IEC 60115-4-10:2023

IEC 60115-4-10 ®
Edition 1.0 2023-12
INTERNATIONAL
STANDARD
Fixed resistors for use in electronic equipment –
Part 4-10: Blank detail specification: Power resistors with axial leads for
through-hole assembly on circuit boards (THT), for general electronic
equipment, classification level G

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IEC 60115-4-10 ®
Edition 1.0 2023-12
INTERNATIONAL
STANDARD
Fixed resistors for use in electronic equipment –

Part 4-10: Blank detail specification: Power resistors with axial leads for

through-hole assembly on circuit boards (THT), for general electronic

equipment, classification level G

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.040.10  ISBN 978-2-8322-7959-5

– 2 – IEC 60115-4-10:2023 © IEC 2023
CONTENTS
FOREWORD . 5
0 Introduction to the template provided by this blank detail specification. 7
0.1 Scope of this blank detail specification . 7
0.2 Function of this blank detail specification . 7
0.3 Identification of the detail specification and the resistor . 8
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 11
4 Characteristics and ratings . 11
4.1 General . 11
4.2 Dimensions . 11
4.3 Ratings . 13
4.4 Resistance range and tolerance on resistance . 15
5 Tests and test severities . 16
5.1 General . 16
5.2 Resistance . 16
5.3 Temperature coefficient of resistance . 17
5.4 Temperature rise . 17
5.5 Endurance at the rated temperature 70 °C . 17
5.6 Endurance at other than rated temperature . 17
5.6.1 Endurance at room temperature . 17
5.6.2 Endurance at a maximum temperature: UCT with category dissipation . 17
5.7 Short-term overload of power resistors. 17
5.7.1 Power film resistors . 17
5.7.2 Wirewound resistors . 18
5.8 Electrostatic discharge (ESD) test . 18
5.9 Visual examination . 18
5.10 Gauging of dimensions . 19
5.11 Detail dimensions . 19
5.12 Robustness . 19
5.12.1 Robustness of terminations . 19
5.12.2 Robustness of the resistor body . 19
5.13 Shock and vibration . 19
5.13.1 Vibration . 19
5.13.2 Shock or bump . 19
5.14 Rapid change of temperature . 19
5.15 Climatic sequence. 20
5.16 Damp heat, steady state test. 20
5.17 Solderability, with lead-free solder . 21
5.18 Solderability, with SnPb solder . 21
5.19 Resistance to soldering heat . 21
5.20 Solvent resistance test . 21
5.21 Insulation resistance . 22
5.22 Voltage proof . 22
5.23 Flammability test . 22
6 Performance requirements. 22

6.1 General . 22
6.2 Limits for change of resistance at tests . 22
6.3 Temperature coefficient of resistance . 23
6.4 Temperature rise . 24
6.5 Visual examination . 24
6.5.1 General visual criteria . 24
6.5.2 Visual criteria after tests . 25
6.5.3 Visual criteria for packaging . 25
6.6 Solderability . 25
6.7 Insulation resistance . 25
6.8 Flammability . 26
7 Marking, packaging and ordering information . 26
7.1 Marking of the component . 26
7.2 Packaging . 26
7.3 Marking of the packaging . 26
7.4 Ordering information . 26
8 Additional information . 27
8.1 General . 27
8.2 Storage and Transportation . 27
8.3 Substrate for assembly . 27
8.4 Soldering process . 27
8.5 Use of cleaning agents or solvents . 27
8.6 Coating or potting after assembly . 28
9 Quality assessment procedures . 28
9.1 General . 28
9.1.1 100 % test . 28
9.1.2 Certificate of Conformity (CoC) . 28
9.1.3 Certified test records of released lots . 29
9.2 Qualification approval . 29
9.3 Maintenance of a qualification approval . 29
9.3.1 Quality conformance inspection . 29
9.3.2 Non-conforming specimen . 29
Annex A (normative) Symbols and abbreviated terms . 41
A.1 Symbols . 41
A.2 Abbreviated terms . 43
Annex B (normative) Reference for visual examination . 44
Annex X (informative) Cross-reference for references to the prior revision of this
specification. 45
Bibliography . 46

Figure 1 – Outline and dimensions . 12
Figure 2 – Lead eccentricity of the wire terminations . 13
Figure 3 – Length of excessive coating on the wire terminations . 13
Figure 4 – Derating curve for power resistors . 15

Table 1 – Styles and dimensions. 12
Table 2 – Climatic categories . 14

– 4 – IEC 60115-4-10:2023 © IEC 2023
Table 3 – Ratings. 14
Table 4 – Temperature coefficients, tolerances and resistance ranges for climatic
category . / . / . . 16
Table 5 – Short-term overload duration . 18
Table 6 – ESD test voltages . 18
Table 7 – Additional cycles of the damp heat, cyclic test . 20
Table 8 – Damp heat, steady state test duration . 20
Table 9 – Limits for change of resistance at tests . 23
Table 10 – Permitted change of resistance due to the variation of temperature . 24
Table 11 – Test schedule for the qualification approval of power resistors . 30
Table 12 – Test schedule for quality conformance inspection of power resistors . 35
Table X.1 – Cross reference for references to clauses . 45

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIXED RESISTORS FOR USE IN ELECTRONIC EQUIPMENT –

Part 4-10: Blank detail specification:
Power resistors with axial leads
for through-hole assembly on circuit boards (THT),
for general electronic equipment, classification level G

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, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). 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. 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 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 IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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
members of its technical committees and IEC National Committees for any personal injury, property damage or
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch or
www.iso.org/patents. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 60115-4-10 has been prepared by IEC technical committee 40: Capacitors and resistors
for electronic equipment. It is an International Standard.
This first edition cancels and replaces IEC 60115-4-1:1983. This edition constitutes a technical
revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) it employs the product classification based on application requirements as defined in the
generic specification IEC 60115-1:2020;

– 6 – IEC 60115-4-10:2023 © IEC 2023
b) it permits the specification additional dimensional requirements concerning the eccentricity
of termination wires and the coating extending onto wires;
c) it provides for a tabulated presentation of resistance ranges in relationship to the
temperature coefficient and the tolerance;
d) it supports solderability testing for both, traditional lead-bearing soldering and up-to-date
lead-free soldering, as required;
e) it introduces a test for the specimens’ robustness to electrostatic discharge if required;
f) it introduces a test for the specimens’ resistance to solvents if required;
g) it introduces a test for the flammability of the specimens if required;
h) it employs consistent stability requirements grouped in stability classes;
i) it supports the provision of detailed visual acceptance criteria
j) it includes the requirement for a visual inspection of the primary and proximity packaging;
k) it provides the correlated test schedules for a qualification approval and for subsequent
quality conformance inspections side by side;
l) it employs quality assessment procedures which meet the requirements of a zero-defect
approach, which evades the use of historic AQL levels and the permission of non-conforming
specimens in test groups;
m) it provides for the inclusion of specific visual acceptance criteria, to be applied in addition
to those given in Annex B of the sectional specification IEC 60115-4:2022;
n) furthermore, it employs a new document structure, for which a transition guidance is
provided in Annex X.
The text of this International Standard is based on the following documents:
Draft Report on voting
40/3039/CDV 40/3078/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
A list of all parts in the IEC 60115 series, published under the general title Fixed resistors for
use in electronic equipment, can be found on the IEC website.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
0 Introduction to the template provided by this blank detail specification
COMMENT This introduction is not intended to be copied into the drafted detail specification. Therefore, it is
positioned in front of the conventional document structure and clause numbering range. It nevertheless contains
normative requirements to the drafted detail specification.
0.1 Scope of this blank detail specification
This part of IEC 60115-4 is applicable to the drafting of detail specifications for fixed power
resistors with leads, classified to level G, which is defined in IEC 60115-1:2020, 3.4 for general
electronic equipment.
Another part of IEC 60115-4 provides separate blank detail specifications for the drafting of
detail specifications for fixed power resistors with leads, classified to level P and/or to level R.
Yet other parts of IEC 60115-4 may be issued to provide blank detail specifications for the
drafting of detail specifications for vertical or radial fixed power resistors of other technologies
or of other classification levels.
0.2 Function of this blank detail specification
A blank detail specification is a supplementary document to the sectional specification and
contains requirements for style, layout and minimum contents of detail specifications. Detail
specifications not complying with these requirements shall not be accepted as being in
accordance with IEC specifications nor shall they be described as such.
Detail specifications complying with the requirements of this blank detail specification are a
legitimate basis for the quality assessment of leaded fixed power resistors under an adequate
quality assessment system, e.g. the IEC Quality Assessment System for Electronic Components
(IECQ System), whereas the plain blank detail specification is not a suitable basis.
The detail specification should contain a table of contents prior to the first page of the actual
specification.
In the preparation of the detail specification, the content of IEC 60115-4:2022, 8.2 shall be
taken into account. The detail specification should be written by using the preferred values
given in IEC 60115-4.
Units, graphical symbols and letter symbols shall, whenever possible, be taken from those
specified by the following standards:
– IEC 60027-1, Letter symbols to be used in electrical technology – Part 1: General
– IEC 60617, Graphical symbols for diagrams
– IEC 80000 (all parts), Quantities and units
– ISO 80000 (all parts), Quantities and units
This blank detail specification uses for its purpose two different kinds of notes:
NOTE For notes which give additional information intended to assist the understanding or use of the resulting
document and therefore shall be copied as NOTE into the drafted detail specification. As outlined in the ISO/IEC
directives, these notes shall not contain any requirement, instruction, recommendation or permission.
COMMENT For editorial notes which are intended to aid and direct the specification writer and therefore shall
not be copied into the drafted detail specification. In order to accomplish their function, editorial notes require
the use of instructions, recommendations and permissions addressed to the writer of the detail specification.

– 8 – IEC 60115-4-10:2023 © IEC 2023
0.3 Identification of the detail specification and the resistor
The first page of the detail specification should have a layout starting with a title block as
recommended on the following page.
The numbers in square brackets are editorial references, which are not intended to be copied
into the drafted detail specification, and which correspond to the following information on the
contents which shall be inserted in the indicated positions.
[1] The name of the standardization organization under whose authority the detail
specification is published and, if applicable, the organization from whom the detail
specification is available.
[2] The number allocated to the detail specification by the IEC or by the responsible
standardization organization, together with the date of issue and issue number, as
applicable. Further reference details required by the responsible standardization
organization or quality assessment system may be given here, including an established
mark of conformity, as applicable.
[3] The number and issue date and number, as applicable, of the relevant generic
specification, sectional specification and blank detail specification, where the referenced
issues shall be the most recent issues of the respective specifications.
[4] The title of the detail specification, providing a short description of the type of resistors.
This entry should support the discrimination between similar specifications and should
be suitable for an entry in a register of approvals or in a catalogue of standards. It may
duplicate information given in fields [6] and [7] and in the textual scope in Clause 1.
[5] An outline drawing or illustration of the products.
This entry should aid the easy recognition of the specified resistors and, if possible,
support the discrimination between similar specifications. It may duplicate information
given in Figure 1.
[6] Information on the typical construction of the resistors (where applicable), information of
the specified resistors being insulated or non-insulated (see IEC 60115-1:2020, 3.1.7),
and information on compatibility with a specific soldering process (if applicable, see 8.3).
This entry may duplicate information given in the textual scope in Clause 1.
[7] The classification level of the resistors covered by this detail specification, the level of
quality assessment (Assessment level EZ), and the general level of stability
requirements at performance tests (Stability class).
This information may duplicate information given in the textual scope in Clause 1.
[8] Optional field for table notes.
[9] Statement(s) about the availability of information on components qualified to this detail
specification, if applied within a full quality assessment system.
Example for the use within the IECQ system:
Information about components qualified to this detail specification is available in the
approvals section of the website http://www.iecq.org.

Specification available from: IEC 60115-4-10XX: 20YY
[1] [2]
Electronic components of assessed quality in accordance with:
Generic Specification:   IEC 60115-1:2020
Sectional Specification:  IEC 60115-4:2022
Blanc Detail Specification:  IEC 60115-4-10:2023
[3]
FIXED RESISTORS FOR USE IN ELECTRONIC EQUIPMENT –
Part 4-10XX: Detail specification:
Power resistors with axial leads for through-hole assembly on circuit boards (THT), for general electronic
equipment – classification level G

[4]
Technology info
[5]
Insulated / non-insulated [6]
Outline drawing
Product classification level G
Assessment level EZ [7]
Stability classes .
[8]
COMMENT The remainder of this page is intentionally left empty in order to start Clause 1 on top of the next page.

Information about components qualified to this detail specification is available ….
[9]
– 10 – IEC 60115-4-10:2023 © IEC 2023
FIXED RESISTORS FOR USE IN ELECTRONIC EQUIPMENT –

Part 4-10: Blank detail specification:
Power resistors with axial leads
for through-hole assembly on circuit boards (THT),
for general electronic equipment, classification level G

1 Scope
COMMENT The text of this clause may repeat information already given in some fields of the above title block.
Essential information on the special type of components covered by the drafted detail specification may be added,
preferably at the place marked with "…".
This detail specification specifies the characteristics and ratings of fixed power resistors with
axial leads for through hole assembly (THT) on circuit boards …
...
The resistors covered herein are classified to level G, as defined in IEC 60115-1:2020, 3.4 for
general electronic equipment, typically operated under benign or moderate environmental
conditions, where the major requirement is function. Examples for level G include consumer
products and telecommunication user terminals.
This detail specification is based upon the blank detail specification IEC 60115-4-10:2023.
This detail specification establishes test schedules and performance requirements permitting
the quality assessment of the resistors covered herein according to the quality assessment
procedures specified by IEC 60115-1:2020, Annex Q.
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 60062, Marking codes for resistors and capacitors
IEC 60063, Preferred number series for resistors and capacitors
IEC 60115-1:2020, Fixed resistors for use in electronic equipment – Part 1: Generic
specification
IEC 60115-4:2022, Fixed resistors for use in electronic equipment – Part 4: Sectional
specification: Power resistors for through hole assembly on circuit boards (THT) or for assembly
on chassis
specification: Power resistors with axial leads for through-hole assembly on circuit boards (THT),
for general electronic equipment, classification level G
IEC 60286-1, Packaging of components for automatic handling – Part 1: Tape packaging of
components with axial leads on continuous tapes

IEC 60294, Measurement of the dimensions of a cylindrical component with axial terminations
IEC 60301, Preferred diameters of wire terminations of capacitors and resistors
IEC 61760-1, Surface mounting technology – Part 1: Standard method for the specification of
surface mounting components (SMDs)
IEC 61193-2:2007, Quality assessment systems – Part 2: Selection and use of sampling plans
for inspection of electronic components and packages
…
COMMENT 1 The above list of normative references provides an example and needs to be adapted to the actual
requirements of the drafted detail specification, indicated by the space marked with "…", which however does not
preclude from sorting in proper numerical order.
COMMENT 2 According to the ISO/IEC directives, dated references are required when reference is made to a
specific part of the referenced standard and generally should be applied only in such cases.
COMMENT 3 It is recommended to update any dated references to the most recent revision of the referenced
standard when drafting a detail specification. This involves updating of the dated normative references within the
text of the drafted detail specification.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60115-1 and in
IEC 60115-4, as well as the following, apply.
…
COMMENT Any terms and their respective definitions specifically required for the scope of the drafted detail
specification may be inserted in the space marked with "…", using the specified numbering and format. Otherwise,
the above statement should be reduced to "For the purposes of this document, the terms and definitions given in
IEC 60115-1 and in IEC 60115-4 apply." if no further terms or definitions are required in the drafted detail
specification.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
4 Characteristics and ratings
4.1 General
Various parameters of this component are precisely defined in this specification. Unspecified
parameters can vary from one component to another.
4.2 Dimensions
The shape and dimensions of the resistors covered by this specification are shown in Figure 1,
with the specific styles and their respective dimensions given in Table 1. Other shapes are
permissible within the given dimensions.

– 12 – IEC 60115-4-10:2023 © IEC 2023

Figure 1 – Outline and dimensions
COMMENT 1 See IEC 60115-4:2022, 8.2.1.
COMMENT 2 The details shown in Figure 1 may repeat information already given in some fields of the title block
above. Figure 1 in particular needs to define all dimensions intended to be verified by measurements, which generally
includes those dimensions to be specified in Table 1.
Table 1 – Styles and dimensions
g f
Style Dimensions Mass
b c d e
a
D L d l m
Metric X Y
min
mm mm mm mm mg
a
Historical style code, for information only.
b
the body diameter of the resistor D shall be gauged as specified in IEC 60294, see IEC 60115-4:2022 5.3.11.
c
the body length of the resistor L shall be gauged and measured according to IEC 60294, see
IEC 60115-4:2022, 5.3.11 and 5.3.12 respectively.
d
Nominal diameter of the lead-wires d, with permissible tolerances according to IEC 60301.
e
the minimum lead length l for products in tape packaging according to IEC 60286-1 applies to the length of
min
the free sections of lead-wire between the resistor body and each tape. For untapped resistors it applies to
the length of each lead-wire.
f
for information only.
g.
For products which have their origin in the imperial system of units, the inch dimensions can be given
additionally for information, presented in square brackets.

COMMENT 3 See IEC 60115-4, 2022, 8.2.2.
COMMENT 4 The metric style designation is the normative designation used in all other places throughout this
detail specification, see IEC 60115-4:2022, 4.2.1.1. Column X is an optional column for additional style information,
e.g. for traditional alphabetic designations, which generally need to be marked with a respective footnote, e.g. as
"Historical style code, for information only".
COMMENT 5 The dimensions for body diameter D, body length L, lead-wire diameter d and minimum free lead
length l are given as example based on the requirements for axial leaded resistors with cylindrical body and need
min
to correspond to the dimensions identified in Figure 1. The choice of specified dimensions needs to be adapted to
the actual requirements of the drafted detail specification and the shape of products covered therein. The dimensions
may be given in the format of nominal values plus tolerance, or by stating permissible minimum and maximum values.
Columns for additional dimensions may be inserted as required.
COMMENT 6 Column Y represents one or more optional column(s) for the prescription of an additional dimension,
e.g. the permissible lead eccentricity and/or the permissible length of excessive coating on the leads, as required.
COMMENT 7 The specified minimum lead length should consider the variety of inside tape spacing specified as
dimension B by IEC 60286-1, plus the permissible window for the lateral resistor body location, given there as
dimension K.
COMMENT 8 The component mass is not intended to be verified by an inspection procedure. It should be given as
the maximum mass of a single component and should be marked with a respective footnote as "For information only".
The wire terminations of the resistor shall emerge concentrically from the end faces of the
resistor body, see IEC 60115-4:2022, 4.2.1.4 with IEC 60115-4:2022, Figure 9. The real
eccentricity e, as shown in Figure 2, shall not exceed the limit given in Table 1. For gauging of
the lead eccentricity, the effective eccentricity e’ should be used, see IEC 60115-4:2022, 4.2.1.4.

Figure 2 – Lead eccentricity of the wire terminations
COMMENT 9 The above paragraph and figure are optional and given as an example for the specification of a
permissible lead eccentricity. If this specification is used in the drafted detail specification, a suitable method for
gauging and/or measuring of the lead eccentricity needs to be described, e.g. in the respective subclauses of
Clause 5. Alternatively, the deletion of this paragraph and figure will result in the need to update the numbering of
subsequent figures accordingly.
The resistor shall be properly coated in order to provide a suitable protection against
mechanical, electrical and climatic influences, e.g. by means of a conformal lacquer coating. It
is typical for such coating to also cover the end faces of the resistor body, which can lead for
some amount of excessive coating to spread onto the leads, see IEC 60115-4:2022, 4.2.1.2
and Figure 7. The length of excessive coating c, as shown in Figure 3, shall not exceed the limit
given in Table 1.
Figure 3 – Length of excessive coating on the wire terminations
COMMENT 10 The above paragraph and figure are optional and given as an example for the specification of a
permissible length of excessive coating on the wire terminations. If this specification is used in the drafted detail
specification, a suitable method for gauging and/or measuring of the length of excessive coating needs to be
described, e.g. in the respective subclauses of Clause 5. Alternatively, the deletion of this paragraph and figure will
result in the need to update the numbering of subsequent figures accordingly.
4.3 Ratings
The climatic categories applied in this detail specification are given in Table 2.

– 14 – IEC 60115-4-10:2023 © IEC 2023
Table 2 – Climatic categories
Climatic category
LCT / UCT / duration
... / ... / ...
... / ... / ...
COMMENT 1 See IEC 60115-4:2022, 8.2.3. and 4.3.
COMMENT 2 Table 2 may be amended with a column showing the key parameter to which different climatic
categories are allocated in the purpose of discrimination, e.g. the applied stability classes.
The upper category temperature (UCT), which is used for test procedures, should be lower than
the maximum element temperature (MET).
Table 3 – Ratings
Limiting element
Rated Insulation voltage
Style X voltage
dissipation DC or AC peak
DC or AC RMS
P U U
70 max ins
W V V
NOTE For insulated resistors, the insulation voltage U is verified with a test duration of one minute. However,
ins
long time insulation properties can be affected by the influence of moisture, organic material and electrical field
across the insulating layer(s). For non-insulated resistors, this is the max voltage against ambient.

COMMENT 3 See IEC 60115-4:2022, 8.2.6, 8.2.7 and 8.2.8.
COMMENT 4 Column X is an optional column for additional information, e.g. an additional rated dissipation at
another ambient temperature than the rated temperature 70 °C. Such information should however only be presented,
if it is a traditionally well-established information.
COMMENT 5 The insulation voltage shall not be specified lower than the peak value of the AC voltage that can be
applied continuously to the resistors and therefore shall not be rated less than U = 1,42 × U . The insulation
ins max
voltage is not an applicable rating for non-insulated resistors, therefore the entry in this column shall be "n/a" and
the note of Table 3 shall be omitted in detail specifications drafted for non-insulated resistors.
COMMENT 6 Different sets of ratings may be assigned to variations of another parameter, e.g. climatic categories
or stability classes. Then such different sets of ratings should be given in separate tables which need to be clearly
assigned to the relevant parameter(s). According to the ISO/IEC directives, such duplicate tables need to be titled
with subsequent numbers as required, which will result in the need to update the numbering of subsequent tables
accordingly.
The permissible dissipation of resistors covered by this detail specification is the rated
dissipation as given in Table 3, which is derated for an ambient temperature above the rated
temperature 70 °C according to the diagram in Figure 4.

Figure 4 – Derating curve for power resistors
COMMENT 7 See IEC 60115-4:2022, 8.2.6.
COMMENT 8 The scale of derated dissipation may be given as absolute value in Watt or relative in percent as a
fraction of the rated dissipation P .
COMMENT 9 A larger area of operation or permissible temperature rise may be given by the detail specification,
provided it includes all the area given in Figure 4.
4.4 Resistance range and tolerance on resistance
Table 4 gives the combinations of temperature coefficient, tolerance on resistance and
resistance range which can be approved in climatic category . / . / . according to this detail
specification.
COMMENT 1 The above paragraph needs to be adapted
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