kSIST FprEN IEC 63203-401-1:2026

• Status: Not Published
• Public Enquiry End Date: 26-Feb-2026
• ICS: 31.020 - Electronic components in general
• Technical Committee: I09 - Imaginarni 09
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 28-Oct-2026
• Due Date: 16-Dec-2026
• Ref Project: FprEN IEC 63203-401-1:2026 - Wearable electronic devices and technologies - Part 401-1: Devices and systems: functional elements - Measurement method of the stretchable resistive strain sensor

• Revises: SIST EN IEC 63203-401-1:2024 - Wearable electronic devices and technologies - Part 401-1: Devices and systems - functional elements - Evaluation method of the stretchable resistive strain sensor (IEC 63203-401-1:2023)
• Effective Date: 12-Dec-2023

kSIST FprEN IEC 63203-401-1:2026 is a Slovene standard published by SIST for wearable electronic devices and technologies. It specifies a measurement method for stretchable resistive strain sensors, including how to determine the linear area, strain limits and gauge factor for large-deformation sensors. It is aimed at engineers, test laboratories, suppliers and buyers that need a common way to evaluate these sensor devices.

What does kSIST FprEN IEC 63203-401-1:2026 specify?

kSIST FprEN IEC 63203-401-1:2026 specifies how to measure the linear area and strain limits of stretchable resistive strain sensors, and how to determine their gauge factor. The standard is written for sensors that use resistance changes in conductive films made of conductive particles or organic elastic polymers.

The scope is deliberately narrow. It is not a measurement method for sensor materials, and it does not apply to conventional strain gauges based on thin metal films.

The document is organized into clauses on scope, normative references, terms and definitions, test environments, test specimens, test equipment, test procedure and report. The bibliography points to related terminology and older strain-gage test methods.

What are the key requirements of kSIST FprEN IEC 63203-401-1:2026?

• Clause 4 sets the test atmosphere. Tests are performed at 23 °C ± 2 °C and 50 % ± 10 % relative humidity, in line with ISO 291 class 2. In practice, this means results should be taken under controlled conditioning, so the sensor is not tested in an arbitrary room environment.

• Clause 5 requires a usable sensor device. The strain sensor must have at least a measurement terminal or lead wire for detecting resistance change, and an externally observable marking for gauge length. This matters because the method is aimed at sensor devices that can be measured and identified consistently, whether they are standalone parts or integrated onto a substrate.

• Clause 6.1 requires tensile loading and resistance measurement during stretching. A tensile testing machine is used to apply longitudinal deformation, and the sensor output is measured at the same time. Horizontal or vertical machines may be used, but the machine must support the intended deformation range without taking the sensor beyond its limit.

• Clause 6.2 allows either 2-terminal or 4-terminal resistance measurement. A 4-terminal method is recommended when the resistance is below 1 kΩ, and data recording is needed if response characteristics are being measured. In practice, this affects the accuracy of resistance readings and whether time-resolved behavior can be documented.

• Clause 6.3 calls for non-invasive length measurement. A quality-certified ruler or mechanical extensometer is used unless another method is agreed, and optical methods such as laser, interference light, camera systems or digital image correlation systems may be used when higher accuracy is needed. This helps the reader choose a method that tracks gauge-length change without altering the sensor.

• Clause 7 defines the evaluation flow. The tensile test produces a stress-strain curve and a strain-resistance curve, and these are used to find the mechanical linear region, electrical linear region, their limits and the gauge factor. This is the core of the standard, because it turns raw test data into the sensor performance values that users compare.

• Clause 7.2 uses a 1.0 % error criterion for linearity. The straight-line region is identified by comparing the measurement curve with the line from the origin, and the strain value at which the error reaches 1.0 % becomes the mechanical or electrical strain limit. The narrower linear region defines the sensor’s linear area, and the smaller limit defines the strain limit.

• Clause 7.3 warns about response, creep and hysteresis. These effects are treated as error-like behavior, and later tests such as response characteristics should be performed at 50 % or less of the strain limit. In practice, this gives a conservative operating range for repeatable testing.

What terms does kSIST FprEN IEC 63203-401-1:2026 define?

• Gauge factor (G_F) - the ratio of resistance change to original resistance, divided by engineering strain along the stretching axis, used to describe sensor sensitivity.
• Gauge length - the length of the strain-sensing area in the direction of the measurement axis, which sets the active sensing span.
• Mechanical linear region - the part of the stress-strain relationship that is treated as linear within the stated error criterion, and which marks the mechanically effective measurement area.
• Electrical linear region - the part of the strain-resistance relationship that is treated as linear within the stated error criterion, and which marks the electrically effective measurement area.
• Strain limit - the smaller of the mechanical strain limit and the electrical strain limit, beyond which continued sensor operation is not guaranteed.

Who uses kSIST FprEN IEC 63203-401-1:2026?

kSIST FprEN IEC 63203-401-1:2026 is used by developers and evaluators of wearable electronic devices and technologies, especially where strain sensors are built into flexible structures. It is relevant for sensor designers, test laboratories, manufacturers, and quality or procurement teams that need to compare sensor devices by the same measurement method.

It is also useful when a strain sensor is either a standalone device or integrated into the object being measured. That makes it practical for product qualification, incoming inspection, supplier comparison and test reporting.

What changed in kSIST FprEN IEC 63203-401-1:2026 from the previous edition?

The document says that ED1 had unresolved technical issues, including confusion between evaluation of sensor devices and evaluation of sensor materials. In ED2, the test method was fundamentally reviewed and revised as a measurement method for sensor devices.

Which standards are used with kSIST FprEN IEC 63203-401-1:2026?

• ISO 291:2008 - the normative reference used for the standard atmosphere in clause 4.
• IEC 63203-101-1:2021 - listed in the bibliography for terminology related to wearable electronic devices and technologies.
• ASTM E251-92 - listed in the bibliography as a related method for performance characteristics of metallic bonded resistance strain gages.

What does the kSIST FprEN IEC 63203-401-1:2026 document contain?

The document includes two example figures showing strain sensor constructions, with labeled parts such as substrate, sensing material, electrode, lead wire, sensing area and gauge length. It also gives the test equipment needed for tensile loading, resistance measurement and non-invasive length measurement.

Clause 7 sets out the test procedure, including the stress-strain curve, the strain-resistance curve, the linearity criterion and the gauge factor calculation. Clause 7.3 discusses response, creep and hysteresis as practical behavior to consider during testing.

Clause 8 lists the report items to be recorded: sensor ID, test environment, mechanical linear region and strain limit, electrical linear region and strain limit, overall linear range and strain limit, and gauge factor.

SLOVENSKI STANDARD
oSIST prEN IEC 63203-401-1:2026
01-februar-2026
Nosljive elektronske naprave in tehnologije - 401-1. del: Naprave in sistemi:
Funkcionalni elementi - Merilna metoda raztegljivega uporovnega senzorja
napetosti
Wearable electronic devices and technologies - Part 401-1: Devices and systems:
Functional elements - Measurement method of the stretchable resistive strain sensor
Technologies et dispositifs électroniques prêt-à-porter - Partie 401-1: Dispositifs et
systèmes: éléments de fonctionnement - Méthode de mesure du capteur de déformation
extensible de type résistif
Ta slovenski standard je istoveten z: prEN IEC 63203-401-1:2025
ICS:
31.020 Elektronske komponente na Electronic components in
splošno general
oSIST prEN IEC 63203-401-1:2026 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN IEC 63203-401-1:2026

oSIST prEN IEC 63203-401-1:2026
124/359/CDV
COMMITTEE DRAFT FOR VOTE (CDV)

PROJECT NUMBER:
IEC 63203-401-1 ED2
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2025-12-05 2026-02-27
SUPERSEDES DOCUMENTS:
124/336/CD, 124/352/CC
IEC TC 124 : WEARABLE ELECTRONIC DEVICES AND TECHNOLOGIES
SECRETARIAT: SECRETARY:
Korea, Republic of Mr Jae Yeong Park
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):
SC 47F
ASPECTS CONCERNED:
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
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for Vote (CDV) is submitted for parallel voting.
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This document is still under study and subject to change. It should not be used for reference purposes.
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Countries” clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is
the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Wearable electronic devices and technologies - Part 401-1: Devices and systems: functional
elements - Measurement method of the stretchable resistive strain sensor

PROPOSED STABILITY DATE: 2031
NOTE FROM TC/SC OFFICERS:
download this electronic file, to make a copy and to print out the content for the sole purpose of preparing National
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oSIST prEN IEC 63203-401-1:2026
IEC CD 63203-401-1 ED2 © IEC 2025
1 CONTENTS
3 FOREWORD . 2
4 1 Scope . 5
5 2 Normative references . 5
6 3 Terms and definitions . 5
7 4 Test environments . 6
8 5 Test specimen . 6
9 5.1 Principle and precaution . 6
10 5.2 Sensor device to be measured . 6
11 6 Test equipment . 7
12 6.1 Tensile testing machine . 7
13 6.2 Resistance measurement device . 8
14 6.3 Length measurement means . 8
15 7 Test procedure . 8
16 7.1 Outline . 8
17 7.2 Linear region, strain limit, gauge factor . 9
18 7.2.1 Tensile test . 9
19 7.2.2 Mechanical linear region and mechanical strain limit . 9
20 7.2.3 Electrical linear region and mechanical strain limit . 9
21 7.2.4 Linear area and strain limit of strain sensor . 9
22 7.2.5 Gauge factor . 9
23 7.3 Error (informative) . 9
24 8 Report . 10
25 Bibliography . 11
oSIST prEN IEC 63203-401-1:2026
IEC CD 63203-401-1 ED2 © IEC 2025
28 INTERNATIONAL ELECTROTECHNICAL COMMISSION
29 ____________
31 WEARABLE ELECTRONIC DEVICES AND TECHNOLOGIES –
33 Part 401-1: Devices and systems: functional elements –
34 Measurement method of the stretchable resistive strain sensor
36 FOREWORD
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69 IEC 63203-401-1 has been prepared by IEC technical committee 124: Wearable electronic
70 devices and technologies. It is an International Standard.
71 The text of this International Standard is based on the following documents:
Draft Report on voting
124/223/FDIS 124/239/RVD
73 Full information on the voting for its approval can be found in the report on voting indicated in
74 the above table.
75 The language used for the development of this International Standard is English.
oSIST prEN IEC 63203-401-1:2026
IEC CD 63203-401-1 ED2 © IEC 2025
76 This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
77 accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
78 at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
79 described in greater detail at www.iec.ch/publications.
80 A list of all parts in the IEC 63203 series, published under the general title Wearable electronic
81 devices and technologies, can be found on the IEC website.
82 The committee has decided that the contents of this document will remain unchanged until the
83 stability date indicated on the IEC website under webstore.iec.ch in the data related to the
84 specific document. At this date, the document will be
85 • reconfirmed,
86 • withdrawn, or
87 • revised.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates
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oSIST prEN IEC 63203-401-1:2026
IEC CD 63203-401-1 ED2 © IEC 2025
91 Introduction
92 Generally, strain sensors (strain gauges) utilize changes in the electrical resistance of a thin
93 copper-nickel alloy coating formed on a polymer film such as PET film. The strain sensor is
94 bonded to the object to be measured, and the strain in the strain sensor caused by the strain in
95 the object to be measured is detected as a change in resistance of the thin metal film.
96 As is obvious from the sensor’s material and structure, the object to be measured is mainly a
97 high elastic modulus member such as a metal material, the amount of strain detected is very
98 small, and the resistance change that is the output is also small. Therefore, it is common to
99 detect resistance changes as voltage changes using a Wheatstone bridge circuit, without
100 directly measuring resistance values. In the range where the relationship between strain change
101 and resistance value change is linear, the proportionality constant between the two is called
102 the gauge factor. Several existing standards are known for gauge factor measurement and are
103 listed in Bibliography.
104 On the other hand, the strain sensor covered by this standard utilizes the change in resistance
105 caused by the deformation of a conductive material in which conductive filler is dispersed in a
106 stretchable polymer material (such as an elastomer).
107 However, compared to the strain sensor using thin metal film described above, the target strain
108 range and resistance value change range are significantly different, so new testing methods for
109 this type of strain sensor are needed. ED1 of this standard was published with unresolved
110 technical issues such as the confusion between evaluation of sensor devices and evaluation of
111 sensor materials.
112 In ED2, the test method has been fundamentally reviewed and revised as a measurement
113 method for sensor devices.
oSIST prEN IEC 63203-401-1:2026
IEC CD 63203-401-1 ED2 © IEC 2025
116 WEARABLE ELECTRONIC DEVICES AND TECHNOLOGIES –
118 Part 401-1: Devices and systems: functional elements –
119 Measurement method of the stretchable resistive strain
...