IEC 60077-5:2019

IEC 60077-5 ®
Edition 2.0 2019-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Electric equipment for rolling stock –
Part 5: Electrotechnical components – Rules for HV fuses

Applications ferroviaires – Équipements électriques du matériel roulant –
Partie 5: Composants électrotechniques – Règles pour les fusibles
à haute tension
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IEC 60077-5 ®
Edition 2.0 2019-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Electric equipment for rolling stock –

Part 5: Electrotechnical components – Rules for HV fuses

Applications ferroviaires – Équipements électriques du matériel roulant –

Partie 5: Composants électrotechniques – Règles pour les fusibles

à haute tension
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 45.060.01 ISBN 978-2-8322-7509-2

– 2 – IEC 60077-5:2019 © IEC 2019
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 7
3.1 Components . 7
3.2 Operational characteristics . 8
3.3 Abbreviated terms . 10
4 Classification . 10
4.1 Breaking range . 10
4.2 Utilisation category . 11
5 Characteristics . 11
6 Product information . 12
6.1 Documentation . 12
6.2 Marking . 12
7 Normal service conditions . 12
8 Constructional and performance requirements . 12
8.1 Constructional requirements . 12
8.1.1 General . 12
8.1.2 Fuse-link . 12
8.1.3 Fuse-base . 13
8.1.4 Spring-loaded contacts . 13
8.1.5 External terminals . 13
8.2 Performance requirements . 13
8.2.1 Operating conditions . 13
8.2.2 Temperature limits . 13
8.2.3 Dielectric properties . 13
8.2.4 Rated voltage . 13
8.2.5 Rated current of the fuse-link . 14
8.2.6 Rated current of the fuse-base . 14
8.2.7 Breaking capacity . 14
8.2.8 Time-current characteristics . 14
9 Tests . 14
9.1 Kinds of tests . 14
9.1.1 General . 14
9.1.2 Type tests . 15
9.1.3 Routine tests . 15
9.1.4 Investigation tests . 15
9.2 Tests for the verification of constructional requirements . 15
9.2.1 General . 15
9.2.2 Type tests . 15
9.2.3 Routine tests . 16
9.3 Type tests for the verification of performance requirements . 16
9.3.1 Test sequence . 16
9.3.2 General test conditions . 17

9.3.3 Test sequence for the verification of general performance
characteristics . 18
9.3.4 Description of tests for the fuse-link . 18
9.4 Routine tests for the verification of performance requirements . 22
9.4.1 General . 22
9.4.2 Resistance measurement . 23
Annex A (normative) Connection diagram for temperature rise tests . 24
Annex B (informative) Comparison between “a” and “g” fuse time current
characteristics . 25
Annex C (informative) Diagram of the test circuit for breaking capacity tests . 26
Annex D (informative) Verification of breaking capacity . 27
Bibliography . 29

Figure A.1 – Connection diagram for temperature rise tests . 24
Figure B.1 – Comparison between “a” and “g” fuse time current characteristics . 25
Figure C.1 – Diagram of the test circuit for breaking capacity tests . 26
Figure D.1 – Test circuit calibration . 27
Figure D.2 – Breaking operation when the instant of arc initiation is after the peak
value of the current . 28
Figure D.3 – Breaking operation when the instant of arc initiation is prior to the peak
value of the current . 28

Table 1 – Conventional times for “g” fuse-links . 11
Table 2 – Rated and test voltages for DC fuse-links supplied from the contact line . 14
Table 3 – Sequence of tests for the highest rating of a homogeneous series . 16
Table 4 – Sequence of tests for the lowest rating of a homogeneous series . 17
Table 5 – Sequence of tests for the intermediate ratings of a homogeneous series . 17
Table 6 – Tolerances on test values . 18
Table 7 – Parameters for breaking capacity tests of DC fuse-links . 20
Table 8 – Time constant of the test circuit . 21

– 4 – IEC 60077-5:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS –
ELECTRIC EQUIPMENT FOR ROLLING STOCK –

Part 5: Electrotechnical components –
Rules for HV 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
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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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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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
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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 60077-5 has been prepared by IEC technical committee 9:
Electrical equipment and systems for railways.
This second edition cancels and replaces the first edition, issued in 2003. It constitutes a
technical revision.
This edition includes the following main technical changes with regard to the previous edition:
a) test method of test duty III for verification of breaking capacity is reviewed.

The text of this International Standard is based on the following documents:
FDIS Report on voting
9/2539/FDIS 9/2555/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
This document should be read in conjunction with IEC 60077-1 and IEC 60077-2.
A list of all parts in the IEC 60077 series, published under the general title Railway
applications – Electric equipment for rolling stock, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 60077-5:2019 © IEC 2019
RAILWAY APPLICATIONS –
ELECTRIC EQUIPMENT FOR ROLLING STOCK –

Part 5: Electrotechnical components –
Rules for HV fuses
1 Scope
The purpose of this part of IEC 60077 is to give additional or amended rules for high voltage
(HV) fuses as a supplement to those given by IEC 60077-2.
NOTE 1 In this document the term high voltage fuses is used in the context of the voltages used in the field of
railway rolling stock.
The high voltage fuses concerned are those connected into power and/or auxiliary circuits.
The nominal voltage of these circuits lies between 600 V DC and 3 000 V DC, according to
IEC 60850. These fuses can also be used in auxiliary AC circuits up to a nominal voltage of
1 500 V.
NOTE 2 Certain of these rules, after agreement between the user and the manufacturer, are used for fuses
installed on vehicles other than rail rolling stock such as mine locomotives, trolleybuses, etc.
This document together with IEC 60077-2 states specifically:
a) the characteristics of the fuses;
b) the service conditions with which the fuses comply with reference to:
– operation and behaviour in normal service;
– operation and behaviour in case of short circuit;
– dielectric properties.
c) the tests intended for confirming the compliance of the fuse with the characteristics under
the service conditions and the methods adopted for these tests;
d) the information marked on, or given with, the fuse.
This document does not cover parallel connection of fuses.
During preparation of this document, IEC 60269-1 and IEC 60282-1 have been considered
and their requirements have been kept as far as possible.
This document makes reference to the general rules for electrotechnical components given in
IEC 60077-2, but for general conditions reference is made directly to IEC 60077-1.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements 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 60077-1:2017, Railway applications – Electric equipment for rolling stock – Part 1:
General service conditions and general rules

IEC 60077-2:2017, Railway applications – Electric equipment for rolling stock – Part 2:
Electrotechnical components – General rules
IEC 60269-1:2006, Low-voltage fuses – Part 1: General requirements
IEC 60269-1:2006/AMD1:2009
IEC 60269-1:2006/AMD2:2014
IEC 60282-1:2009, High-voltage fuses – Part 1: Current-limiting fuses
IEC 60282-1:2009/AMD1:2014
IEC 61373, Railway applications – Rolling stock equipment – Shock and vibration tests
ISO 3, Preferred numbers – Series of preferred numbers
3 Terms, definitions and abbreviated terms
For the purposes of this document, the terms and definitions given in Clause 3 of
IEC 60077-1:2017 and Clause 3 of IEC 60077-2:2017, and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 Components
NOTE For terminologies of a fuse, see also Figure 1 in IEC 60282-1:2009/AMD1:2014.
3.1.1
fuse
device that, by the fusing of one or more of its specifically 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
Note 1 to entry: The fuse comprises all the parts that form the complete device.
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-01, modified – The second sentence has
been changed to Note 1 to entry.]
3.1.2
fuse-link
part of a fuse (including the fuse-element(s)) intended to be replaced after the fuse has
operated
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-09]
3.1.3
fuse-element
part of the fuse-link designed to melt under the action of current exceeding some definite
value for a definite period of time
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-08]
3.1.4
fuse-base
fixed part of a fuse provided with contacts and terminals

– 8 – IEC 60077-5:2019 © IEC 2019
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-02]
3.1.5
indicating device,
part of a fuse provided to indicate whether the fuse has operated
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-17]
3.1.6
open box type fuse
fuse installed in an open box equipped with an arc chute in order to reduce arc quickly
3.1.7
homogeneous series,
series of fuse-links, deviating from each other only in such characteristics that, for a given
test, the testing of one or a reduced number of particular fuse-link(s) of that series can be
taken as representative for all the fuse-links of the homogeneous series
Note 1 to entry: The relevant publications specify the characteristics by which the fuse-links of a homogeneous
series may deviate, the particular fuse-links to be tested and the specific test concerned.
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-34, modified – “may” has been replaced
with “can”.]
3.2 Operational characteristics
3.2.1
prospective current,
current that would flow in the circuit if each pole of the switching device or the fuse were
replaced by a conductor of negligible impedance
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-17-01, modified – Note has been deleted.]
3.2.2
prospective peak current
peak value of a prospective current during the transient period following initiation
Note 1 to entry: This term is commonly associated with short-circuit conditions.
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-17-02, modified – Note to entry has been
replaced.]
3.2.3
pre-arcing 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
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-21]
3.2.4
arcing time,
interval of time between the instant of the initiation of the arc in a pole or a fuse and the
instant of final arc extinction in that pole or that fuse
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-17-37]

3.2.5
operating time
sum of the pre-arcing time and the arcing time
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-22]
3.2.6
arc voltage,
instantaneous value of voltage which appears across the terminals of a fuse during the arcing
time
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-30]
3.2.7
peak arc voltage,
maximum instantaneous value of voltage which under prescribed conditions appears across
the terminals of a fuse during the arcing time
Note 1 to entry: After extinction of the arc, an overvoltage (transient recovery voltage) may be present across the
terminals. The value of this will depend on the circuit characteristics and the fuse. This overvoltage is not part of
the peak arc voltage (see Figure D.2 and Figure D.3).
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-17-30, modified – “a pole of a switching
device” has been replaced with “a fuse”. Note 1 to entry has been added.]
3.2.8
DC steady-state recovery voltage
recovery voltage in a DC circuit after the transient voltage phenomena have subsided,
expressed by the mean value where ripple is present
Note 1 to entry: This is shown as B and B in Figure D.2 and Figure D.3.
1 2
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-17-28, modified – Note 1 to entry has been
added.]
3.2.9
peak let-through current
maximum instantaneous value of current attained during the operation of a fuse
3.2.10
joule integral
I t
integral of the square of the current over a given time interval
t
2 2
I t= i dt
∫
t
2 2
Note 1 to entry: The pre-arcing I t is the I t integral extended over the pre-arcing time of the fuse.
2 2
Note 2 to entry: The operating I t is the I t integral extended over the operating time of the fuse.
Note 3 to entry: The energy in joules liberated in one ohm of resistance in a circuit protected by a fuse is equal to
2 2
the value of the operating I t expressed in A s.
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-23]

– 10 – IEC 60077-5:2019 © IEC 2019
3.2.11
time-current characteristic
curve giving the time, e.g. pre-arcing time or operating time, as a function of the prospective
current under stated conditions of operation
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-17-13]
3.2.12
conventional non-fusing current
value of current specified as that which the fuse-link is capable of carrying for a specified time
(conventional time) without melting
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-27]
3.2.13
conventional fusing current
value of current specified as that which causes operation of the fuse-link within a specified
time (conventional time)
[SOURCE: IEC 60050-441:1984/AMD1:2000, 441-18-28]
3.2.14
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 1 to entry: The rated values usually stated for fuses are voltage, current, breaking capacity and power
dissipation.
[SOURCE: IEC 60050-151:2001, 151-16-08, modified – Note 1 to entry has been added.]
3.3 Abbreviated terms
AC Alternating Current
DC Direct Current
HV High Voltage
4 Classification
4.1 Breaking range
Fuse-links are classified according to whether they are:
a) “g” fuse-link: with a full range breaking capacity, i.e. capable under specified conditions of
breaking all currents which cause melting of the fuse-element up to its rated breaking
capacity;
b) “a” fuse-link: with a partial range breaking capacity, i.e. capable of breaking under
specified conditions all currents between their minimum breaking capacity and their rated
breaking capacity. They may be used in conjunction with another switching device where
protection is required against overcurrent below their minimum breaking capacity.
NOTE 1 Comparison between “a” and “g” fuse time current characteristics is shown in Figure B.1 of Annex B.
NOTE 2 Examples of “a” fuse-link protection can be those for protection of semiconductor devices, motors, etc.

4.2 Utilisation category
Fuse-links may be categorised according to whether they are to be subjected in normal
service to:
– current values which do not exceed their continuous rating;
– current values which briefly exceed their continuous rating on a regular basis, such as
when starting a rotating machine;
– current values which do not exceed their continuous rating but which are switched or
change significantly in a frequently repeated pattern;
or they have to provide a special protection as, for example:
– semiconductor conditions, where fast action is required in order to limit the peak let-
through current and the operating I t;
– provide a time delayed operation.
5 Characteristics
The characteristics of a fuse shall be stated in terms of the following:
– rated voltage(s) DC and/or AC;
);
– rated current (I
n
– rated frequency;
– rated breaking capacity;
– breaking range;
– rated power dissipation;
– time-current characteristics. The conventional times and currents for “g” fuse-links are
given in Table 1;
– overload capability;
2 2 2
– I t characteristics (minimum pre-arcing I t and maximum operating I t);
– peak let-through current related to prospective current and time constant;
– current rating correction factors versus ambient temperature;
– peak arc voltage related to operating voltage;
– rated insulation voltage (U ) for fuse-bases;
Nm
– rated impulse voltage (U ) for fuse-bases.
Ni
When presented graphically, the I t characteristics shall be given with prospective current as
abscissa and I t values as ordinate. Logarithmic scales shall be used on both co-ordinate
axes.
Table 1 – Conventional times for “g” fuse-links
Rated current Specified time
(conventional time)
A h
I ≤ 63 1
n
63 < I ≤ 160
n
160 < I ≤ 400
n
I > 400
n
– 12 – IEC 60077-5:2019 © IEC 2019
6 Product information
6.1 Documentation
This information shall be given in the manufacturer's catalogue or manual.
6.1 of IEC 60077-2:2017 applies, supplemented by the following:
– rated voltage;
– rated current;
– rated breaking capacity and time constant;
– suitable applications (see 4.2);
2 2 2
– I t characteristics (minimum pre-arcing I t and maximum operating I t);
– correction factors for current rating versus ambient temperature, varying load and overload;
– physical dimensions;
– special instructions for storage, installation, maintenance, if applicable.
6.2 Marking
Fuse-links and fuse-bases shall possess durable and legible nameplates or engraved
markings in accordance with 6.2 of IEC 60077-2:2017.
For the open box type fuse nameplates or engraved markings shall be placed on the box.
The markings of the fuse-link and fuse-base shall include the following data:
– manufacturer's name or trade mark;
– manufacturer's type designation;
– rated voltage (DC and/or AC);
– rated current.
7 Normal service conditions
These conditions are given in Clause 7 of IEC 60077-1:2017.
8 Constructional and performance requirements
8.1 Constructional requirements
8.1.1 General
In addition to the requirements of 8.1 of IEC 60077-2:2017, the fuse shall comply with the
following requirements.
8.1.2 Fuse-link
The fuse-link shall be sufficiently robust so that there shall be no damage to the surroundings
e.g. by permanent arcing, flashover or any ejection of flames or materials during operation.
NOTE 1 For further details, see 8.5.8 of IEC 60269-1:2006/AMD1:2009/AMD2:2014.
It shall be possible to replace the fuse-links easily.
NOTE 2 For further details of replacement, see 7.1.1 of IEC 60269-1:2006/AMD1:2009/AMD2:2014.

8.1.3 Fuse-base
The fuse-base shall incorporate contacts which ensure that the connections to the fuse-link
are adequate under all conditions of thermal cycling, vibration and shock during normal
service and during the application of the electro-dynamic forces when the fuse-link is
rupturing overload or short-circuit currents up to its rated breaking capacity value.
8.1.4 Spring-loaded contacts
Where the fuse-base incorporates spring-loaded contacts for electrical connection and
mechanical retention of the fuse-link, these contacts shall withstand 100 cycles of insertions
and removals of the fuse-link without deterioration of the electrical and mechanical properties.
8.1.5 External terminals
Terminals for external connection to the fuse-base shall provide a constant clamping force
unaffected by variation in current through them. They shall be capable of enduring multiple
connection and disconnection of the external conductors without deterioration. Terminal screw
thread shall have a minimum size of M5.
Terminals shall be such that they cannot turn or be displaced when the connecting screws are
tightened, and such that the conductors cannot be displaced.
The parts gripping the conductors shall be of metal and shall have a shape such that they
cannot unduly damage the conductors.
No contact force on connections shall be transmitted through insulating material other than
ceramic, or other material having mechanical characteristics no less suitable.
NOTE For further information, see 7.1.2 of IEC 60269-1:2006/AMD1:2009/AMD2:2014.
8.2 Performance requirements
8.2.1 Operating conditions
These requirements are given in 8.2.1 of IEC 60077-2:2017.
8.2.2 Temperature limits
These requirements are given in 8.2.2 of IEC 60077-2:2017.
8.2.3 Dielectric properties
Requirements of clearances are given in 8.2.6 of IEC 60077-1:2017.
Requirements of creepage distances are given in 8.2.7 of IEC 60077-1:2017.
8.2.4 Rated voltage
For fuses fed from the contact line, the rated voltage of the fuses shall be in accordance with
Table 2. For fuses not fed from the contact line, the breaking test voltage shall be at least
equal to the highest operational voltage of the circuit in which it is connected.

– 14 – IEC 60077-5:2019 © IEC 2019
Table 2 – Rated and test voltages for DC fuse-links supplied from the contact line
Nominal line voltage Rated voltage of the fuse Breaking test voltage
V V V
600 720 800
750 900 1 000
1 500 1 800 1 950
3 000 3 600 3 900
8.2.5 Rated current of the fuse-link
The rated current for the fuse-link, expressed in amperes (A), should be selected from the
following values:
0,6; 1; 2; 3; 4; 6; 10; 12; 16; 20; 25; 32; 40; 50; 63; 80; 100; 125; 160; 200; 250; 315; 400; 500;
630; 800 and 1 000.
If it is necessary to choose lower values or intermediate values or higher values, these values
should be selected from the series R10 of ISO 3, and in exceptional cases, from R20 or R40
of ISO 3.
8.2.6 Rated current of the fuse-base
The rated current of the fuse-base shall be equal to or greater than that of the relevant fuse-
link and should be selected from the series of rated currents of the fuse-links given in 8.2.5.
8.2.7 Breaking capacity
The fuse-link shall interrupt correctly any current within the range from minimum breaking
capacity up to its rated breaking capacity at the appropriate test voltage given in Table 7. The
peak arc voltage shall not exceed 3 times the test voltage.
For low current ratings (lower than or equal to 6,3 A), the peak arc voltage may reach 4,5
times the test voltage.
8.2.8 Time-current characteristics
The manufacturer shall include in the technical documentation for the fuse-links the time-
current characteristics at (20 ± 5) °C.
9 Tests
9.1 Kinds of tests
9.1.1 General
9.1.1 of IEC 60077-1:2017 applies, except that sampling tests are not applicable.
The tests to verify the characteristics of the fuses are:
– type tests (see 9.1.2);
– routine tests (see 9.1.3);
– investigation tests (see 9.1.4).

9.1.2 Type tests
The type tests comprise the following:
– verification of constructional requirements (see 9.2.2);
– verification of performance requirements (see 9.3).
For the type tests, the number of fuses or fuse-links shall be as indicated in Table 3, Table 4
and Table 5. They shall be randomly selected from the manufacturing production line. In all
tests, the same fuse-base should be used.
The type test results shall be deemed to be compliant if the results of all the type tests listed
in Table 3, Table 4 and Table 5 meet the requirements.
For the type tests, test certificates shall be provided for each fuse-link or fuse tested, to prove
their general compliance with the technical documentation.
9.1.3 Routine tests
Routine tests shall be carried out on each fuse-link and fuse-base.
The routine tests comprise the following:
– verification of constructional requirements (see 9.2.3);
– verification of performance requirements (see 9.4).
The routine test results shall be deemed to be compliant if the results of all the routine tests
listed in 9.2.3 and 9.4 meet the requirements.
9.1.4 Investigation tests
These are supplementary tests to the type tests for a special application. They form the
subject of a programme agreed between the fuse manufacturer and the user, and may
concern:
– the influence of frequent current variation on the operating characteristics;
– the influence of frequent start current surges on the operating characteristics;
– the influence of the circuit time-constant on the behaviour of the fuse during the breaking
capacity tests.
9.2 Tests for the verification of constructional requirements
9.2.1 General
The compliance of the fuse-link and fuse-base with the constructional requirements described
in Clause 8 shall be verified generally in accordance with 9.2 of IEC 60077-1:2017, prior to
the verification of performance requirements as detailed in 9.3 and 9.4.
9.2.2 Type tests
Verification of compliance with the constructional requirements for the type test of both fuse-
link and fuse-base concerns:
– physical properties. A check shall be made that the fuse conforms to the drawings (e.g.
dimensions, materials, electrical risks, etc.);
– clearance and creepage distances (see 9.3.3.2.1 and 9.3.3.2.3 of IEC 60077-1:2017).

– 16 – IEC 60077-5:2019 © IEC 2019
9.2.3 Routine tests
The verification of compliance with the constructional requirements for the routine test of both
fuse-link and fuse-base concerns visual examination (compliance of the manufacture with the
drawing).
9.3 Type tests for the verification of performance requirements
9.3.1 Test sequence
Type tests are grouped in a number of test sequences as shown in Table 3, Table 4 and
Table 5.
For fuse-links in a homogeneous series:
– the fuse-link having the highest rated current shall be tested according to Table 3;
– the fuse-link having the lowest rated current shall be tested according to Table 4;
– the fuse-link having a current rating between the largest and the lowest current shall be
tested according to Table 5.
For fuse-links which are not part of a homogeneous series, the fuse shall be tested according
to Table 3 and, in addition, the verification of the ability to withstand vibration and shock
according to 9.3.4.5 shall be tested.
For each sequence, the tests should preferably be carried out in the order listed.
A routine test (see 9.1.3) shall be carried out on every fuse-link before the type tests.
Table 3 – Sequence of tests for the highest rating of a homogeneous series
Subclause Test “g” fuse-links “a” fuse-links
number
Number of samples 3 3 2 2 1 1 1 1 1 3 3 2 2 1 1 1 1
9.2.2 Visual inspection (dimensions mm) X X X X X X X X X X X X X X X X X
9.4.2 Resistance measurement X X X X X X X X X X X X X X X X X
9.3.4.1 Temperature rise measurement     X    X
9.3.4.3 Verification of breaking capacity I X     X
9.3.4.3 Verification of breaking capacity I X     X
9.3.4.3 Verification of breaking capacity I  X     X
9.3.4.3 Verification of breaking capacity I  X     X
Verification of time-current
9.3.4.4   X     X
characteristic I
9.3.4.4 Verification of time-current   X     X
characteristic I
9.3.4.4 Verification of time-current    X     X
characteristic I
9.3.4.2 Verification of conventional non-    X
fusing current
9.3.4.2 Verification of conventional fusing    X
current
9.3.4.6 Insertion and extraction     X    X
a
performance
a
9.3.4.7 Verification of dielectric withstand     X    X
a
This test is to be performed on the complete fuse when the fuse-link is used with a fuse-base.

Table 4 – Sequence of tests for the lowest rating of a homogeneous series
Subclause Test “g” fuse-links “a” fuse-links
number
Number of samples 1 3 2 2 1 1 1 1 1 1 3 2 2 1 1 1 1
9.2.2 Visual inspection X X X X X X X X X X X X X X X X X
(dimensions mm)
9.4.2 Resistance measurement X X X X X X X X X X X X X X X X X
9.3.4.1 Temperature rise measurement X     X
9.3.4.3 Verification of breaking capacity I X     X
9.3.4.3 Verification of breaking capacity I  X     X
9.3.4.3 Verification of breaking capacity I  X     X
9.3.4.4 Verification of time-current   X     X
characteristic I
9.3.4.4 Verification of time-current   X     X
characteristic I
9.3.4.4 Verification of time-current    X     X
characteristic I
9.3.4.2 Verification of conventional non-    X
fusing current
9.3.4.2 Verification of conventional    X
fusing current
Verification of ability to withstand
9.3.4.5 X     X
vibration and shock
a
9.3.4.7 Verification of dielectric withstand     X    X
a
This test is to be performed on the complete fuse when the fuse-link is used with a fuse-base.

Table 5 – Sequence of tests for the intermediate ratings of a homogeneous series
Subclause Test “g” fuse-l
...