IEC 63345:2023

Energy efficiency systems - Simple external consumer display

IEC 63345:2023 specifies a data model to abstract the metering world towards a simple external consumer display. The data model, as described by means of functional blocks contained in this document, lays down the format of metering data accessible by a simple external consumer display. This data interface would be typically part of the meter communication functions and be accessed by a simple external consumer display via the H1 interface of CEN/CLC/ETSI TR 50572 between the display and the meter communication functions.

Systèmes pour l'efficacité énergétique – Affichage simple et externe du client

L'IEC 63345:2023 spécifie un modèle de données pour condenser l'ensemble des données de comptage dans un affichage simple et externe du client. Le modèle de données, décrit au moyen de blocs fonctionnels spécifiés dans le présent document, définit le format des données de comptage accessibles à l'aide d'un affichage simple et externe du client. Cette interface de données fait généralement partie des fonctions de communication du compteur et est accessible à partir d'un affichage simple et externe du client au moyen de l'interface H1 du CEN/CLC/ETSI TR 50572 située entre l'affichage et les fonctions de communication du compteur.

General Information

• Status: Published
• Publication Date: 19-Sep-2023
• ICS: 27.015 - Energy efficiency. Energy conservation in general
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: SC 23K - Electrical Energy Efficiency products
• Drafting Committee: WG 3 - TC 23/SC 23K/WG 3
• Current Stage: PPUB - Publication issued
• Start Date: 20-Sep-2023
• Completion Date: 20-Oct-2023

Standards Content (Sample)

IEC 63345 ®
Edition 1.0 2023-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Energy efficiency systems – Simple external consumer display

Systèmes pour l'efficacité énergétique – Affichage simple et externe du client

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IEC 63345 ®
Edition 1.0 2023-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Energy efficiency systems – Simple external consumer display

Systèmes pour l'efficacité énergétique – Affichage simple et externe du client

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.015, 29.020 ISBN 978-2-8322-7559-7

– 2 – IEC 63345:2023 © IEC 2023
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 9
4 Classification . 9
5 Requirements for the data interface . 11
5.1 General . 11
5.2 Minimization of data transmission . 13
5.3 Data consistency . 13
5.4 Filtering of message types and data points . 13
6 Conformity and testing . 13
7 Metering functional blocks of MDC. 14
7.1 MDC Heat Meter (M_HEATM) . 14
7.1.1 Aims and objectives . 14
7.1.2 Functional specification . 14
7.1.3 Constraints . 14
7.1.4 Data point overview . 14
7.2 MDC Heat cost allocator (M_HCA) . 16
7.2.1 Aims and objectives . 16
7.2.2 Functional specification . 16
7.2.3 Constraints . 16
7.2.4 Data point overview . 16
7.3 MDC Water meter (M_WATERM) . 17
7.3.1 Aims and objectives . 17
7.3.2 Functional specification . 17
7.3.3 Constraints . 18
7.3.4 Data point overview . 18
7.4 MDC Generic Meter (M_GENERICM) . 19
7.4.1 Aims and objectives . 19
7.4.2 Functional specification . 19
7.4.3 Constraints . 19
7.4.4 Data point overview . 19
7.5 MDC Gas Meter (M_GASM) . 21
7.5.1 Aims and objectives . 21
7.5.2 Functional specification . 21
7.5.3 Constraints . 21
7.5.4 Data point overview . 21
7.6 MDC Electricity Meter (M_ELECM) . 23
7.6.1 Aims and objectives . 23
7.6.2 Functional specification . 23
7.6.3 Constraints . 23
7.6.4 Data point overview . 23
7.7 MDC Breaker (M_BREAKERM) . 25

7.7.1 Aims and objectives . 25
7.7.2 Functional specification . 25
7.7.3 Constraints . 25
7.7.4 Data point overview . 25
7.8 MDC Valve (M_VALVEM) . 26
7.8.1 Aims and objectives . 26
7.8.2 Functional specification . 26
7.8.3 Constraints . 26
7.8.4 Data point overview . 26
8 Metering data model . 27
8.1 General . 27
8.2 Boolean value . 27
8.3 1-octet unsigned counter value . 28
8.4 Datapoint types "2-octet float value" . 28
8.5 2-octet unsigned counter value . 29
8.6 4-octet signed unsigned counter value . 29
8.7 4-octet signed time period . 30
8.8 Datapoint Type "MeteringValue" . 30
8.8.1 General . 30
8.8.2 Coding general . 30
8.8.3 Coding VallnfField . 31
8.8.4 Coding status . 32
8.8.5 Recommended display format for metering data . 33
8.9 DPT Active Energy . 34
8.10 DPT for tariff information . 34
8.11 DPT Currency . 35
8.12 DPTs for price information . 35
8.13 Format of DPT_DateTime . 36
8.13.1 Coding . 36
8.13.2 Remarks to the coding of DPT_DateTime . 38
8.14 Datapoint type DPT_Metering_DeviceType . 39
8.15 Datapoint type Character Set . 40
8.16 Datapoint type DPT_VarString_8859_1 . 41
8.17 DPT_Gas_Measurement_condition . 42
8.18 Datapoint type DPT_Meter_BreakerValve_State . 43
8.19 Datapoint type DPT_Meter_Mode . 43
8.20 Datapoint type DPT_Power_Threshold_Status . 44
8.21 Datapoint type DPT_Battery_Status . 45
Annex A (informative) Cross reference mapping this document and COSEM/OBIS . 46
A.1 General . 46
A.2 Generic data points: MDC Generic Meter (M_GENERICM) . 46
A.3 Electricity data points: MDC Electricity Meter (M_ELECM) . 49
A.4 MDC heat heatmeter (M_HEATM) . 56
A.5 MDC Heat Cost Allocator (M_HCA) . 62
A.6 MDC Water Meter (M_WATERM) . 66
A.7 MDC Gas Meter (M_GASM) . 71
A.8 MDC Valve (M_VALVEM) . 75
Bibliography . 78

– 4 – IEC 63345:2023 © IEC 2023
Figure 1 – Metering system topology from CEN/CLC/ETSI/TR 50572 . 10

Table 1 – Measurable quantities . 11
Table 2 – Data point overview M_HEATM . 14
Table 3 – Data Point overview M_HCA . 16
Table 4 – Data point overview M_WATERM . 18
Table 5 – Data point overview M_GENERICM . 20
Table 6 – Data point overview M_GASM . 21
Table 7 – Data point overview M_ELECM . 23
Table 8 – Data point overview M_BREAKERM . 25
Table 9 – Data point overview M_VALVEM . 27
Table 10 – Boolean value . 28
Table 11 – 1-octet unsigned counter value . 28
Table 12 – Datapoint types "2-octet float value" . 29
Table 13 – 2-octet unsigned counter value . 29
Table 14 – 4-octet signed unsigned counter value . 30
Table 15 – 4-octet signed time period . 30
Table 16 – Coding general . 31
Table 17 – Coding VallnfField . 32
Table 18 – Coding status . 33
Table 19 – Display format for metering data . 34
Table 20 – DPT Active Energy . 34
Table 21 – DPT for tariff information . 35
Table 22 – DPT Currency. 35
Table 23 – DPTs for price information . 36
Table 24 – Coding of DPT_DateTime . 36
Table 25 – Datapoint type DPT_Metering_Device Type . 40
Table 26 – Datapoint type Character Set . 41
Table 27 – Datapoint type DPT_VarString_8859_1 . 42
Table 28 – DPT_Gas_Measurement_Condition . 42
Table 29 – Datapoint type DPT_Meter_BreakerValve_State . 43
Table 30 – Datapoint type DPT_Meter_Mode . 44
Table 31 – Datapoint type DPT_Power_Threshold_Status . 44
Table 32 – Datapoint type DPT_Battery_Status . 45
Table A.1 – MDC Generic Meter (M_GENERICM) . 46
Table A.2 – MDC Electricity Meter (M_ELECM). 49
Table A.3 – MDC Heat Heatmeter (M_HEATM) . 56
Table A.4 – MDC Heat Cost Allocator (M_HCA) . 62
Table A.5 – MDC Water Meter (M_WATERM) . 66
Table A.6 – MDC Gas Meter (M_GASM) . 71
Table A.7 – MDC Valve (M_VALVEM) . 75

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ENERGY EFFICIENCY SYSTEMS –
SIMPLE EXTERNAL CONSUMER DISPLAY

FOREWORD
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IEC 63345 has been prepared by subcommittee 23K: Electrical energy efficiency products, of
IEC technical committee 23: Electrical accessories. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
23K/87/FDIS 23K/89/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
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The language used for the development of this International Standard is English.
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– 6 – IEC 63345:2023 © IEC 2023
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INTRODUCTION
The reduction of CO emissions is one the most challenging tasks today.
Providing the consumers with more information about their energy usage will allow them to
make more informed choices and hence reductions.
Standardizing the communications interfaces between the metering systems and display will
allow interoperability between the meter and display.

– 8 – IEC 63345:2023 © IEC 2023
ENERGY EFFICIENCY SYSTEMS –
SIMPLE EXTERNAL CONSUMER DISPLAY

1 Scope
This document specifies a data model to abstract the metering world towards a simple external
consumer display. The data model, as described by means of functional blocks contained in
this document, lays down the format of metering data accessible by a simple external consumer
display. This data interface would be typically part of the meter communication functions and
be accessed by a simple external consumer display via the H1 interface of
CEN/CLC/ETSI TR 50572 between the display and the meter communication functions.
The data interface specified in this document may also be accessed by the LNAP or NNAP
through the C or M interface, after which the data could be accessed by HBES devices through
the H2 and H3 interfaces.
In other words, in this way the same data model can be used both on the H1 as well as the H2
and H3 interfaces.
This document does not specify the communication mechanisms used on the data interface,
nor the applied data privacy and security mechanisms, nor the ergonomics of the simple
external consumer displays, where national regulations can apply.
The document does also not specify the communication protocol used between the meters and
the meter communication functions. However, it takes into account existing standards such as
the EN 13757 series (in particular EN 13757-3:2018 and its Annex H) and the IEC 62056 series
for the definition of the data model.
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.
ISO/IEC 8859-1, Information technology – 8-bit single-byte coded graphic character sets –
Part 1: Latin alphabet No. 1
ISO 4217, Codes for the representation of currencies
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp

3.1.1
meter
instrument for measuring, memorizing and displaying data related to the consumption of a
commodity
3.1.2
data point
container element, in which information is located related to a function of a product (in e.g.
memory or a register)
3.2 Abbreviated terms
Cs company specific
FB functional block
NA not allowed/not applicable
HVAC heating ventilation air conditioning
VIF/VIFE value information field/value information field extensions
C used to connect LNAPs and/or metering end devices to an NNAP
NOTE Typical interface technologies are for example (not limited to) narrowband PLC communication
networks, local wired or wireless networks.
H1 interface which connects a metering end device to a simple external consumer
display
H2 interface which connects a LNAP with auxiliary devices, for example a home
automation or advanced display functionality
H3 connects an NNAP with auxiliary devices, for example a home automation or
advanced display functionality
LNAP local network access point
L optional interface which allows an LNAP to be connected to zero or more peer
LNAPs
N optional interface which allows an NNAP to be connected to zero or more NNAPs
NNAP neighbourhood network access point
A NNAP is a functional entity that, when equipped with C interface, allows access
to one or more LNAPs or metering end devices and, when equipped with an H3
interface (interfaces), to advanced display/home automation end devices connected
to the NN.
A NNAP may also allow data exchange between different functional entities
connected to the same NN. The gateway functionality of the NNAP provides a
connectivity infrastructure between meters and the central system. It utilizes two
separate communication networks. It communicates with the central system via a
WAN, and via a NN with the meters and/or LNAPs which it manages.
M M interface (metering end device interface), which is between the communications
function of the meter and the LNAP or between metering end devices. The interface
defines the access of external devices to internal data on the meter.
MDC meter data concentrator
DPT data point
4 Classification
Clause 4 is intended to show the general reference model in Figure 1.

– 10 – IEC 63345:2023 © IEC 2023

Figure 1 – Metering system topology from CEN/CLC/ETSI/TR 50572
In this document, a functional block is specified for each typical metering function, grouping a
number of in- and output data points, as depicted in Figure 1.
Figure 1 depicts logical entities and not physical devices.
NOTE 1 This document does not define requirements for devices acting as data sources for the simple external
consumer display (devices sending input on the I interface shown in Figure 1). These requirements are covered by
other European standards.
In line with the architecture shown in Figure 1, the information flow on the H1 interface is
predominantly from the meter communication function in one or more meters to one or more
simple external consumer displays (or optionally one common display), whereby the latter acts
as sink of the information obtained through the H1 interface from the meter communication
functions. Where necessary, the consumer display may poll data from the meter communication
functions, for example historical values. In no case shall it be able to alter metering data through
the consumer display. Hence, most functional blocks of the data interface specified in this
document contain data that are intended as output data to a connected display.
The data structures used on the H1 interface are part of this document. All other underneath
described interfaces are informative.
NOTE 2 The wired meter communication according to EN 13757-2 is only applicable if it is used exclusively for the
H1 interface.
The functional blocks specified in this document may also be accessed by the LNAP or NNAP
through the C or M interface, after which the data could be accessed bi-directionally with HBES
devices through the H2 and H3 interfaces.
The communication on the H2 and H3 interfaces is out of scope of this document
For each connected metering function, the corresponding metering communication function
shall hold an entity of the corresponding functional block. The input for each connected metering
function is supplied by meters and is not part of this document.
The input to the LNAP and NNAP is due to be part of the IEC 62746 series.
The measurable quantities shown in Table 1 can be represented in the data interface through
the listed functional blocks (FB):
Table 1 – Measurable quantities
Physical media FB
Other M_GENERICM
Oil M_GENERICM
Electricity M_ELECM
Gas M_GASM b)
Heat (outlet) M_HEATM
Steam M_GENERICM
Warm water (30°C to 90°C) M_WATERM
Water M_WATERM
Heat cost allocator M_HCA
Cooling load meter (outlet) M_HEATM
Cooling load meter (inlet) M_HEATM
Heat (inlet) M_HEATM
Heat and cool M_HEATM
Breaker M_BREAKERM
Valve M_VALVEM
Waste water meter M_WATERM
Annex A provides, for information, a cross-reference mapping between this document and
COSEM/OBIS.
5 Requirements for the data interface
5.1 General
Each metering function shall be represented by a corresponding functional block, typically part
of the metering communication function and accessed by a simple user display.
Some meters may also provide metering data history values (e.g. monthly data). It is highly
recommended that, for each meter, a limited set of history values is available, for example
covering the previous week, previous month or previous year.
Depending on national regulations, it can be necessary that some of the data survive power
down situations.
– 12 – IEC 63345:2023 © IEC 2023
In case of one common display unit supporting multiple meter devices, during installation and
teach-in procedures of metering devices, a meter device directory shall be created to assign
linked meters.
The format and management of the metering device directory is company and/or protocol
specific and not part of this document. Appropriate procedures shall be provided to
– add a new metering device,
– replace a metering device by another device (with different identification number and e.g.
different unit/resolution of the metering data), and
– delete a metering device.
The above workflow shall be supported by appropriate means (e.g. device localization via
display, text information, etc.).
Two data points, "MeterReplacement" and "MeterReplacementCounter", are defined for each
metering functional block to detect and manage replacement of metering devices. Further
company specific mechanisms can be implemented to simplify the meter replacement workflow.
For each meter, a "UserText" may be configured to simplify identification and localization of the
meter. This "UserText" can be useful in case of
– service, maintenance,
– binding of metering data to displays.
– billing information for the end user,
– etc.
In case of removal or deletion of a metering device from the device directory, it is highly
recommended to keep the corresponding instance of the functional block alive and set all data
in the functional block to void values (see below). It is not recommended to re-assign functional
block indices of the remaining functional blocks because data processing by the data display
could be corrupted.
After commissioning or power up, metering data can be void or outdated for hours until a new
message from a metering device is received by the metering communication function.
On customer move out, certain data may need to be made unavailable for the next customer.
On supplier change, certain data needs to be made unavailable for the next supplier.
The "OutOfService" status attribute in metering data points shall indicate void data. This status
attribute may be set in the following cases:
– no metering device is connected to the metering functional block (ex factory default data);
– a previously connected metering device is removed or deleted from the device directory.
Handling of the metering device directory is manufacturer specific.
In case of meter replacement, all metering data in the corresponding functional block shall be
set to void as upon removal of the previous meter until the first valid metering data message
from the new device is received. This may take several hours.
NOTE This document does not foresee specific mechanisms to supervise the presence/function of connected
metering devices using life-check mechanisms etc. Because of very manufacturer specific cyclic update periods for
metering messages, a life-check "timeout" cannot be standardized. Therefore, this document does not put
requirements to set metering data automatically "OutOfService" in case of missing/outdated data from the connected
metering device.
The simple user display can access metering data by
– polling of functional blocks and data points,
– regularly by data being pushed to the display, or
– notifications or messages (e.g. sent by an external actor or generated by the meter). Data
structures for this type of messages are not specified in this document.
5.2 Minimization of data transmission
Meter data comprises data that change infrequently and some that change frequently. The data
transmission rate shall reflect the frequency with which the data is expected to change. In the
case the data is polled, the user display shall not access a next data point value before the
meter communication function has responded to the previous data point access, unless the
meter communication function did not respond to the user display's request within a time that
can be set manufacturer specific.
5.3 Data consistency
During polling of metering data, new metering data may be received and read out data may be
inconsistent. For data consistency, checking each metering functional block shall provide a data
point "RxSequenceCounter" that shall be incremented each time new metering data is received
from the corresponding metering device.
The user display reading out metering data shall check the "RxSequenceCounter" counter
before and after read out of the complete set of metering data. If the sequence counter value
has changed, metering data may be inconsistent. The user display shall then retry the
procedure.
5.4 Filtering of message types and data points
For a display, only a few message types are relevant. The special Request/Respond messages
used for the Gateway to request special data are not relevant for a simple external consumer
display. For the presentation of the data, the spontaneous meter messages with C=44h are
recommended. Also C=46h or 06h could be taken into account, as they constitute special
messages for installation purposes.
All other message types should be ignored. If a message is ignored, the reception time stamp
"RxReceptionTime" shall not be changed.
It is recommended to limit the number of supported VIF/VIFE for a consumer display.
The following data points may be excluded from the interpretation:
– plain text VIF 7Ch/FCh, as used for very uncommon units;
– manufacturer specific VIFs 7Fh/FFh;
– extension table FDh.
The manufacturer shall consider to also limit the number of supported units from the extension
table FBh.
6 Conformity and testing
The requirements for the data interface between the meter communication function and a simple
user display are given in Clause 5.

– 14 – IEC 63345:2023 © IEC 2023
The measurable quantity or quantities determine the need to implement the functional blocks
as given in Table 1. If a certain function of the functional blocks as described in the relevant
subclause of Clause 7 is implemented, then the data structures shall comply with the format as
given in Clause 8. If a certain function is added that is not described in functional blocks as
given in Clause 7, the data structures used may be manufacturer or country specific.
Testing of compliance consist in the checking of the correct implementation of the (different
parts) of the data structures. As this document does not describe the communication protocols
used to transport the specified data structures, testing of compliance of the implemented data
structures may have to be performed with testing tools that are specific to the used
communication protocol.
7 Metering functional blocks of MDC
7.1 MDC Heat Meter (M_HEATM)
7.1.1 Aims and objectives
The functional block "MDC Heat Meter" shall contain heat meter data (Device Type = 4, 10 to
13 – see 8.14).
NOTE The same functional block also covers measurement of cooling energy.
7.1.2 Functional specification
The data points of the functional block representing heat meter data can be accessed by the
display.
7.1.3 Constraints
Only a subset of metering data may be accessible by the display. The effective number of data
that is provided by meters is company specific.
7.1.4 Data point overview
Table 2 shows a data point overview of M_HEATM.
Table 2 – Data point overview M_HEATM
Datapoint Description Datapoint Type
CurrentEnergyConsumption Accumulated energy value DPT_MeteringValue
TempFlowWater Current flow temperature DPT_Value_Temp
TempReturnWater Current return temperature DPT_Value_Temp
TempDiffWater Current temperature difference DPT_Value_Tempd
ReliabilityOfMeteringData Indicates whether metering data are up-to- DPT_Bool
date or outdated.
CurrentPower Current measured power DPT_MeteringValue
CurrentVolumeFlow Current measured volume flow DPT_MeteringValue
CurrentEnergyConsumption_T1 Current energy consumption Tarif 1 DPT_MeteringValue
HistoryStorageNumbers Array of storage numbers for history values DPT_Value_1_Ucount[n]
HistoryDate Array of date/time information for history DPT_DateTime[n]
values
HistoryEnergyConsumption Array of energy consumption history values DPT_MeteringValue[n]
HistoryEnergyConsumption_T1 Array of energy consumption tarif 1 history DPT_MeteringValue[n]
values
HistoryVolumeMaxFlow Array of max. volume flow history values DPT_MeteringValue[n]

Datapoint Description Datapoint Type
HistoryVolumeMinFlow Array of min. volume flow history values DPT_MeteringValue[n]
HistoryMaxPower Array of max. power history values DPT_MeteringValue[n]
HistoryMinPower Array of min. power history values DPT_MeteringValue[n]
RxSequenceCounter Sequence counter generated locall
...