IEC 63172:2020

IEC 63172 ®
Edition 1.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical accessories –
Methodology for determining the energy efficiency class of electrical
accessories
Petit appareillage –
Méthodologie pour déterminer la classe d'efficacité énergétique du petit
appareillage
IEC 63172 :2020-03(en-fr)
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IEC 63172 ®
Edition 1.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical accessories –
Methodology for determining the energy efficiency class of electrical

accessories
Petit appareillage –
Méthodologie pour déterminer la classe d'efficacité énergétique du petit

appareillage
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.015; 29.120.01 ISBN 978-2-8322-8005-8

– 2 – IEC 63172:2020 © IEC 2020
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Description of the methodology . 8
4.1 General . 8
4.2 Relationship between accessories, their modes and energy efficiency class
relevance . 8
4.3 Functions embedded in electrical accessories. 9
5 Energy efficiency classes . 12
Annex A (informative) Measuring methods . 15
A.1 Measuring method – General . 15
A.2 Dimmers . 15
A.2.1 Three-wire dimmer (see Figure A.1) . 15
A.2.2 Two-wire dimmer (see Figure A.2) . 15
A.2.3 Three-wire dimmer with mechanical switch load side (see Figure A.3) . 16
A.2.4 Two-wire dimmer with mechanical switch load side (see Figure A.4) . 16
A.3 Presence movement detector . 16
A.3.1 Two-wire presence detector (see Figure A.5) . 16
A.3.2 Three-wire presence detector (see Figure A.6) . 17
A.4 HBES/BACS . 17
A.4.1 HBES/BACS control device (see Figure A.7) . 17
A.4.2 HBES/BACS power supply (see Figure A.8) . 17
A.5 Socket-outlet with further function (see Figure A.9) . 18
A.6 Electronic switch relays . 18
A.6.1 Two-wire electronic switch relay (see Figure A.10) . 18
A.6.2 Three-wire electronic switch relay (see Figure A.11) . 18
Bibliography . 19

Figure 1 – Levels of efficiency . 12
Figure A.1 Three-wire dimmer measuring method . 15
Figure A.2 Two-wire dimmer measuring method . 15
Figure A.3 – Three-wire dimmer with mechanical switch measuring method . 16
Figure A.4 – Two-wire dimmer with mechanical switch load side measuring method . 16
Figure A.6 – Three-wire presence detector measuring method . 17
Figure A.7 – HBES/BACS control device measuring method . 17
Figure A.8 – HBES/BACS power supply measuring method . 17
Figure A.9 – Socket-outlet with further function measuring method . 18
Figure A.10 – Two-wire electronic switch relay measuring method . 18
Figure A.11 – Three-wire electronic switch relay measuring method . 18

Table 1 – Relationship between accessories, their modes and energy efficiency class
(examples) . 9
Table 2 – Examples of functions in electrical accessories . 10

Table 3 – Energy efficiency classes . 12
Table 4 – Example of each function and the estimated time of usage for a dimmer . 13
Table 5 – Energy efficiency points . 14

– 4 – IEC 63172:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL ACCESSORIES –
Methodology for determining the energy efficiency class of electrical
accessories
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
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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 63172 has been prepared by IEC technical committee 23: Electrical
accessories.
The text of this International Standard is based on the following documents:
CDV Report on voting
23/830/CDV 23/863/RVC
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

– 6 – IEC 63172:2020 © IEC 2020
INTRODUCTION
The electric energy efficiency of homes and buildings is continuously increasing by reducing
the electric energy consumption of products. For example, changing from traditional
incandescent lighting to LED lighting.
Specific electrical systems and accessories, for example home and building electronic systems
(HBES) / building automation control systems (BACS), individual sensors, actors, actuators,
dimmers and load shedding equipment (LSE), can contribute to additional energy savings.
Additional savings can also be achieved by managing and monitoring electrical energy use,
depending on time, occupancy, inputs and needs from the grid.
HBES/BACS contribute to greater energy savings than the energy they consume to perform this
task. However, as every watt counts, it is necessary to optimize their own energy consumption
for given functionalities.
In the case of devices with more functionality (e.g. multi-channel switch actuators, control boxes,
etc.), this document provides a methodology for determining the energy efficiency class of
accessories based on the consumption of each function and their percentage of use. It aims to
enable the system designer to determine the most efficient system considering the increasing
user demand for additional functionalities.

ELECTRICAL ACCESSORIES –
Methodology for determining the energy efficiency class of electrical
accessories
1 Scope
This document provides a methodology for determining the energy efficiency class of electrical
accessories, to enable the system designer to determine the most efficient components for an
electrical installation, also considering all functionalities.
NOTE Functionalities are for example: wireless communication, network connectivity, timer, energy monitoring.
This methodology is based on the energy consumption, taking into account the individual
functions of the accessory.
The energy efficiency class approach contributes to the overall reduction of the energy
consumption of an electrical installation.
2 Normative references
There are no normative references in this document.
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:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
OFF mode
mode of the accessory having a direct control where the relevant electric load is deactivated
and is able to be activated by deliberate action on the accessory by the user
Note 1 to entry: In this mode, the accessory consumes no energy.
3.2
standby mode
mode of the accessory having a direct control where the relevant electric load is deactivated
and is able to be activated by deliberate action to the accessory by the user or the system
Note 1 to entry: In this mode, the accessory consumes energy to perform this function.
Note 2 to entry: This mode includes an interaction through displays regardless of the state of the electric load.
3.3
ON mode
mode of the accessory having a direct control where its electric load is activated and is able to
be deactivated by deliberate action to the accessory by the user or the system
Note 1 to entry: In this mode, the accessory consumes energy.
Note 2 to entry: In this mode, the consumed energy can be greater than the energy consumption in the standby
mode.
– 8 – IEC 63172:2020 © IEC 2020
3.4
control mode
mode of the electronic accessory not having direct control of connected loads, performing their
functions in such a way that a control signal can be internally generated or an external control
signal can be received, by wire or wireless, and processed leading to a change in the load
status
3.5
direct control
case where the current to the load flows through the accessory
3.6
standby energy consumption
energy consumed by an accessory in standby mode
3.7
operational energy consumption
energy consumed by an accessory in ON mode
3.8
control energy consumption
energy consumed by an accessory in control mode
3.9
energy efficiency (EE) class
numerical value assigned to an electrical accessory according to its energy performance
4 Description of the methodology
4.1 General
The method consists of different steps in order to obtain an energy efficiency class for a device.
This method takes the different functions and their different energy consumptions into account
as well as the different usage of the functions.
1) Identify the different functions of a device;
2) Measure the energy consumption of the different functions in their different operational
modes;
3) Take into account the different durations of usage of the different operational modes to get
a power consumption which considers the operational profile of the different functions;
4) Determine the associated energy efficiency points for every function;
5) Rescale the energy efficiency points according to the energy consumption for the different
functions related to the energy consumption of the whole device;
6) Sum up the rescaled energy efficiency points to get the energy efficiency points for the
whole device;
7) Determine the energy efficiency class using the energy efficiency points of the whole device.
This method allows for the extension of the energy efficiency tables according to technical
developments without the need for rescaling.
4.2 Relationship between accessories, their modes and energy efficiency class
relevance
Table 1 shows examples of accessories and energy efficiency class relevance according to
mode and type.
Table 1 – Relationship between accessories, their modes and
energy efficiency class (examples)
Accessory Direct OFF mode Standby Control ON Energy
control mode mode mode efficiency
class
relevance
2)
Mechanical switch Yes Yes N/A No Yes
No
2)
Mechanical switch with indicator Yes N/A Yes No Yes
No
light (indicator parallel to switch)
2)
Mechanical switch with indicator Yes Yes N/A No Yes
No
light
(indicator parallel to load)
2)
Socket outlet Yes Yes, N/A No Yes,
No
plug not plug
inserted inserted
Socket outlet with further function Yes N/A Yes No Yes, Yes
plug
inserted
Electronic switch relays Yes No Yes No Yes Yes
(2 wires or 3 wires)
Dimmers Yes No Yes No Yes Yes
(2 wires or 3 wires)
Three-wire dimmer with Yes No Yes No Yes Yes
mechanical switch (load side)
2)
Two-wire dimmer with mechanical Yes Yes N/A No Yes
No
switch (load side)
2)
Presence/Movement detector Yes No N/A Yes Yes
No
1) 1)
No No
Presence/Movement detector
Yes Yes Yes No Yes Yes
where the operation can be
selected also by mechanical
switch
Presence/Movement detector Yes No Yes No Yes Yes
forced with position by electronic
switch
Home and building electronic Yes N/A Yes Yes Yes Yes
1) 1)
systems (HBES) switches and
No No
building automations and control
system (BACS) switches
Load shedding equipment (LSE) Yes N/A Yes No Yes Yes
1)
Depending on the design.
2)
Owing to the fact that these devices have no other functions, they shall not be considered for the methodology
of this document as they cannot contribute to increase the energy efficiency within a system.

4.3 Functions embedded in electrical accessories
Modern accessories have been developed incorporating greater functionality to satisfy user
demands (e.g. for comfort and management function), such as remote access, monitoring,
automatic and easily programmable functions, network connectivity for interaction with home
and building electronic systems (HBES), building automation and control systems (BACS),
touch-free operation, for example in hospitals (see Table 2).
Even if more functionalities of the electrical accessories need additional energy, these functions
are essential to reduce the consumption of a building via, for example, HBES or BACS controls.
For example, remote functions of control applications allow the user to switch off loads without
being present.
– 10 – IEC 63172:2020 © IEC 2020
In order to determine the electric energy efficiency class of an accessory it is necessary to
analyse the energy consumption of embedded functionalities.
Since energy consumption also depends on the duration of usage of the various functions of
the accessory, the general approach of this document takes only the power into account. It
cannot also take into account the installation and use of these accessories.
For this approach, these functions need to be separately measured or separately calculated
based on the manufactures' data, see Annex A.
The energy efficiency (EE) classes determined by classification of the individual functions of an
electrical accessory are given in Clause 5.
An example of functions is given in Table 2.
Table 2 – Examples of functions in electrical accessories
Accessory Function
Mechanical switch Switching
Mechanical switch with indicator light (indicator Switching
parallel to switch)
Indicator (lamp)
Mechanical switch with indicator light (indicator Switching
parallel to load)
Indicator (lamp)
Socket outlet Outlet
Connection to provide power
Network connectivity
RF communication
Timer
Energy monitoring
Switching (relays)
Sensing (temperature, water, light, etc.)
Electronic switch Switching
(2 wires or 3 wires)
Display
RF communication
Network connectivity
Timer
Energy monitoring
Control inputs, e.g. 1 V to 10 V
Sensing (temperature, water, light, etc.)
Dimmers Dimming
(2 wires or 3 wires) Touch
RF communication
Power line communication
Wired communication
Network connectivity
Sensing (temperature, water, light, etc.)
Measuring (current, etc.)
Dimmers (2 wires or 3 wires) with mechanical Dimming
switch (load side)
Measuring (current, etc.)
Accessory Function
Presence and/or movement detector Presence/movement (passive infrared)
Presence/movement (radar)
Switching
Sensing (temperature, water, light, etc.)
RF communication
Wired communication
Network connectivity
Measuring (current, etc.)
Power line communication
Pre-heating (for cold outdoor area)
HBES/BACS control device Display
Dimming
Switching
Touch
RF communication
Power line communication
Wired communication
Network connectivity
Sensing (temperature, water, light, etc.)
Measuring (current, etc.)
LSE Switching
Display
Sensing
RF communication
Power line communication
Wired communication
Network connectivity
Measuring (current, etc.)
External accessories shall be dealt with separately.

– 12 – IEC 63172:2020 © IEC 2020
5 Energy efficiency classes
Figure 1 – Levels of efficiency
The energy efficiency of an electrical accessory is rated by classification into one of the

following energy efficiency classes (EE) (see Figure 1):
– EE X: accessory with no evaluation of energy efficiency (e.g. mechanical switch) not
considered for the methodology of this document, or accessory within the intended
scope of this document with no defined functional categorisation or energy point
allocation;
– EE 0: accessory with low energy efficiency;
– EE 1: accessory with medium energy efficiency;
– EE 2: accessory with high energy efficiency.
Table 3 – Energy efficiency classes
Energy efficiency points Energy efficiency class
No evaluation EE X
Above 0 up to and including 6 energy efficiency points EE 0
Above 6 up to and including 8 energy efficiency points EE 1
Above 8 energy efficiency points EE 2
NOTE Energy efficiency classes can be extended in future due to new technologies or
improvements.
The following procedure is proposed as a basis for the energy efficiency classification:
a) the power consumption for each function and its estimated time of use shall be identified;
b) depending on the power consumption, for each function, the associated energy efficiency
value of points (see Table 5) will be assigned;
c) this assigned value of points of each function will be corrected based on their share of the
total power consumption of the accessory (see example with a dimmer below) to obtain the
corrected values;
d) the declaration of the EE class of the accessory is obtained by the sum of the corrected
values of each function;
e) declaration of the EE class according to Table 3.
The values and functions in the example of a dimmer below are chosen to demonstrate the
methodology only and do not represent existing accessories. The application of the
methodology to the different accessories and their respective values is the responsibility of the
relevant product committee.
An example of a dimmer with a Bluetooth communication function, a touch interface and a
timer is as follows.
The functions have different operating modes, which differ also in terms of the duration of usage.
An activity table shall first be defined as shown in Table 4.

Table 4 – Example of each function and the estimated time of usage for a dimmer
ON mode Standby mode
Function
% %
Dimming 30 70
RF 10 90
communication
(e.g. Bluetooth)
Touch 100 0
Timer 100 0
1) Identification of power consumption of each function:
– Dimming function: ON mode 300 mW
– Dimming function: standby mode 86 mW
– Bluetooth (RF communication): ON mode 100 mW
– Bluetooth (RF communication): standby mode 44 mW
– Touch function: ON mode 50 mW
– Timer function: ON mode  50 mW
2) Calculation of the consumption of the dimmer:
– Dimming function: ON mode 300 mW × 0,3 (= 30 %) = 90 mW
– Dimming function: standby mode 86 mW × 0,7 (= 70 %) = 60 mW
– Dimming function weighted 150 mW
– Bluetooth (RF communication): ON mode 100 mW × 0,1 = 10 mW
– Bluetooth (RF communication): standby mode 44 mW × 0,9 = 40 mW
– Bluetooth (RF communication) weighted 50 mW
– Touch function 50 mW
– Timer function 50 mW
Weighted power:
+ Dimming function weighted 150 mW
+ Bluetooth (RF communication) weighted 50 mW
+ Touch function 50 mW
+ Timer functions 50 mW
Total = 300 mW
3) Determine associated energy efficiency value of points for each function from Table 5:
– Dimming function 8 points (150 mW)
– Bluetooth (RF communication) 6 points (50 mW)
– Touch function 6 points (50 mW)
– Timer function 6 points (50 mW)
4) Evaluation of weighted energy efficiency points:
Corrective coefficient value = weighted power / total weighted power
– Dimming function 8 points × (150 mW/300 mW) = 4 points
– Bluetooth (RF communication) 6 points × (50 mW/300 mW) = 1 point
– Touch function 6 points × (50 mW/300 mW) = 1 point
– Timer functions 6 points × (50 mW/300 mW) = 1 point

– 14 – IEC 63172:2020 © IEC 2020
Energy efficiency points for EE class 7 points
5) Declaration of the EE class according to Table 3:
For 7 points, as calculated in step 4, EE class 2 is assigned.
Table 5 – Energy efficiency points
Product Function Device energy efficiency points
2 4 6 8 10
(mW) (mW) (mW) (mW) (mW)
Dimmers Dimming P > 400 300 < P ≤ 400 200 < P ≤ 300 100 < P ≤ 200 P < 100
Touch P > 100 60 < P ≤ 100 40 < P ≤ 60 20 < P ≤ 40 P < 20
RF communication P > 100 60 < P ≤ 100 40 < P ≤ 60 20 < P ≤ 40 P < 20
(e.g. Bluetooth)
Timer P > 100 60 < P ≤ 100 40 < P ≤ 60 20 < P ≤ 40 P < 20

Annex A
(informative)
Measuring methods
A.1 Measuring method – General
The applicable product standard for the different accessories should be taken into account; all
measurements should be done with the nominal supply voltage.
The measurement shall be carried out directly by means of a power meter, a power meter with
averaging function, or with other means adapted for the accessories.
It is recommended to short out the device which should be measured for calibrating both power
meters.
A.2 Dimmers
A.2.1 Three-wire dimmer (see Figure A.1)

Figure A.1 Three-wire dimmer measuring method
A.2.2 Two-wire dimmer (see Figure A.2)

Figure A.2 Two-wire dimmer measuring method

– 16 – IEC 63172:2020 © IEC 2020
A.2.3 Three-wire dimmer with mechanical switch load side (see Figure A.3)

Figure A.3 – Three-wire dimmer with mechanical switch measuring method
A.2.4 Two-wire dimmer with mechanical switch load side (see Figure A.4)

Figure A.4 – Two-wire dimmer with mechanical switch load side measuring method
A.3 Presence movement detector
A.3.1 Two-wire presence detector (see Figure A.5)

Figure A.5 – Two-wire presence detector measuring method

A.3.2 Three-wire
...