therefore, they are
regarded as environmentally safe devices in service and operation.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Electrical characteristics

3.1.1
rated value
value of a quantity used for specification purposes, established for a specified set of operating
conditions of a component, device, equipment, or system
NOTE Examples of rated values usually stated for fuses, voltage, current and breaking current.
[IEV 441-18-35 modified]
3.1.2
rating
set of rated values and operating conditions
[IEV 441-18-36]
60282-1 © IEC:2009 – 11 –
3.1.3
prospective current (of a circuit and with respect to a fuse)

current that would flow in the circuit if the fuse were replaced by a conductor of negligible

impedance
NOTE For the method to evaluate and to express the prospective current, see 6.6.2.1 and 6.6.2.2.

[IEV 441-17-01, modified]
3.1.4
prospective peak current
peak value of a prospective current during the transient period following initiation

NOTE The definition assumes that the current is made by an ideal switching device, i.e. with instantaneous
transition from infinite to zero impedance. For circuits where the current can follow several different paths, for
example polyphase circuits, it further assumes that the current is made simultaneously in all poles, even if only the
current in one pole is considered.
[IEV 441-17-02]
3.1.5
prospective breaking current
prospective current evaluated at a time corresponding to the instant of the initiation of the
breaking process
NOTE For the fuses, this instant is usually defined as the moment of the initiation of the arc during the breaking
process. Conventions relating to the instant of the initiation of the arc are given in 6.6.2.3.
[IEV 441-17-06]
3.1.6
breaking capacity
value of prospective current that a fuse is capable of breaking at a stated voltage under
prescribed conditions of use and behaviour
[IEV 441-17-08, modified]
3.1.7
cut-off current
let-through current
maximum instantaneous value of current attained during the breaking operation of a fuse
NOTE This concept is of particular importance when the fuse operates in such a manner that the prospective peak
current of the circuit is not reached.

[IEV 441-17-12, modified]
3.1.8
pre-arcing time
melting time
interval of time between the beginning of a current large enough to cause a break in the fuse
element(s) and the instant when an arc is initiated
[IEV 441-18-21]
3.1.9
arcing time
interval of time between the instant of the initiation of the arc in a fuse and the instant of final
arc extinction in that fuse
[IEV 441-17-37, modified]
– 12 – 60282-1 © IEC:2009
3.1.10
operating time
total clearing time
sum of the pre-arcing time and the arcing time

[IEV 441-18-22]
3.1.11
Joule integral
I t
integral of the square of the current over a given time interval t – t
0 1
t
I t = itd
∫
t
2 2
NOTE 1 The pre-arcing I t is the I t integral extended over the pre-arcing time of the fuse.
2 2
NOTE 2 The operating I t is the I t integral extended over the operating time of the fuse.
NOTE 3 The energy in joules liberated in 1 Ω of resistance in a circuit protected by a fuse is equal to the value of
2 2
the operating I t expressed in A × s.
[IEV 441-18-23 modified]
3.1.12
virtual time
value of Joule integral divided by the square of the value of the prospective current
NOTE The values of virtual times usually stated for a fuse-link are the values of pre-arcing time and of operating
time.
[IEV 441-18-37 modified]
3.1.13
time-current characteristic
curve giving the time, for example pre-arcing time or operating time, as a function of the
prospective current under stated conditions of operation
[IEV 441-17-13]
3.1.14
cut-off (current) characteristic
let-through (current) characteristic
curve giving the cut-off current as a function of the prospective current, under stated conditions

of operation
NOTE In the case of a.c., the values of the cut-off currents are the maximum values which can be reached
whatever the degree of asymmetry. In the case of d.c., the values of the cut-off current are the maximum values
reached related to the time-constant as specified.
[IEV 441-17-14]
3.1.15
recovery voltage
voltage which appears across the terminals of a fuse after the breaking of the current
NOTE This voltage may be considered in two successive intervals of time, one during which a transient voltage
exists, followed by a second one during which the power frequency or the steady-state recovery voltage alone
exists.
[IEV 441-17-25, modified]
60282-1 © IEC:2009 – 13 –
3.1.16
transient recovery voltage
TRV
recovery voltage during the time in which it has a significant transient character

NOTE 1 The transient recovery voltage may be oscillatory or non-oscillatory or a combination of these depending

on the characteristics of the circuit and the fuse. It includes the voltage shift of the neutral point of a polyphase
circuit.
NOTE 2 The transient recovery voltage in three-phase circuits is, unless otherwise stated, that across the first

fuse to clear, because this voltage is generally higher than that which appears across each of the other two fuses.

[IEV 441-17-26, modified]
3.1.17
power-frequency recovery voltage
recovery voltage after the transient voltage phenomena have subsided
[IEV 441-17-27]
3.1.18
prospective transient recovery voltage (of a circuit)
transient recovery voltage following the breaking of the prospective symmetrical current by an
ideal switching device
NOTE The definition assumes that the fuse, for which the prospective transient recovery voltage is sought, is
replaced by an ideal switching device, i.e. having instantaneous transition from zero to infinite impedance at the
very instant of zero current, i.e. at the "natural" zero. For circuits where the current can follow several different
paths, for example a polyphase circuit, the definition further assumes that the breaking of the current by the ideal
switching device takes place only in the pole considered.
[IEV 441-17-29, modified]
3.1.19
switching voltage
maximum instantaneous value of voltage which appears across the terminals of a fuse during
its operation
NOTE The switching voltage may be the arc voltage or may occur during the time of transient recovery voltage.
[IEV 441-18-31]
3.1.20
minimum breaking current
minimum value of prospective current that a fuse-link is capable of breaking at a stated voltage
under prescribed conditions of use and behaviour

[IEV 441-18-29]
3.1.21
power dissipation (in a fuse-link)
power released in a fuse-link carrying a stated value of current under prescribed conditions of
use and behaviour
NOTE Prescribed conditions of use and behaviour usually include a constant r.m.s. value of current until steady
temperature conditions are reached.
[IEV 441-18-38]
– 14 – 60282-1 © IEC:2009
3.2 Fuses and their component parts

3.2.1
fuse
device that by the fusing of one or more of its specially designed and proportioned

components, opens the circuit in which it is inserted by breaking the current when this exceeds
a given value for a sufficient time. The fuse comprises all the parts that form the complete device

[IEV 441-18-01]
3.2.2
terminal
conducting part of a fuse provided for an electric connection to external circuits
NOTE Terminals may be distinguished according to the kind of circuits for which they are intended (for example,
main terminal, earth terminal, etc.), but also according to their design (for example, screw terminal, plug terminal, etc.).
3.2.3
fuse-base
fuse-mount
fixed part of a fuse provided with contacts and terminals
NOTE The fuse-base comprises all the parts necessary for insulation (see Figure 1).
[IEV 441-18-02]
Terminal
Striker or indicating device
Fuse el
...