Measurement method for assessing the compatibility of induction hob and cookware

This document describes a method which determines the electrical parameters for compatibility of cookware and induction hobs for household use. Cookware is an integral part of the cooking system; electrical parameters can affect the cooking process regarding the required power setting, speed of heating up, sufficient power for different cooking processes etc.
For determining the compatibility of a cookware to an induction cooking zone and cooking area, a measurement device and a measurement procedure is specified in this deliverable. It allows measuring the resistivity and/or impedance of the cookware under test (CUT) in a repeatable and reproducible way. The measured electric properties indicate the compatibility characteristics of a cookware on an induction cooking zones and cooking area.
For determination the compatibility of an induction cooking zone or cooking area with a cookware, this document describes the measurement how to determine the power generated by the hob under test in combination with the selected cookware.
NOTE 1   For definitions of induction hob, induction cooking zone and cooking area EN 60350 2 is relevant.
Further performance characteristics of hobs which are of interest to the user, like energy consumption, heating up time or heat distribution are not addressed. This document does not deal with safety requirements.
NOTE 2   Further performance characteristics for hobs are covered in EN 60350 2.
NOTE 3   Further performance characteristics for cookware are covered in EN 12983 1 and EN 12983 2.
NOTE 4   This document does not deal with safety requirements (IEC 60335 2 6 and IEC 60335 2 9).
Appliances covered by this document may be built-in or portable induction hobs. The hob can also be a part of a cooking range.

Messmethode zur Bewertung der Kompatibilität von Induktionskochfeldern und Kochgeschirr

Méthode de mesure pour évaluer la compatibilité des tables de cuisson et des ustensiles de cuisine

Le présent document décrit une méthode qui permet de déterminer les paramètres électriques pour assurer la compatibilité des ustensiles de cuisine et des tables de cuisson destinés à un usage domestique. Les ustensiles de cuisine font partie intégrante du système de cuisson; les paramètres électriques peuvent avoir une incidence sur le processus de cuisson, notamment sur le réglage de puissance exigé, la vitesse de chauffage des aliments, la puissance suffisante pour les différents processus de cuisson, etc.
Dans ce contexte, le présent document spécifie un dispositif et une procédure de mesure afin de déterminer la compatibilité d'un ustensile de cuisine avec une zone de cuisson par induction et une surface de cuisson. Cette approche permet de mesurer la résistivité et/ou l'impédance de l'ustensile de cuisine en essai (CUT, Cookware Under Test) de manière répétable et reproductible. Les propriétés électriques ainsi mesurées reflètent les caractéristiques de compatibilité d'un ustensile de cuisine utilisé sur une zone de cuisson par induction et une surface de cuisson.
Pour évaluer la compatibilité d'une zone de cuisson par induction ou d'une surface de cuisson avec un ustensile de cuisine particulier, le présent document spécifie comment effectuer les mesurages afin de déterminer la puissance émise par la table de cuisson en essai, utilisée avec l'ustensile choisi.
NOTE 1   Pour les définitions des termes "table de cuisson", "zone de cuisson par induction" et "surface de cuisson", consulter l'EN 60350 2.
Le présent document ne traite pas des autres caractéristiques d'aptitude à la fonction qui intéressent l'utilisateur, comme la consommation d'énergie, le temps de montée en température ou la répartition de la chaleur. Le présent document ne traite pas des exigences de sécurité.
NOTE 2   Les autres caractéristiques d'aptitude à la fonction des tables de cuisson sont traitées dans l'EN 60350 2.
NOTE 3   Les autres caractéristiques d'aptitude à la fonction des ustensiles de cuisine sont traitées dans l'EN 12983 1 et l'EN 12983 2.
NOTE 4   Le présent document ne traite pas des exigences de sécurité (IEC 60335 2 6 et IEC 60335 2 9).
Les appareils couverts par le présent document peuvent être des tables de cuisson encastrées ou mobiles. La table de cuisson peut également être incorporée à une cuisinière.

Merilna metoda za oceno kompatibilnosti indukcijskih kuhališč in kuhinjske posode

General Information

Status
Published
Publication Date
13-Sep-2023
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
12-Sep-2023
Due Date
17-Nov-2023
Completion Date
14-Sep-2023

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SLOVENSKI STANDARD
SIST EN 50723:2023
01-november-2023
Merilna metoda za oceno kompatibilnosti indukcijskih kuhališč in kuhinjske
posode
Measurement method for assessing the compatibility of induction hob and cookware
Messmethode zur Bewertung der Kompatibilität von Induktionskochfeldern und
Kochgeschirr
Méthode de mesure pour évaluer la compatibilité des tables de cuisson et des ustensiles
de cuisine
Ta slovenski standard je istoveten z: EN 50723:2023
ICS:
97.040.20 Štedilniki, delovni pulti, Cooking ranges, working
pečice in podobni aparati tables, ovens and similar
appliances
SIST EN 50723:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50723:2023

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SIST EN 50723:2023


EUROPEAN STANDARD EN 50723

NORME EUROPÉENNE

EUROPÄISCHE NORM August 2023
ICS 97.040.20
English Version
Measurement method for assessing the compatibility of induction
hob and cookware
Méthode de mesure pour évaluer la compatibilité des tables Messmethode zur Bewertung der Kompatibilität von
de cuisson et des ustensiles de cuisine Induktionskochfeldern und Kochgeschirr
This European Standard was approved by CENELEC on 2023-07-24. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.



European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 50723:2023 E

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SIST EN 50723:2023
EN 50723:2023 (E)
Contents Page
European foreword . 3
Introduction . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 General conditions for the measurement . 6
4.1 Test room. 6
4.2 Electricity supply . 7
4.3 Instrumentation and measurements . 7
5 Dimensions. 8
5.1 Dimensions of a cooking zone . 8
5.2 Dimensions of cookware . 8
6 Specification of the measurement device for cookware . 8
6.1 Converter design . 8
6.2 Converter operation . 9
6.3 Induction coils . 9
6.4 Reference cookware .10
6.5 Glass ceramic and printing.10
7 Method for determining the compatibility of a cookware .11
7.1 Measuring of electrical properties .11
7.2 General procedure .13
7.3 Preparation of CUT .14
7.4 Measurements .14
7.4.1 Overview about the test cases .14
7.4.2 Test cases with reference power density – Test A and B .14
7.4.3 Test C - Case high power operation .21
7.4.4 Test D — Capability to control minimum non-pulsed power .24
8 Method for determining the compatibility of a hob .25
8.1 Purpose .25
8.2 Specification of the reference cookware with aluminium ring .25
8.3 Test procedure .27
8.3.1 Assigning the reference cookware with aluminium ring to a cooking zone .27
8.3.2 Measurement on a cooking zone starting in cold conditions .28
8.3.3 Measurement on a cooking zone starting in hot conditions .29
8.3.4 Assessment .30
Annex A (normative) Coil design .31
Annex B (normative) Converter design .35
Annex C (normative) Design of measurement device .37
Annex D (informative) Examples – test machine .39
Annex E (informative) Control loop of the measurement device .40
Bibliography .42
2

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SIST EN 50723:2023
EN 50723:2023 (E)
European foreword
This document EN 50723:2023 has been prepared by CLC/TC 59X “Performance of household and similar
electrical cooking appliances”.
The following dates are fixed:
• latest date by which this document has (dop) 2024-07-24
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2026-07-24
standards conflicting with this document
have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A complete
listing of these bodies can be found on the CENELEC website.
3

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SIST EN 50723:2023
EN 50723:2023 (E)
Introduction
To ensure that induction hobs designed by household industry and cookware designed by cookware
manufacturers are compatible a common platform for future innovations on both sides is needed. This document
provides measurements to assess the compatibility / interoperability within the system cooking.
Manufacturers of cookware and hobs can use the measurements to identify various properties of induction hobs
and cookware.
Standards application business, e.g. testing laboratories, can use this document for product test clearly to
identify the compatibility of cookware and induction hobs.
Finally, the consumer benefit is on the one hand a better-harmonized product range (cookware/hob) and on the
other hand, a clear product information regarding compatibility based on a standardized method.
4

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SIST EN 50723:2023
EN 50723:2023 (E)
1 Scope
This document describes a method which determines the electrical parameters for compatibility of cookware
and induction hobs for household use. Cookware is an integral part of the cooking system; electrical parameters
can affect the cooking process regarding the required power setting, speed of heating up, sufficient power for
different cooking processes etc.
For determining the compatibility of a cookware to an induction cooking zone and cooking area, a measurement
device and a measurement procedure is specified in this document. It allows measuring the resistivity and/or
impedance of the cookware under test (CUT) in a repeatable and reproducible way. The measured electric
properties indicate the compatibility characteristics of a cookware on an induction cooking zones and cooking
area.
For determination the compatibility of an induction cooking zone or cooking area with a cookware, this document
describes the measurement how to determine the power generated by the cooking zone under test (ZUT) in
combination with the selected cookware.
NOTE 1 For definitions of induction hob, induction cooking zone and cooking area EN 60350-2 is relevant.
Further performance characteristics of hobs which are of interest to the user, like energy consumption, heating
up time or heat distribution are not addressed. This document does not deal with safety requirements.
NOTE 2 Further performance characteristics for hobs are covered in EN 60350-2.
NOTE 3 Further performance characteristics for cookware are covered in EN 12983-1 and EN 12983-2.
NOTE 4 Safety requirements are covered in IEC 60335-2-6 and IEC 60335-2-9.
Appliances covered by this document can be built-in or portable induction hobs. The hob can also be a part of
a cooking range.
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.
EN ISO 80000-1:2022, Quantities and units  Part 1: General (ISO 80000-1:2022)
EN 60350-2:2018, Household electric cooking appliances  Part 2: Hobs  Methods for measuring
performance
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
compatibility
capability of an induction hob and a cookware to perform together adequately assessed by the measured
electrical parameters derived in the measurements
Note 1 to entry: The relevant electric parameters are defined in 3.2 to 3.7. This document describes the measurement of
these electrical parameters but does not provide limits.
5

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SIST EN 50723:2023
EN 50723:2023 (E)
3.2
resistivity
value obtained by measuring the up taken input power, divided by the square of rms current of the coil
3.3
active power
P
act
power supplied to the measuring device by the mains (average power during mains cycle)
3.4
target input power
P
req
requested power determined by the inner diameter of the cookware
3.5
reference frequency
working frequency at resonant power
3.6
peak current
I
peak
maximum current in each mains cycle
3.7
rms current
I
rms
root-mean-square of the current flowing in coil during a mains cycle
3.8
cookware under test
CUT
cookware sample undergoing examination
3.9
cooking zone under test
ZUT
cooking zone undergoing examination
3.10
boost position setting
marked control setting at maximum power, which is automatically limited in duration
Note 1 to entry: Marked setting on the appliance, which is described in the instructions for use.
3.11
maximum power
maximum possible power setting while only one cookware is used
Note 1 to entry: Boost position setting is not considered.
4 General conditions for the measurement
4.1 Test room
The tests are carried out in a substantially draught-free room in which the laboratory ambient temperature is
maintained at (23 ± 2) °C.
6

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SIST EN 50723:2023
EN 50723:2023 (E)
This ambient temperature is measured at a point that is at the same height as the hob positioned at working
height and at a distance of 0,5 m from one of the front edges of the appliance.
NOTE The working height is between 800 mm and 1 000 mm normally.
The measurement of the ambient temperature shall not be influenced by the appliance itself or by any other
appliance.
4.2 Electricity supply
The measurement device is supplied at rated voltage with a relative tolerance of ± 1 %.
The supply voltage shall be maintained at the main terminal at 230 V with a relative tolerance of ± 1 % while the
heating elements are switched on.
The supply voltage shall be essentially sinusoidal; the total harmonic distortion shall be less than 3 %.
If the induction hob has a rated voltage range, the tests are carried out at the nominal voltage of the country
where the appliance is intended to be used.
NOTE In case of a fixed cable, the plug (or the end of the cable) is the reference point to maintain the voltage.
The mains frequency shall be at the rated frequency 50 Hz with a relative tolerance of ± 1 % throughout the
test.
4.3 Instrumentation and measurements
Instruments used and measurements made for this document shall comply with the specifications in
Tables 1 and 2.
Table 1 — Instruments
Parameter Unit Minimum accuracy Additional requirements
resolution
dimensions mm 1 mm
time s 1 s ± 1 s
coil current A ± 0,5 % Current value is measured
within a bandwidth of at
least 5 MegaSamples and
filter bandwidth of 500 kHz.
voltage V ± 0,5 % Voltage value is measured
within a bandwidth of at
least 20 KiloSamples.
power W - ± 1 % Mains power value is
measured within a
bandwidth of at least 20
KiloSamples and filter
bandwidth of 2 kHz.
temperature of the °C ± 2 K
inductor coils
temperature of the water °C ± 1K
Energy consumption ZUT Wh ± 1 % Very quick electronic on/off
periods shall be taken into
account by measurement
techniques
7

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SIST EN 50723:2023
EN 50723:2023 (E)
Table 2 — Measurements
Parameter Unit accuracy
Voltage V ± 0,5 %
rms voltage V ± 0,5 %
rms
Current A ± 0,5 %
rms current A ± 0,5 %
rms
Power, average W ± 1 %
Energy consumption Wh Sampling rate < 1 s
measurement ZUT (digital measurement
data)
If numbers have to be rounded, they shall be rounded to the nearest number according to EN ISO 80000-
1:2022, B.3, Rule B. If the rounding takes place to the right of the comma, the omitted places shall not be filled
with zeros.
5 Dimensions
5.1 Dimensions of a cooking zone
The dimension of a cooking zone is determined by measuring the marked area on the surface. The
measurement procedure described in EN 60350-2 is applied. The dimension of a cooking zone is reported
rounded to mm.
5.2 Dimensions of cookware
For the purpose of this document the diameter of the inner bottom of the cookware is relevant. The inner bottom
diameter of a cookware corresponds to the usable surface of the inner base.
Follow the instruction of the cookware manufacturer regarding the inner bottom diameter of the cookware. If no
instructions are given, the inner diameter is measured with a flexible tape. For this the flexible tape is positioned
on the inner bottom surface, see Figure 1, searching the maximum measurable diameter.

Figure 1 — Inner bottom surface
6 Specification of the measurement device for cookware
6.1 Converter design
Half bridge series resonant converter with a maximum power of 3 700 W shall be used.
The reference frequency of the converter including the coil shall be (20 ± 2) kHz at maximum power, while the
reference cookware is fully covering the coil. The maximum power per coil shall be in accordance to Table 3.
The required converter design is given in Annex B.
8

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SIST EN 50723:2023
EN 50723:2023 (E)
The working frequency range shall be from 19 kHz to 45 kHz.
For the measurement device means for protection shall be provided to avoid exceeding a peak
current ≥ 100 A .
pk
An overview about the measurement device (see Figure C.2) and the measurement position (See Figure C.1)
is given in Annex C.
6.2 Converter operation
Induction coil current is controlled by frequency. The duty cycle is fixed 50 % (= symmetric control of high and
low switch). The converter shall limit the current for each coil size including frequency de-rating, limit is 45 A .
rms
NOTE Annex E gives the information on the control loop of the measurement device.
The glass temperature in the centre of the coils is measured and monitored. The glass temperature shall
be ≥ 70 °C during measurement, since the measurement shall not be done in cold conditions. Blowers are
needed in order to cool down coils and electronics.
6.3 Induction coils
Induction coils used for the measurement device shall satisfy the following requirements:
— diameter of test coils are defined by outer diameter of electrical winding;
— the winding has neutral design with constant gaps between the turns;
— continuous winding made from stranded copper wire, bar ferrites, no full ferritic coverage;
— number of turns and surface of the ferrites defined in Annex A;
— inner diameter for coil with the diameter of 160 mm shall be (25 ± 1) mm; for all the other inner diameter
shall be coils are of (45 ± 5) mm; see Figure 2;
— coils are placed on an aluminium carrier and spring loaded to the glass and this aluminium carrier shall be
earthed;
— distance between the upper surface of the windings of the inductors and the upper glass ceramic surface
shall be (6,5 ± 0,2) mm;
— minimum inductivity for coils placed on the aluminium carrier with a diameter ≤ 210 mm is 63 µH and for
coils with a diameter > 210 mm until ≤ 270 mm is 59 μH and for > 270 mm the minimum inductivity is
55 μH. (Conditions: measured at 10 kHz, 1 V and 20 °C, with no coverage);
— the maximum power of the coil shall be reached with the reference cookware with fitting diameter at a
reference frequency of (20 ± 2) kHz;
— PT100 sensor mounted in the centre of the coil for measuring the temperature of the bottom side of the
glass;
— electrical insulation layer shall be mounted above the induction coil.
9

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SIST EN 50723:2023
EN 50723:2023 (E)

Key
W is the inner diameter
D is the diameter of the coil
Figure 2 — Coil with inner diameter
The required coil design is given in Annex A.
In Table 3 the coil diameter and related maximum power is stated.
Table 3 — Coil diameter and related maximum power
2
coil diameter in mm power density in W/cm max power in W
160 10,7 2 148
180 10,7 2 718
210 10,7 3 700
240 8,2 3 700
270 6,5 3 700
300 5,2 3 700
6.4 Reference cookware
For the purposes of this document, the specification for the standardized cookware given in EN 60350-2 applies.
6.5 Glass ceramic and printing
The maximum glass temperature – measured below – shall be up to 240 °C. For the test procedure, the
maximum glass temperature shall be limited by software to maximum 160 °C (to avoid empty pot boiling).
Each cooking zone shall be printed on the glass ceramic as follows:
— printed circle with the same diameter as the coil;
10

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SIST EN 50723:2023
EN 50723:2023 (E)
— marked circles in 10 mm steps up to diameter equal to the nominal coil diameter + 20 mm (see Figure 3).

Figure 3 — Marked circle with the same diameter as the coil (thick line) and smaller and larger circles
in 10 mm steps
NOTE An example for a printing is shown in Annex D.
7 Method for determining the compatibility of a cookware
7.1 Measuring of electrical properties
The test procedures of this document allow determining electrical properties of cookware on typical domestic
induction hobs. The physical effect of coupling between induction coil and cookware is similar on typical
domestic induction hobs, but the scaling of the determined values varies from technology to technology
according to their individual design, e.g. number of turns and ferrite bars of the inductor coil, distance coil to
cookware.
The Cookware Under Test (CUT) is operated for the tests described in 7.4 in a clearly defined operating point
and compared to the reference cookware operated at the same operating point, e.g. at the same active power
or at the same operating frequency.
The CUT is relatively compared to the reference cookware with similar or slightly smaller diameter and the delta
between CUT and reference is the measurement result.
The following values are measured for each test described in 7.4:
— U mains input voltage behind shunt and before rectifier;
AC
— I mains current through shunt;
AC
— I high frequency current through induction coil;
HF
— f operating frequency of half bridge converter (frequency of coil current).
op
One measurement cycle takes 20 ms, which is related to a complete mains sine period of 50 Hz. Therefore,
nonlinear properties of cookware in different operating points during a half wave of the mains voltage are
included.
11

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SIST EN 50723:2023
EN 50723:2023 (E)
The input voltage U is calculated as the difference between absolute value of U and the voltage drop
DC AC
on the rectifier. I is equal to the absolute value of I .
DC AC
P I
The active power and the rms value of coil current is calculated for a complete measurement cycle
act coil
according to Formulae (1) and (2).
T
1
P = U I dt (1)
act DC DC

0
T
T
1
2
I = I dt (2)
coil HF

0
T
Where:
is the active power drawn from mains averaged along the period T;
P
act

T is the averaging period (for 50 Hz is T = 20 ms);
is the mains voltage U UU− - mains voltage minus the shunt resistor and
U
DC AC rectifier
DC
rectifier voltage drop;
I is the absolute value of ;
I
DC
AC
is the coil rms current calculated along the averaging period T;
I
coil
is the operating frequency of the half bridge converter (coil current frequency).
f
op
The electrical equivalent values resistivity R is calculated according to Formula (3):
P
act
R=
(3)
2
I
coil
The inductivity of the coil with the coupled cookware is calculated assuming that the measured coil current I
coil
has no harmonic content; it contains only the first harmonic. This assumption is made based on the fact that the
inverter is a half bridge series resonant, therefore the harmonics beyond the first one are quite filtered. The error
introduced proceeding this way is < 2 %.
The inductivity is calculated according to Formulae (4) to (7):
2
11
2
L ()ZR−+ (4)
1 11
ωωc
r
Where:
st
is the 1 harmonic complex impedance of the resonant tank;
Z
1
1
ZR=+ ()Lω− j (5)
11 1

r
12
=
=

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SIST EN 50723:2023
EN 50723:2023 (E)
U
1
Z = (6)
1
t
coil
U
41
m
U = (7)
1
π 2
2
Where
st
is the 1 harmonic resistance;
R
1
st
is the 1 harmonic inductance;
L
1
is the resonant capacitor;
C
r
ω
is the angular frequency ωπ= 2 f ;
op
is the actual power drawn from the mains;
P
act
is the required power for each test (depends on the inner pot diameter);
P
req
is the rms current measured in the coil. It is approximately equal to the first harmonic of the coil
I
coil
current;
st
is the half bridge 1 harmonic output voltage (square wave). Averaged along a mains cycle.
U
1
The working frequency is stated.
Additionally, the resistivity is determined at each switching period during a half mains cycle where the current
varies from 0 to maximum current. The relationship between current and resistivity is obtained in order to assess
the saturation effects.
7.2 General procedure
— pre-calibration of machine: Input shall be inner bottom cookware diameter; = > P is set automatically.
req
Current for reference cookware at P is known by calibration;
req
— deliver target power P depending on inner bottom diameter of cookware sample;
req
— check that no protection - over currents, temperature limits or resonant voltage – is active and affecting the
test result;
— measure the coil current;
— calculate P and I for complete sine wave 20 ms;
act coil
— calculate:
P
act
R= (8)
2
I
coil
13

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SIST EN 50723:2023
EN 50723:2023 (E)
— comparison of I (or R) of the cookware sample with reference cookware with similar inner bottom
coil
diameter and next smaller diameter;
— calculate inductivity based on first harmonic approach calculation.
7.3 Preparation of CUT
The inner bottom diameter of the CUT is determined according to 5.2.
The CUT is filled with potable water with a temperature of (20 ± 5) °C up to a filling height of (25 ± 5) mm.
It is not necessary to place a lid.
7.4 Measurements
7.4.1 Overview about the test cases
All test cases are performed on inductor coil sizes related to the diameter of the CUT.
The general approach for the different cookware sizes is stated in Table 4.
Table 4 — Overview on test cases
Inner cookware Fitting Small coil Medium Large XL coil XXL coil XXXL
diameter d in mm coil 160 mm coil coil 240 mm 270 mm coil
diameter 180 mm 210 mm 300 mm
in mm
120 < d ≤ 160 160 A/C/D  B
160 < d ≤ 190 180  A/C/D  B
190 < d ≤ 220 210   A/C/D  B
220 < d ≤ 250 240    A/C/D  B
250 < d ≤ 280 270     A/C/D B
280 < d ≤ 300 300      A/C/D
NOTE A, B, D and C is related to the test cases defined in 7.4.
Tests A, C and D are performed on a fitting coil diameter and may be performed in one continuous procedure.
2
First test A with 5,5 W/cm is performed as soon as the water is boiling, then switch to Pmax for test C, finally
test D (40 kHz) is performed.
7.4.2 Test cases with reference power density – Test A and B
7.4.2.1 Target input power
The target input power for reference power density, which is related to the inner diameter of the cookware, is
2
stated in Table 5. The reference power density for compatibility testing is 5,5 W/cm up to 210 mm inner bottom
diameter of the cookware. The power density is derated for larger cookware diameters as defined in Table 5.
14

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SIST EN 50723:2023
EN 50723:2023 (E)
Table 5 — Inner cookware diameter and related target power for Tests A and B (example)
Area
Reference power
Inner
cookware Target input power
density
cookware
bottom
P in W
req
2
diameter in cm
in W/cm (P /A)
req
2
A in cm
12 113 5,5 622
13 133 5,5 730
14 154 5,5 847
15 177 5,5 972
16 201 5,5 1 106
17 227 5,5 1 248
18 254 5,5 1 400
19 284 5,5 1 559
20 314 5,5 1 728
21 346 5,5 1 905
22 380 5,25 1 995
23 415 5,05 2 097
24 452 4,81 2 174
25 491 4,55 2 235
26 531 4,29 2 278
27 573 4,02 2 301
28 616 3,74 2 300
> 28   2 300
The numbers in Table 5 are calculated following these principles:
2
— power density is 5,5 W/cm for a cookware with an inner di
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