IEC 61020-1:2009

IEC 61020-1 ®
Edition 2.0 2009-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electromechanical switches for use in electrical and electronic equipment –
Part 1: Generic specification
Interrupteurs électromécaniques pour équipements électriques et
électroniques –
Partie 1: Spécification générique

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IEC 61020-1 ®
Edition 2.0 2009-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electromechanical switches for use in electrical and electronic equipment –
Part 1: Generic specification
Interrupteurs électromécaniques pour équipements électriques et
électroniques –
Partie 1: Spécification générique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XB
CODE PRIX
ICS 31.220.20 ISBN 978-2-88910-401-7
– 2 – 61020-1 © IEC:2009
CONTENTS
FOREWORD.5

INTRODUCTION.7

1 Scope and object.8

1.1 Scope.8

1.2 Object .8

2 General .8

2.1 Normative references .8

2.2 Units and symbols .10
2.3 Terms and definitions .10
2.4 Preferred values.12
2.4.1 Clearance and creepage distances .12
2.5 Marking .12
3 Quality assessment procedures.12
4 Test and measurement procedures.12
4.1 General .12
4.1.1 Tolerances .13
4.1.2 Preconditioning.13
4.1.3 Mounting .13
4.2 Standard atmospheric conditions.13
4.3 General examination .13
4.3.1 Visual examination .13
4.3.2 Dimensions .14
4.3.3 Dimensions, gauging .14
4.3.4 Mass .15
4.3.5 Functional operation .15
4.3.6 Operating characteristics .16
4.3.7 Contact bounce .18
4.4 Resistance measurements .19
4.4.1 Contact resistance – Millivolt level.19
4.4.2 Contact resistance – Specified current .21
4.4.3 Resistance from actuator to mounting bushing (surface).22
4.4.4 Insulation resistance.23

4.5 Dielectric strength .23
4.5.1 Dielectric strength at standard atmospheric conditions .23
4.5.2 Dielectric strength at low air pressure.24
4.6 Heating .25
4.6.1 Object .25
4.6.2 Method .25
4.6.3 Requirement.26
4.6.4 Details to be specified .26
4.7 Dynamic stress.26
4.7.1 Shock .26
4.7.2 Vibration.27
4.7.3 Contact disturbance.28
4.8 Mechanical strength .28
4.8.1 Robustness of actuator.28

61020-1 © IEC:2009 – 3 –
4.8.2 Robustness of mounting bushing .31

4.8.3 Robustness of screw mounting .31

4.8.4 Robustness of terminations .31

4.9 Mechanical endurance.32

4.9.1 Mechanical endurance – Standard atmospheric conditions .32

4.9.2 Mechanical endurance – Category temperature range .33

4.10 Electrical endurance.33

4.10.1 Electrical endurance – Standard atmospheric conditions .33

4.10.2 Electrical endurance – Upper category temperature.35

4.10.3 Electrical endurance – Category temperature range .36

4.10.4 Electrical endurance – Low air pressure .36
4.10.5 Logic loads (TTL) .37
4.10.6 Low level endurance test .38
4.11 Overload .39
4.11.2 Electrical overload .39
4.11.3 Capacitive load switching .40
4.12 Environmental testing.41
4.12.1 Climatic sequence .41
4.12.2 Damp heat, steady state.43
4.12.3 Rapid change of temperature.44
4.12.4 Mould growth (resistance) .44
4.12.5 Corrosion, industrial atmosphere .45
4.12.6 Dust and sand .46
4.12.7 Contact resistance stability.48
4.13 Soldering.49
4.13.1 Solderability, wetting, solder bath method.49
4.13.2 Solderability, wetting, soldering iron method.50
4.13.3 Solderability, de-wetting .51
4.13.4 Resistance to soldering heat, solder bath method.51
4.13.5 Resistance to soldering heat, soldering iron method .52
4.14 Panel seal .53
4.14.1 Drip – Proof .53
4.14.2 Splash – Proof.53
4.14.3 Immersion .53
4.14.4 Submersion .54

4.15 Enclosure seal.55
4.15.1 Watertight immersion.55
4.15.2 Resilient or hermetic seal .55
4.16 Fluid resistance.56
4.16.1 Immersion in cleaning solvents (marking) .56
4.17 Fire hazard.56
4.18 Capacitance .56
4.18.1 Object .56
4.18.2 Method .56
4.18.3 Requirement.57
4.18.4 Details to be specified .57
4.19 Illumination.57
4.19.1 Chromaticity .57
4.19.2 Transmittancy.57

– 4 – 61020-1 © IEC:2009
4.19.3 Temperature of illuminated surface.58

4.20 Soldering for surface mounting switches .58

4.20.1 Solderability, solder bath method (surface mounting switches) .58

4.20.2 Solderability, reflow method (surface mounting switches) .59

4.20.3 Solderability, soldering iron method (surface mounting switches) .60

4.20.4 Resistance to soldering heat , solder bath method (surface mounting

switches) .60

4.20.5 Resistance to soldering heat, reflow method (surface mounting

switches) .61

4.20.6 Resistance to soldering heat, soldering iron method (surface

mounting switches).62
4.21 Mechanical strength (surface mounting switches).62
4.21.1 Substrate bending (surface mounting switches) .62
4.21.2 Pull-off and push-off (surface mounting switches).63
4.21.3 Shear (surface mounting switches) .64
4.21.4 Body strength (surface mounting switches).64
Annex A (informative) Quality assurance procedures .66
Bibliography.67

Figure 1 – Contact bounce test circuit.18
Figure 2 – Typical trace of contact bounce.19
Figure 3 – Application of forces and torques for test 4.81.30
Figure 4 – Submersion seal enclosure .55

Table 1 – Minimum wire length .25
Table 2 – Torque values for mounting screws .31
Table 3 – Methods proposed for corrosion tests.46
Table 4 – Solderability, Bath method: Test severities (duration and temperature) .50

61020-1 © IEC:2009 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
ELECTROMECHANICAL SWITCHES
FOR USE IN ELECTRICAL AND ELECTRONIC EQUIPMENT –

Part 1: Generic specification
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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) 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 61020-1 has been prepared by subcommittee 23J: Switches for
appliances, of IEC technical committee 23: Electrical accessories.
This second edition cancels and replaces the first edition published in 1991. This second
edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition.
a) The requirements of the IEC 60512 series of standards have been integrated in this
second edition of IEC 61020-1. In particular the test methods, terminology, symbols and
other necessary information concerning switches as specified in IEC 60512 have been
implemented in this standard.
b) Additionally, the following items have been updated with respect to the first edition:
– test methods were reviewed for detailed description;

– 6 – 61020-1 © IEC:2009
– the explanation for the test method of the operating force was rewritten in more detail;

– the test voltage for measurement for contact bounce was reviewed;

– the electrical endurance “ON” duration in the duty cycle was harmonized with

IEC 61058;
– the requirements for fire hazards have been deleted;

– testing methods of surface mounting switches based on the Japanese industrial

standard were added.
The text of this standard is based on the following documents:

FDIS Report on voting
23J/325/FDIS 23J/328/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.
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.
61020-1 © IEC:2009 – 7 –
INTRODUCTION
This generic specification covers the general requirements and test methods for

electromechanical switches with optional quality assurance procedures. It provides the

general requirements and test methods for use in any detail specifications for pushbutton

switches, rotary switches, sensitive switches, toggle switches, and other electromechanical

switches. It also provides guidelines for appropriate quality assurance procedures in Annex A

(informative).
Where it is intended that an electromechanical switch comply with requirements related to

safety, the specific safety requirements are specified in IEC 61058-1.

– 8 – 61020-1 © IEC:2009
ELECTROMECHANICAL SWITCHES
FOR USE IN ELECTRICAL AND ELECTRONIC EQUIPMENT –

Part 1: Generic specification
1 Scope and object
1.1 Scope
This generic specification relates to electromechanical switches intended for use in electrical
and electronic appliances. Switches covered by this specification:
a) are devices which open, close, or change the connection of a circuit by the mechanical
motion of conducting parts (contacts);
b) have a maximum rated voltage of 480 V;
c) have a maximum rated current of 63 A.
This generic specification does not include keyboards and keypads which are intended for use
in information-handling systems. Electromechanical key switches may be included under the
scope of this generic specification.
Switch families shall be described in any detail specifications that will reference this generic
specification.
1.2 Object
The object of this generic specification is to provide consistency in detail specifications for
electromechanical switches by specifying the terminology, symbols, test methods and other
necessary information.
2 General
2.1 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 60027 (all parts), Letter symbols to be used in electrical technology
IEC 60050-581:2008, International Electrotechnical Vocabulary – Part 581: Electromechanical
components for electronic equipment
IEC 60068-1:1988, Environmental testing – Part 1: General and guidance
Amendment 1 (1992)
IEC 60068-2-6:2007, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)
IEC 60068-2-1:2007, Environmental testing – Part 2-1: Tests – Test A: Cold
IEC 60068-2-2:2007, Environmental testing – Part 2-2: Tests – Test B: Dry heat

61020-1 © IEC:2009 – 9 –
IEC 60068-2-10:2005, Environmental testing – Part 2-10: Tests – Test J and guidance: Mould

growth
IEC 60068-2-13:1983, Environmental testing – Part 2-13: Tests – Test M: Low air pressure

IEC 60068-2-14:2009, Environmental testing – Part 2-14: Tests – Test N: Change of

temperature
IEC 60068-2-17:1994, Environmental testing – Part 2-17: Tests – Test Q: Sealing

IEC 60068-2-20:2008, Environmental testing – Part 2-20: Tests – Test T: Test methods for

solderability and resistance to soldering heat of devices with leads
IEC 60068-2-21:2006, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60068-2-30:2005, Environmental testing – Part 2-30: Tests – Test Db: Damp heat, cyclic
(12+12-hour cycle)
IEC 60068-2-42:2003, Environmental testing – Part 2-42: Tests – Test Kc: Sulphur dioxide
test for contacts and connections
IEC 60068-2-43:2003, Environmental testing – Part 2-43: Tests – Test Kd: Hydrogen sulphide
test for contacts and connections
IEC 60068-2-45:1980, Environmental testing – Part 2-45: Tests – Test XA and guidance:
Immersion in cleaning solvents
Amendment 1 (1993)
IEC 60068-2-49:1983, Environmental testing – Part 2-49: Tests – Guidance to Test Kc:
Sulphur dioxide test for contacts and connections
IEC 60068-2-58:1999, Environmental testing Part 2-58: Tests – Tests Td: Test methods for
solderability, resistance to dissolution of metallization and to soldering heat of surface
mounting devices (SMD)
IEC 60068-2-61:1991, Environmental testing – Part 2-61: Test methods – Test Z/ABDM:
Climatic sequence
IEC 60068-2-68:1994, Environmental testing – Part 2-68: Tests – Test L: Dust and sand

IEC 60068-2-78:2001, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat,
steady state
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
Amendment 1 (2001)
IEC 60617, Graphical symbols for diagrams
IEC 61058-1:2000, Switches for appliances – Part 1: General requirements
Amendment 1 (2001)
Amendment 2 (2007)
ISO 1000:1992, SI units and recommendation for the use of their multiples and of certain
other units
– 10 – 61020-1 © IEC:2009
2.2 Units and symbols
Units, graphic symbols, and letter symbols shall be, whenever possible, in accordance with

ISO 1000, IEC 60027 and IEC 60617.

Graphic symbols and letter symbols peculiar to a particular switch subfamily shall be defined

in the applicable detail specification. Graphic symbols and letter symbols peculiar to a group

of structurally similar switches shall be defined in the detail specification. When additional

units or symbols are required, they shall be derived in accordance with the principles of the
documents listed above whenever possible.

2.3 Terms and definitions
For the purposes of this document the terminology of IEC 60050-581 as well as the following
terms and definitions apply.
Terminology peculiar to a particular switch subfamily shall be defined in the applicable detail
specification. Terminology peculiar to a group of structurally similar switches shall be defined
in the detail specification.
The following terminology is common to all electromechanical switches. Where the definition
is compatible with an established IEC 60050 definition, the IEV number for the related
definition is given in brackets.
2.3.1
category temperature range
range of ambient temperature for which the switch has been designed to operate continuously
2.3.2
clearance
shortest distance in air between two conductive parts
2.3.3
contact bounce
intermittent and random opening of closed contacts and closing of open contacts which may
occur after contact transfer and which is caused by the switch mechanism
2.3.4
contact bounce time
time period measured from the moment of first closure of two mating contacts or first opening
of two closed contacts to the moment when all contact bounce ceases

2.3.5
contact disturbance
intermittent and random closing of open contacts and/or opening of closed contacts caused by
external influences such as shock and vibration
2.3.6
contact separation (gap)
distance between mating contacts when the contacts are open
2.3.7
contact set
group of contacts which all function in relation to the same pole of a switch
2.3.8
creepage distance
shortest distance along the surface of the insulation material between two conductive parts

61020-1 © IEC:2009 – 11 –
[IEV 151-15-50 modified]
2.3.9
double break switch
switch that opens a conductor at two points in series with each other

2.3.10
double throw
term applied to a contact arrangement to denote that each contact form included is a make-

break
2.3.11
duty cycle
ratio of conducting (ON) time to the total time for one cycle; for example, 30 % ON
2.3.12
electromechanical switch
switch which opens, closes, or changes the connection of an electrical circuit by the
mechanical motion of conducting parts (contacts)
2.3.13
lower category temperature
minimum ambient temperature for which a switch has been designed to operate continuously
2.3.14
pole of a switch
the part of the switch associated exclusively with one, electrically separated, conducting path
of the switch
NOTE 1 Those parts that provide a means for mounting and operating all poles together are excluded from the
definition of a pole.
NOTE 2 A switch is called "single-pole" if it has only one pole. If it has more than one pole, it may be called
"multi-pole" (two-pole, three-pole, etc.) provided that the poles are coupled in such a manner as to operate
together.
2.3.15
operating cycle
succession of operations from one position to another and back to the first position through all
other positions, if any
[IEV 441-16-02]
2.3.16
opposite polarity
two parts of a switch such that when connected together may result in operation of the line
fuses to the power supply
2.3.17
single throw
term applied to a contact arrangement to denote that each contact form included is a single
contact pair
2.3.18
snap-action
type of switching action in which the speed of the moving contact is relatively independent of
the speed of the actuating mechanism

– 12 – 61020-1 © IEC:2009
2.3.19
surface mounting switch
small-sized switch which is suitable for surface mounting on the printed wiring board,

consisting of terminals and framing parts

2.3.20
upper category temperature
maximum ambient temperature for which a switch has been designed to operate continuously

2.4 Preferred values
The detail specification may prescribe any preferred values for rated and limiting values,
characteristics, tolerances, requirements and dimensions applicable to the whole subfamily.
2.4.1 Clearance and creepage distances
The detail specification shall specify either the minimum clearance and creepage distances or
the minimum dielectric test voltage under specified air pressure for functional insulation. For
basic, supplementary or reinforced insulation the minimum clearance and creepage distances
shall be specified in accordance with Clause 20 of IEC 61058-1.
2.5 Marking
Where space permits after national or contractual marking requirements (for example, safety
requirements) have been satisfied, each switch shall be marked with the following information:
a) manufacturer's name or trademark;
b) identification number;
c) terminal identification when specified by the detail specification;
d) date code: the date code shall be in accordance with IEC 60062.
Other markings may be applied to the switches provided they do not obscure or confuse the
required markings. When conditions do not permit full marking on the switch, the markings
shall be applied in the order of preference shown above. Any required marking that cannot be
applied to the switch, shall be marked on the smallest packing unit of the switch.
3 Quality assessment procedures
NOTE See Annex A (informative) for guidelines on quality assurance procedures.
4 Test and measurement procedures

4.1 General
Any detail specification shall contain tables showing the tests to be conducted, the
measurements to be made before and after each test or group of tests, and the sequence in
which they shall be carried out. The measuring conditions shall be the same for initial and
final measurements. When tests are performed in a sequence, the final measurements of one
test may be taken as the initial measurements for the succeeding test.
If national specifications within any quality assessment system include test methods other
than those specified in the above documents, the test methods shall be fully described.
Not all the test methods prescribed herein are applicable to all types of switches. The detail
specification shall prescribe the test methods which are applicable for that type of switch.

61020-1 © IEC:2009 – 13 –
When necessary, additional test methods and/or details of the test methods shall be

prescribed by the detail specification.

4.1.1 Tolerances
Unless otherwise specified, the actual value of the parameters, for example test voltage, test

current, test force or test torque shall be within 5 % of the specified values of the switch.

4.1.2 Preconditioning
Unless specified by the test method, the switches shall not be subjected to any special
preparations, such as cleaning, prior to or during the tests.

4.1.3 Mounting
When mounting is prescribed by the test method, the switch shall be rigidly mounted by its
normal mounting means and connected as specified in the detail specification. The method of
mounting and the materials used for mounting shall not adversely affect the electrical or
mechanical performance of the switch.
4.2 Standard atmospheric conditions
The standard atmospheric conditions shall be in accordance with Clause 5 of IEC 60068-1.
4.3 General examination
4.3.1 Visual examination
4.3.1.1 Method
The visual examination shall be carried out by one of the following methods:
a) with the naked eye (normal strength of vision, normal colour perception, at the most
favourable viewing distance and with suitable illumination);
b) with magnifiers, if specified.
For the purpose of this standard, special methods, for example using polarized light (for
observing internal tensions in materials) or other indicators (for observing internal material
cracks or pores), are not permitted unless explicitly required by the detail specification.
4.3.1.2 Features
The following features shall be examined without magnification:

a) markings according to 2.5;
b) general appearance;
c) workmanship.
4.3.1.3 Requirement
The markings shall be correct and legible. The switch shall be manufactured in a careful and
workmanlike manner.
4.3.1.4 Details to be specified
When this test is required by the detail specification, the following details shall be specified:
a) details to be examined;
b) features to be checked;
– 14 – 61020-1 © IEC:2009
c) acceptability;
d) power of magnifier, if specified;

e) any deviation from the standard test method.

4.3.2 Dimensions
4.3.2.1 Method
The examination of dimensions shall be carried out with appropriate measuring equipment, for

example:
a) with a vernier gauge, a micrometer and a dial gauge;

b) with a measuring projector with a suitable linear magnification;
c) with a measuring microscope.
The following details shall apply.
a) The specified outline dimensions, detailed dimensions, clearances and creepage
distances shall be measured.
b) The accuracy and resolution of the measuring equipment (micrometers, callipers, visual
comparators, etc.) shall be commensurate with the dimensions being measured.
4.3.2.2 Requirement
The dimensions shall be within the limits specified by the detail specification.
4.3.2.3 Details to be specified
When this test is required by the detail specification, the following details shall be specified:
a) features to be checked;
b) gauging details, if applicable;
c) type and power of measuring equipment;
d) acceptability;
e) any deviation from the standard test method.
4.3.3 Dimensions, gauging
4.3.3.1 Method
The dimensions prescribed by the detail specifications as being suitable for gauging shall be
checked using the gauges or gauge dimensions specified by the detail specification.

4.3.3.2 Requirement
The switch shall comply with the prescribed gauging.
4.3.3.3 Details to be specified
When this test is required by the detail specification, the following details shall be specified:
a) features to be checked;
b) gauging details, if applicable;
c) type and power of measuring equipment;
d) acceptability;
e) any deviation from the standard test method.

61020-1 © IEC:2009 – 15 –
4.3.4 Mass
4.3.4.1 Method
The checking of mass should be carried out with appropriate measuring equipment, for
example, with a balance.
The following details shall apply.

a) The accuracy and resolution of the measuring equipment shall be commensurate with the

mass being measured.
b) The measurement shall include all removable parts (mounting hardware, etc.) prescribed

by the detail specification.
4.3.4.2 Requirement
The mass shall be within the limits specified by the detail specification.
4.3.4.3 Details to be specified
When this test is required by the detail specification, the following details shall be specified:
a) features to be checked;
b) gauging details, if applicable;
c) type and power of measuring equipment;
d) acceptability;
e) any deviation from the standard test method.
4.3.5 Functional operation
4.3.5.1 Object
The objective of the examination is the assessment of the proper functioning of all switching
operations.
4.3.5.2 Method
For coded switches, each switching circuit shall be connected to a monitoring circuit which
has a maximum current of 150 mA, and provides an indication of current flow. With the
exception of coded switches, the test facility may use the contact resistance test to check the
switching circuit.
The correct functioning of all mechanical detents, latching, locking, interlocking, and self-
return mechanisms shall be checked.
The correct functioning of all electrical non-switching operations, such as lamp circuits or
solenoids, shall be checked at their rated voltage and/or rated current.
4.3.5.3 Requirement
The functional operation of the switch, including the sequence of contact operations, shall
comply with the requirements specified by the detail specification.

– 16 – 61020-1 © IEC:2009
4.3.6 Operating characteristics

4.3.6.1 Operating force
4.3.6.1.1 Object
The objective of this test is to measure the force to move the actuating part of a switch from

any one position to the next.
4.3.6.1.2 Preparation of specimens

The specimens shall be prepared as specified by the detail specification.

The specimens shall be rigidly mounted on a metal plate using the fixing devices specified in
the detail specification. The metal plate shall be strong enough to withstand the forces
applied. The length and width of the metal plate shall be such that the contour of the
specimen is exceeded.
4.3.6.1.3 Method of measurement
The force shall be applied to the actuating part in the direction and at the point specified in
the detail specification. Unless otherwise specified, the force shall be applied until the
actuating part has travelled from a first stable equilibrium position to its next stable
equilibrium position or a stop, and the switch has operated electrically or the specified contact
resistance is achieved.” The maximum force necessary to move the actuating part to the next
stable position or stop shall be measured and recorded. In the case of a switch in which the
actuator does not take up a second stable equilibrium position (momentary position), the force
required to move the actuator to the operating position shall be measured and recorded.
If appropriate, the measurements of operating force shall be carried out in both directions. In
each direction, the number of measurements shall be as specified in the detail specification.
The method for measuring other mechanical operating characteristics shall be specified by
the detail specification. The method for measuring other operating characteristics such as
temperature, air pressure, etc. shall be specified by the detail specification.
4.3.6.1.4 Requirement
All measured values shall be within the limits specified in the detai
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