IEC 60068-2-77:1999

INTERNATIONAL
IEC
STANDARD
60068-2-77
First edition
1999-01
Environmental testing –
Part 2-77:
Tests – Test 77 – Body strength and impact shock
Essais d’environnement –
Partie 2-77:
Essais – Essai 77 – Résistance du corps
et résistance au choc par impact

Reference number
Numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series.
Consolidated publications
Consolidated versions of some IEC publications including amendments are

available. For example, edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the
base publication, the base publication incorporating amendment 1 and the base

publication incorporating amendments 1 and 2.

Validity of this publication
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology.
Information relating to the date of the reconfirmation of the publication is available
in the IEC catalogue.
Information on the subjects under consideration and work in progress undertaken by
the technical committee which has prepared this publication, as well as the list of
publications issued, is to be found at the following IEC sources:
• IEC web site*
• Catalogue of IEC publications
Published yearly with regular updates
(On-line catalogue)*
• IEC Bulletin
Available both at the IEC web site* and as a printed periodical
Terminology, graphical and letter symbols
For general terminology, readers are referred to IEC 60050: International
Electrotechnical Vocabulary (IEV).
For graphical symbols, and letter symbols and signs approved by the IEC for
general use, readers are referred to publications IEC 60027: Letter symbols to be
used in electrical technology, IEC 60417: Graphical symbols for use on equipment.
Index, survey and compilation of the single sheets and IEC 60617: Graphical symbols
for diagrams.
* See web site address on title page.

INTERNATIONAL
IEC
STANDARD
60068-2-77
First edition
1999-01
Environmental testing –
Part 2-77:
Tests – Test 77 – Body strength and impact shock
Essais d’environnement –
Partie 2-77:
Essais – Essai 77 – Résistance du corps
et résistance au choc par impact

 IEC 1999  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http://www.iec.ch
Commission Electrotechnique Internationale
PRICE CODE
L
International Electrotechnical Commission
For price, see current catalogue

– 2 – 60068-2-77 © IEC:1999(E)

CONTENTS
Page
FOREWORD . 3

Clause
1 Scope and object . 4

2 Normative reference. 4

3 Terms and definitions. 4
4 Test methods. 4
4.1 Body strength. 4
4.2 Impact shock. 5
5 Test.5
5.1 Equipment. 5
5.2 Preconditioning. 5
5.3 Initial measurements . 5
5.4 Test procedure. 6
5.5 Recovery. 6
5.6 Final measurement. 6
6 Information to be given in the relevant specification . 6
Figures. 7
Annex A (informative) – Bibliography . 11

60068-2-77 © IEC:1999(E) – 3 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

_________
ENVIRONMENTAL TESTING –
Part 2-77: Tests – Test 77: Body strength and impact shock

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization
for Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60068-2-77 has been prepared by IEC technical committee 50:
Environmental testing, and is published by IEC technical committee 91: Surface mounting
technology.
The text of this standard is based on the following documents:
FDIS Report on voting
91/155/FDIS 91/162/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.
Annex A is for information only.

– 4 – 60068-2-77 © IEC:1999(E)

ENVIRONMENTAL TESTING –
Part 2-77: Tests – Test 77: Body strength and impact shock

1 Scope and object
This part of IEC 60068 provides test methods applicable to surface mounting devices (SMDs)

made of glass or sintered materials such as capacitors, resistors and inductors incorporating

ferrites. Two test methods exist: body strength and impact shock.
The object of both tests is to evaluate the mechanical stresses applied to SMDs during and
after mounting; these tests look at different mechanical stresses. The relevant component
specification shall specify which test method or methods are applicable.
2 Normative reference
The following normative document contains provisions which, through reference in this text,
constitute provisions of this part of IEC 60068. At the time of publication, the edition indicated
was valid. All normative documents are subject to revision, and parties to agreements based
on this part of IEC 60068 are encouraged to investigate the possibility of applying the most
recent edition of the normative document indicated below. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60194:—, Terms and definitions for printed circuits
3 Terms and definitions
For the purpose of this part of IEC 60068, the terms and definitions given in IEC 60194 apply.
4 Test methods
4.1 Body strength
This test evaluates the strength of the body of the SMD against external static forces which are
applied to them during mounting, in the direction perpendicular to the printed board on which
the SMDs are mounted.
NOTE – The test evaluates the sturdiness of the body of the SMDs and not the adhesive strength at the interface
between the termination and solder of the body. These latter tests are described in IEC 60068-2-21.
This test simulates the static force applied to SMDs during picking up and centering in a
placement process with a rather slow speed mounting machine in which the forces are mainly
of a static nature.
A static force can have a different influence on a device from that of a dynamic force, whose
effects can be evaluated by a test separately described as an impact shock test. This simulates
the mechanical stress applied to the SMDs, during and after mounting the SMDs on a printed
board. This test shall be referred to in the relevant detail specification.

60068-2-77 © IEC:1999(E) – 5 –

4.2 Impact shock
This test evaluates the physical resistance of SMDs against impact shock. This test simulates

the dynamic forces applied by picking and placing tools on a high speed mounting machine.

The influence of a dynamic force on a device can differ from the influence of a static force.

This test shall be referred to in the relevant detail specification.

5 Test
5.1 Equipment
a) Body strength equipment
The equipment shall be able to apply the specified force to the specimen and maintain the
test load for the specified duration. The length (L) of the tip of the pushing tool shall be
wider than the width (W) of the specimen under test. Unless otherwise specified in the
relevant specification, the shape of the tip of the pushing tool shall be chamfered with a
radius of 0,5 mm. The thickness of the pushing tool is not specified (see figure 1). If this
specification cannot be applied due to the shape or construction of the specimen under test
or for any other reason, the shape of the pushing tool shall be specified in the relevant
specification.
b) Impact shock equipment
The equipment shall be able to apply the specified potential energy to the specimen. The
principle of the equipment is given in figure 4. The potential energy is given by the following
formula:
–7
E (J) = m(g) g h (cm) 10
p
where
E is the potential energy;
p
m is the load (weight of collet, shaft and additional weight);
g is the gravity;
h is the height.
The equipment shall be capable of generating a specified impact energy to a specimen by
dropping a load (collet and weight) (see figure 5). No apparent friction shall be experienced
when the collet and weight are dropped. The material of the base of the equipment shall be
made of metal in excess of 1 cm thick, having a sufficiently larger area than the specimen to be
tested and weighing more than 2 kg. There shall be no material under the base which might
reduce the impact energy, such as an elastomer sheet. The equipment shall be placed on a

concrete floor or equivalent rigid structure. The construction and dimensions of the specimen
holding jig shall be given in the relevant specification.
5.2 Preconditioning
Specimens which need preconditioning shall be pretreated in accordance with the relevant
specification.
5.3 Initial measurements
Visual inspection of the specimen shall be made with the assistance of a magnification of at
least 10× under adequate lighting (e.g. 2 000 lx). If specified in the relevant specification,
electrical and/or mechanical characteristics shall be measured.

– 6 – 60068-2-77 © IEC:1999(E)

5.4 Test procedure
5.4.1 Test method 1: body strength

Testing shall include the following steps.

a) Unless otherwise specified in the relevant specification, the specimen shall be placed on

the supporting base, shown in figures 2 and 3, so that both ends of the specimen are

symmetrically positioned on the supporting base. The test table shall be placed on a plane,
robust platform so that the test results shall not be effected when the load is applied. The

angle of the taper of section "A" in figure 2 shall be greater than 70°, but less than 90°.

b) The shapes and supporting base shall be specified in the relevant specification for different
types of SMDs. Two typical examples are given in figures 2 and 3.
c) Apply pressure to the centre of the specimen, using the pushing tool shown in figures 2
and 3), to reach the specified load within 5 s and maintain the pressure for (10 ± 1) s. The
load shall be 10 N unless otherwise specified by the relevant specification.
d) Unless otherwise specified, electrical measurements shall be made during the load
application, in accordance with the relevant specification.
5.4.2 Test method 2: impact shock
Testing shall include the following steps.
a) The specimen shall be mounted on the apparatus as shown in figure 5. A dropping load
shall be applied to the centre surface of the specimen from the dropping height, in each of
three directions, X, Y and Z axes, once on each side, as illustrated in figure 6a). If it is
difficult to apply a load in all three directions, due to the shape of the specimen or
termination construction (see figure 6b), refer to the relevant specification.
b) A load (weight of collet, shaft and additional weight) shall be dropped freely onto a
specimen from specified drop height. Additional weight may be added to the shaft, in
accordance with the relevant speci
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