IEC 62888-1:2018

Railway applications - Energy measurement on board trains - Part 1: General

IEC 62888-1:2018 describes the primary purpose of the Energy Measurement System (EMS), which measures energy consumption on board for applications such as energy management, energy saving, billing and others. It gives requirements for the complete EMS and also requirements for all devices implementing one or more functions of the EMS; applies to newly manufactured EMSs for use on board traction units, powered by AC and/or DC supply voltages as listed in IEC 60850.

Applications ferroviaires - Mesure d’énergie à bord des trains - Partie 1: Généralités

L'IEC 62888-1:2018 décrit le principal objectif du système de mesure d’énergie (EMS) qui mesure la consommation d'énergie à bord pour des applications telles que la gestion de l’énergie, les économies d’énergie, la facturation, etc. Cette norme définit les exigences générales pour l’EMS complet ainsi que les exigences pour tous les dispositifs mettant en œuvre une ou plusieurs fonctions de l’EMS; elle’applique à des EMS nouvellement fabriqués pour l’utilisation à bord d’unités de traction alimentées par des tensions d’alimentation en courant alternatif et/ou en courant continu comme indiqué dans l’IEC 60850.

General Information

• Status: Published
• Publication Date: 24-Jan-2018
• ICS: 45.060.01 - Railway rolling stock in general
• Technical Committee: TC 9 - Electrical equipment and systems for railways
• Drafting Committee: MT 62888 - TC 9/MT 62888
• Current Stage: PPUB - Publication issued
• Start Date: 25-Jan-2018
• Completion Date: 29-Dec-2017

Overview

IEC 62888-1:2018, titled Railway applications - Energy measurement on board trains - Part 1: General, is an international standard developed by the International Electrotechnical Commission (IEC). It defines the fundamental requirements for the Energy Measurement System (EMS) installed on board railway traction units powered by AC and/or DC supply voltages, as specified in IEC 60850. The EMS is designed to measure energy consumption and support diverse applications including energy management, energy saving, billing, and others. This standard sets out the system-level and device-level requirements crucial for the accurate and reliable functioning of EMS in the railway sector.

Key Topics

The standard provides a comprehensive framework covering:

• Scope & Application: Applies to newly manufactured EMS technology used on traction units for onboard energy measurement.
• Energy Measurement System Requirements:
  • System-level requirements include accuracy, operation, power supply, measuring inputs, data handling, and reliability (RAMS – Reliability, Availability, Maintainability, Safety).
  • Device-level requirements address marking, essential data availability, interfaces, data processing, software, security, environmental, mechanical, and electrical criteria.
• Functional Structure: EMS functions are divided into measurement, data handling, communication, and conformance testing (expanded in subsequent parts of the IEC 62888 series).
• Performance Levels: Defines levels of accuracy and system responsiveness required for reliable energy measurement on trains.
• Conformance & Testing: Addresses the consistent quality and verification procedures to ensure EMS meets international expectations.
• Terminology & Definitions: Sets standard terms and abbreviations for consistency across stakeholders.

Applications

IEC 62888-1:2018 is critical for organizations involved in the design, manufacturing, installation, and operation of onboard energy measurement systems in railway vehicles. Specific applications include:

• Energy Management: Accurate energy consumption data supports efficient energy use and optimization for train operators.
• Energy Saving Initiatives: Enables identification of energy-saving opportunities and validates energy conservation measures.
• Billing and Accounting: Provides precise energy consumption data to support fair and transparent billing between energy providers and railway operators.
• Technical Research and Development: Facilitates R&D activities aiming to improve energy efficiency and performance monitoring.
• Safety and Reliability Assessments: Ensures that EMS components meet stringent railway safety and reliability standards.

The standard supports interoperability and enables flexible EMS architecture, allowing railway operators and manufacturers to customize EMS physical implementations according to operational needs while adhering to a unified functional framework.

Related Standards

IEC 62888-1:2018 is part of a comprehensive IEC 62888 series covering all aspects of onboard energy measurement for trains, including:

• IEC 62888-2 – Energy Measurement: Detailed specifications for energy measurement and metrology of current, voltage, and energy calculations.
• IEC 62888-3 – Data Handling: Requirements for onboard data processing, storage, and preparation for communication to ground systems.
• IEC 62888-4 – Communication: Guidelines for communication protocols and interfaces, including onboard and ground data exchanges.
• IEC 62888-5 – Conformance Test: Defines verification procedures to ensure compliance of EMS devices and systems.
• IEC 62888-6 – Requirements for Purposes Other Than Billing: Addresses EMS applications such as benchmarking and daily consumption monitoring beyond billing.

Additionally, the EMS aligns with IEC 60850, which defines supply voltages for traction units, ensuring compatibility with power supply standards. The standard is developed in cooperation with ISO/IEC directives and closely follows international best practices for electrical and electronic railway equipment.

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Keywords: IEC 62888-1, energy measurement system, railway applications, onboard trains, energy management, energy consumption measurement, traction units, electrical standards, IEC 60850, railway energy saving, EMS conformance, data handling system, energy billing, railway metrology.

Standards Content (Sample)

IEC 62888-1 ®
Edition 1.0 2018-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Railway applications – Energy measurement on board trains –
Part 1: General
Applications ferroviaires – Mesure d'énergie à bord des trains –
Partie 1: Généralités
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IEC 62888-1 ®
Edition 1.0 2018-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Railway applications – Energy measurement on board trains –

Part 1: General
Applications ferroviaires – Mesure d'énergie à bord des trains –

Partie 1: Généralités
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 45.060.01 ISBN 978-2-8322-5161-4

– 2 – IEC 62888-1:2018 © IEC 2018
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 9
3.1 Terms and definitions . 9
3.2 Abbreviated terms . 11
4 Requirements . 12
4.1 General . 12
4.2 System level requirements . 12
4.2.1 General . 12
4.2.2 Accuracy . 12
4.2.3 EMS operation and power supply . 13
4.2.4 EMS measuring input . 13
4.2.5 Data handling . 14
4.2.6 Reliability, Availability, Maintainability and Safety (RAMS) . 15
4.3 Device level requirements . 16
4.3.1 Marking and availability of essential data . 16
4.3.2 Interfaces . 16
4.3.3 Data processing and transfer . 18
4.3.4 Software . 18
4.3.5 Dataflow security . 19
4.3.6 Environmental conditions . 19
4.3.7 Mechanical requirements, construction and design . 21
4.3.8 Electrical requirements . 22
Bibliography . 24

Figure 1 – EMS functional structure and dataflow diagram . 7

Table 1 – Levels of performance . 12
Table 2 – Power-up time classes . 13
Table 3 – Traction supply system change classes . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS –
ENERGY MEASUREMENT ON BOARD TRAINS –

Part 1: General
FOREWORD
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International Standard IEC 62888-1 has been prepared by IEC technical committee 9:
Electrical equipment and systems for railways.
This standard is based on EN 50463.
The text of this International Standard is based on the following documents:
FDIS Report on voting
9/2320/FDIS 9/2331/RVD
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.

– 4 – IEC 62888-1:2018 © IEC 2018
A list of all parts in the IEC 62888 series, published under the general title Railway
applications – Energy measurement on board trains, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
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the specific document. At this date, the document will be
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• withdrawn,
• replaced by a revised edition, or
• amended.
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INTRODUCTION
Three levels are introduced for categorizing EMS as described in 4.1.
This is Part 1 of the IEC 62888 series which consists of the following parts, under the general
title Railway applications – Energy measurement on board trains:
Part 1: General
Part 2: Energy measurement
Part 3: Data handling
Part 4: Communication
Part 5: Conformance test
Part 6: Requirements for purposes other than billing
This series of International Standards follows the functional guidelines description in Annex A,
“Principles of conformity assessment”, of ISO/IEC 17000:2004 tailored to the Energy
Measurement System (EMS).
The Energy Measurement System (EMS) provides measurement and data suitable for
applications such as energy management, energy saving, billing and others.
This series of International Standards uses the functional approach to describe the EMS.
These functions are implemented in one or more physical devices. The user of this series of
standards is free to choose the physical implementation arrangements.
Structure and main contents of the IEC 62888 series
This series of International Standards is divided into six parts. The titles and brief descriptions
of each part are given below:
IEC 62888-1 – General
The scope of IEC 62888-1 is the Energy Measurement System (EMS).
IEC 62888-1 provides system level requirements for the complete EMS and common
requirements for all devices implementing one or more functions of the EMS.
IEC 62888-2 – Energy measurement
The scope of IEC 62888-2 is the Energy Measurement Function (EMF).
The EMF provides measurement of the consumed and regenerated active energy of a traction
unit. If the traction unit is designed for use on AC traction supply systems, the EMF also
provides measurement of reactive energy. The EMF provides the measured quantities via an
interface to the Data Handling System.
The EMF consists of the three functions: Voltage Measurement Function, Current
Measurement Function and Energy Calculation Function. For each of these functions,
accuracy classes are specified and associated reference conditions are defined. This part
also defines all specific requirements for all functions of the EMF.
The Voltage Measurement Function measures the voltage of the contact line (CL) system and
the Current Measurement Function measures the current taken from and returned to the CL
system. These functions provide signal inputs to the Energy Calculation Function.

– 6 – IEC 62888-1:2018 © IEC 2018
The Energy Calculation Function inputs the signals from the Current and Voltage
Measurement Functions and calculates a set of values representing the consumed and
regenerated energies. These values are transferred to the Data Handling System and are
used in the creation of Compiled Energy Measured Data.
All relevant metrological aspects are covered in this part of IEC 62888.
IEC 62888-2 also defines the conformance test of the EMF.
IEC 62888-3 – Data handling
The scope of IEC 62888-3 is the Data Handling System (DHS).
The on board DHS receives, produces and stores data, ready for transmission to any
authorised receiver of data on board or on ground. The main goal of the DHS is to produce
Compiled Energy Measured Data and transfer it to an on-ground Data Collection Service
(DCS). The DHS can support other functionality on board or on-ground with data, as long as
this does not conflict with the main goal.
IEC 62888-3 also defines the conformance test of the DHS.
IEC 62888-4 – Communication
The scope of IEC 62888-4 is the communication services.
This part of IEC 62888 gives requirements and guidance regarding the data between the
functions implemented within EMS as well as between such functions and other on board
units where data are exchanged using a communications protocol stack over a dedicated
physical interface or a shared network.
It includes the on board to ground communication service and covers the requirements
necessary to support data transfer between DHS and DCS.
IEC 62888-4 also defines the conformance test of the communications services.
IEC 62888-5 – Conformance test
The scope of IEC 62888-5 is the conformance test procedures for the EMS.
IEC 62888-5 also covers re-verification procedures and conformance test in the event of the
replacement of a device of the EMS.
IEC 62888-6 – Requirements for purposes other than billing
The scope of IEC 62888-6 is to specify the requirements for EMS to be used for
benchmarking, daily energy consumption monitoring, technical research and development.
This part provides the requirements for monitoring consumed energy on board in daily
services in an easy way and the measured data are applicable for general purposes in
industry such as energy management, energy saving, etc. However, this part is not applicable
for billing purposes.
EMS functional structure and dataflow
Figure 1 illustrates the functional structure of the EMS, the main sub-functions and the
structure of the dataflow and is informative only. Only the main interfaces required by this
standard are displayed by arrows.
Since the communication function is distributed throughout the EMS, it has been omitted for
clarity. Not all interfaces are shown.
Other Systems
Time Reference Source
Settlement
Location Reference Source
System
Data Storage Function
Current Measurement Function
Voltage Measurement Function
Data
Data Compilation Function
Energy Calculation Function
Collection
Service
Energy Measurement Function Data Handling System (DCS)
(EMF) (DHS)
IEC 62888-2 (Energy Measuring) IEC 62888-3 (Data Handling)
Energy Measurement System (EMS)
IEC 62888-1 (General), IEC 62888-4 (Communication), IEC 62888-5 (Conformance test),
IEC 62888-6 (Requirements for purposes other than billing) Other
Systems
On-board (Traction Unit)
On-ground
IEC
Figure 1 – EMS functional structure and dataflow diagram

– 8 – IEC 62888-1:2018 © IEC 2018
RAILWAY APPLICATIONS –
ENERGY MEASUREMENT ON BOARD TRAINS –

Part 1: General
1 Scope
This part of IEC 62888 describes the primary purpose of the Energy Measurement System
(EMS), which measures energy consumption on board for applications such as energy
management, energy saving, billing and others.
This part of IEC 62888:
• gives requirements for the complete EMS and also requirements for all devices
implementing one or more functions of the EMS;
• applies to newly manufactured EMSs for use on board traction units, powered by AC
and/or DC supply voltages as listed in IEC 60850;
• does not apply to portable EMSs.
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.
IEC 60085, Electrical insulation – Thermal evaluation and designation
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
IEC 60529:1989/AMD1:1999
IEC 60529:1989/AMD2:2013
IEC 60571:2012, Railway applications – Electronic equipment used on rolling stock
IEC 60850, Railway applications – Supply voltages of traction systems
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
IEC 61991, Railway applications – Rolling stock – Protective provisions against electrical
hazards
IEC 62497-1:2010, Railway applications – Insulation coordination – Part 1: Basic
requirements – Clearances and creepage distances for all electrical and electronic equipment
IEC 62497-1:2010/AMD1:2013
IEC 62498-1:2010, Railway applications – Environmental conditions for equipment – Part 1:
Equipment on board rolling stock
IEC 62847, Railway applications – Rolling stock – Electrical connectors – Requirements and
test methods
IEC 62888-2, Railway applications – Energy measurement on board trains – Part 2: Energy
measurement
IEC 62888-4, Railway applications – Energy measurement on board trains – Part 4:
Communication
IEC 62888-6, Railway applications – Energy measurement on board trains – Part 6:
Requirements for purposes other than billing
ISO 3166-1, Codes for the representation of names of countries and their subdivisions – Part
1: Country codes
ISO 13732-1, Ergonomics of the thermal environment – Methods for the assessment of human
responses to contact with surfaces – Part 1: Hot surfaces
3 Terms, definitions and abbreviated terms
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 Terms and definitions
3.1.1
authenticity
state in which information is valid and known to have originated from the stated source
[SOURCE: IEC 60050-821: 2017, 821-11-05]
3.1.2
compiled energy measured data
CEMD
dataset compiled by the DHS suitable for energy management
3.1.3
CEMD-related data
all data produced by any function of the EMS required for the production of CEMD
Note 1 to entry: This includes voltage data, current data, energy data, time data and location data.
3.1.4
Consumption Point Identification
CPID
code uniquely identifying each EMS installed on the traction unit
3.1.5
Contact Line
CL
conductor system for supplying electric energy to a traction unit through current-collecting
equipment
[SOURCE: IEC 60050-811: 2017, 811-33-01, modified:"vehicles" changed to "traction unit"]

– 10 – IEC 62888-1:2018 © IEC 2018
3.1.6
Current Measurement Function
CMF
function of an EMF measuring the current taken from and returned to the CL by the traction
unit
3.1.7
Data Collection Service
DCS
on ground service collecting the CEMD from an EMS
3.1.8
Data Handling System
DHS
function combining the energy data produced by an EMF with other data, storing and
transmitting the data to a DCS and other systems
3.1.9
enclosure
housing affording the type and degree of protection suitable for the intended application
[SOURCE: IEC 60050-195:1998, 195-02-35]
3.1.10
Energy Calculation Function
ECF
function calculating energy data using input signals from the VMF and CMF
3.1.11
energy data
set of measured energy values transferred from EMF to DHS
3.1.12
Energy Measurement Function
EMF
function comprising the voltage measurement function, the current measurement function and
the energy calculation function
3.1.13
Energy Measurement System
EMS
on board system comprising the EMF, DHS and associated communications services
3.1.14
equipment type
mode of action or activity by which a product fulfils its purpose
Note 1 to entry: Equipment is designated by the manufacturer by one or more groups of letters or numbers, or a
combination of letters and numbers. Each equipment type has one designation only.
Note 2 to entry: The equipment type is represented by the equipment sample as provided for type test.
Note 3 to entry: Functions can be VMF, CMF, ECF, EMF, DHS or EMS or any combination of these functions.
3.1.15
function
mode of action or activity by which a product fulfils its purpose
[SOURCE: IEC 60050-821: 2017, 821-12-25]

3.1.16
interface
link between two functions of the EMS or between the EMS and other functions
Note 1 to entry: A link can be physical or virtual.
3.1.17
purchaser
entity that is a recipient of the EMS or parts of the EMS provided by a supplier
3.1.18
supplier
entity that supplies EMS or parts of the EMS
Note 1 to entry: The manufacturer may also play the role of supplier.
3.1.19
traction unit
vehicle or group of vehicles in fixed formation, for which the energy taken from and/or
returned to the CL is to be measured by an EMS
Note 1 to entry: IEC 62888 uses the term ‘traction unit’ to describe the part of a train to which energy metering is
applied. The term ‘traction unit’ is considered to be a more suitable term than ‘vehicle’ because the latter term is
generally used to describe the smallest part of a train, i.e. an individual vehicle.
3.1.20
Voltage Measurement Function
VMF
function of an EMF measuring the voltage of the CL
3.1.21
Vehicle Identification Number
VIN
code uniquely identifying each vehicle
Note 1 to entry: For European countries it is represented by the European vehicle number (unique 12 digit
identification number) as defined in the decision 2011/314/EU.
3.2 Abbreviated terms
CEMD Compiled Energy Measured Data
CL Contact Line
CMF Current Measurement Function
CPID Consumption Point Identification
DCS Data Collection Service
DHS Data Handling System
ECF Energy Calculation Function
EMF Energy Measurement Function
EMS Energy Measurement System
RAMS Reliability, Availability, Maintainability and Safety
VIN Vehicle Identification Number
VMF Voltage Measurement Function

– 12 – IEC 62888-1:2018 © IEC 2018
4 Requirements
4.1 General
Clause 4 of this document describes the requirements of an energy measurement system
(EMS).
4.2 gives system level requirements for the complete EMS.
4.3 gives common requirements for all devices implementing one or more functions of the
EMS.
The EMS is categorized in one of the following 3 levels of performance, see Table 1.
Table 1 – Levels of performance
Levels Description Notes
Level 1 Level for measuring energy consumption on board for This is the only level applicable for
applications like energy management, energy saving, billing billing.
and others.
Level 2 Level for measuring energy consumption on board for Level 2 is applied when accuracy
applications like energy management, energy saving, requirements need to be raised to
benchmarking among suppliers or train operators and others. ones equivalent to level 1 by
This level is not applicable for billing. agreement among the Parties for
international comparison or
benchmarking purposes.
Level 3 Level for daily energy measurement, for instance: technical -based on users requests.
research and development. This Level is not applicable for
-Both measuring performance and
billing.
service conditions can be less
severe than level 1.
Power and energy are calculated
based on voltage and current data
acquired from existing sensors
installed in converter systems, etc.

Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.
4.2 System level requirements
4.2.1 General
If an EMS has any functions which are additional to those specified in IEC 62888, then these
functions shall not:
• affect the accuracy,
• degrade the operation of the EMS, and
• influence the production and storage of compiled energy measured data (CEMD) and
CEMD-related data.
Any changes to configuration shall be logged in the EMS or document, and the device
marking and stored information shall also be updated.
4.2.2 Accuracy
The energy measurement accuracy is defined by the functions of the EMF and shall be
determined in accordance with IEC 62888-2.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.

4.2.3 EMS operation and power supply
4.2.3.1 General
The EMS shall be fully operational whenever energy flows from or to the contact line (CL).
Any part of the EMS powered by an auxiliary power supply, shall be compatible with the
requirements of IEC 60571:2012 regarding power supply characteristics.
The rated power supply voltage and maximum power consumption of the EMS shall be stated.
4.2.3.2 Power-up
Following the application of the power supply, the EMS shall achieve operational status and
be ready to measure energy within time of Table 2.
Table 2 – Power-up time classes
Power-up classes Power up time
s
PWR-A 60
PWR-B 120
PWR-X Agreed between the involved parties

Unless otherwise specified, the requirements of class PWR-A apply.
NOTE 1 The application of power to the EMS is an installation design consideration.
NOTE 2 The 60 s maximum time limit has been selected because the power-up procedure for traction units
typically requires several minutes to elapse between switching on the vehicles ancillary supplies and any
significant amount of energy being drawn from the CL.
4.2.3.3 Power-down
In the event of intentional loss of power to the EMS, no CEMD and other data shall be lost.
Unintentional loss of power shall not affect data stored in the EMS.
The EMS could include a procedure for transmitting all unsent CEMD to data collection
service (DCS) as part of a planned power-down procedure of the EMS. This can help to
support timely data processing on-ground.
4.2.4 EMS measuring input
4.2.4.1 Installation point of the VMF and CMF
The position of the voltage measurement function (VMF)(s) and current measurement function
(CMF)(s) in the power circuit shall ensure that all active and reactive energy taken from and
returned to the CL is measured.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.
Devices consuming small quantities of energy (e.g. high impedance voltage
monitoring/detection devices, insulators, etc.) are not considered significant and their
consumption needs not be measured by the EMS.

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4.2.4.2 Characteristics of traction supply system
The ratings of the EMS voltage and current measuring inputs shall be selected in accordance
with IEC 62888-2 taking into account the intended traction energy supply system and traction
unit rated current.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.
4.2.5 Data handling
4.2.5.1 Traction supply system change
An EMS (one or multiple) shall cover all traction supply system types that the traction unit can
operate on.
If an EMS is used for more than one traction supply system, it shall continue to function
correctly when changing between systems and log each change of traction supply system.
Changes between 600 V and 750 V DC traction supply systems do not need to be logged.
NOTE This can be achieved directly by the EMS or by input signals from the traction unit.
If voltage detection is used to detect traction supply system change, overvoltages above
U , in accordance with IEC 60850, and voltage drops below U could cause a detection
max2 min2
of a system change.
In changing the traction supply system, the EMS shall measure energy consumption within the
time listed in Table 3.
Table 3 – Traction supply system change classes
Traction supply system Maximum time
change classes
s
TSC-A 1
TSC-B 2
TSC-X Agreed between the involved parties

Unless otherwise specified, the requirements of category TSC-A apply.
4.2.5.2 Consumption Point Identification (CPID)
A consumption point is identified using a Country Code (CC), a Vehicle Keeper Marking
(VKM), a Vehicle Identification Number (VIN) and the EMF-ID (n).
• Country Code (CC): coding of the countries in which the vehicles are registered,
consisting of 2 characters as defined by ISO 3166-1 alpha-2;
• Vehicle Keeper Marking (VKM): an alphabetic code, consisting of 2 to 5 characters
• Vehicle Identification Number (VIN): the number defined by Intergovernmental
organisation for international carriage by rail (OTIF) is the unique identifier of the
vehicle/consist on which one or more EMS are installed and is composed of 12 numerical
digits;
• n is the number identifying the EMF installed in the consist.
NOTE 1 For European countries, 13 digit number (numeric value without dividers or decimals) is used based on a
VIN from the traction unit plus one additional digit.
NOTE 2 Where a traction unit has more than one EMS, the additional digits are used to uniquely identify each
EMS within the traction unit.
NOTE 3 The EMS can carry a fictitious CPID until such time as the EMS is commissioned into commercial use.
The process of assigning the correct CPID to a specific EMS needed when bringing it into commercial use is out of
the scope of this document.
The CPID shall be stored in non-volatile memory of the EMS. Security procedures shall be
implemented to prevent unauthorised changes to the CPID for EMS level 1.
Identification number (ID) of each EMS shall be assigned. Reference method between CPID
and ID of EMS shall be provided. Access to the EMSs of distributed measurement is limited to
the authorised maintenance persons. Personnel control may be regarded as a security
procedure.
4.2.6 Reliability, Availability, Maintainability and Safety (RAMS)
4.2.6.1 Reliability
Reliability requirements shall be in accordance with IEC 60571:2012, 6.1.1. Reliability figures
and calculation methods are a matter of agreement between the supplier and purchaser.
For level 2 and level 3, if the measurement is carried out temporarily, reliability of long
operation may not be required. Reliability requirements and methods may be agreed between
the involved parties, in this case IEC 60571:2012 may not be applicable.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.
4.2.6.2 Availability
Calculation methods and availability figures shall be agreed between the supplier and
purchaser.
4.2.6.3 Maintainability
Maintainability requirements shall be in accordance with IEC 60571:2012, 6.3, 6.4 and 6.5.
Further requirements, if any, shall be agreed between the supplier and purchaser.
For level 2 and level 3, if the measurement is carried out temporarily, regular maintenance
may not be required. Maintainability requirements and methods may be agreed by the
involved parties, in this case IEC 60571:2012 may not be applicable.
4.2.6.4 Safety
The EMS shall be designed, manufactured and installed on board the traction unit in such a
way that it is safe in normal use and under normal conditions, in particular to ensure;
• personal safety against electric shock in accordance with IEC 61991,
• personal safety against effects of excessive temperature in accordance with ISO 13732-1,
• protection against spread of fire shall be agreed between the involved parties at the tender
time.
NOTE 1 For European countries, guidelines can be found in EN 50155, EN 45545-2 and EN 45545-5.
NOTE 2 When considering personal safety (electric shock risk), CL failure is a credible failure condition. This can
pose a risk if a live part of the CL comes into direct contact with an exposed part of the EMS, or an exposed device
connected directly to the EMS (e.g. roof mounted devices containing VMF, CMF or antenna).

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4.3 Device level requirements
4.3.1 Marking and availability of essential data
4.3.1.1 Identification and marking
The EMS function shall be clearly identified.
In case of dedicated devices, each device of the EMS shall be permanently and clearly
marked, internally or externally, with the following information. If the marking is internal it shall
be visible from the outside of the device.
Marking shall include:
a) the manufacturer’s name or trade mark;
b) the designation of equipment type;
c) the serial number and date of manufacturing.
It is permitted to integrate the date of manufacturing into the serial number.
The device marking may contain other additional information.
In case of EMS as a function included in the function of traction equipment or auxiliary
equipment, marking of equipment type is not necessary.
4.3.1.2 Availability of essential information
The following information shall be available in a format (e.g. hardcopy or electronic) agreed
between supplier and purchaser:
a) data identifying all devices in the EMS and the EMS configuration;
b) all information necessary to specify the characteristics and control the behaviour of each
device of the EMS;
c) any special installation requirements necessary to ensure safe and correct operation (e.g.
any requirements related to personal safety, installation environmental constraints to
ensure correct operation, etc.).
4.3.2 Interfaces
4.3.2.1 General
Any interfaces associated with the EMS shall comply with the following requirements:
• the use of any interface shall not degrade the performance of the EMS;
• the normal operation of the EMS shall be secured against unintentional influence or
unintentional changes caused by use of any interface;
• the choice of communication shall be in accordance with IEC 62888-4 and shall be agreed
between the involved parties.
Interfaces may be used for more than one purpose.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.

4.3.2.2 Mandatory interfaces
4.3.2.2.1 Maintenance and service interfaces
The EMS shall have the capability to be interrogated locally by qualified persons on board the
traction unit using appropriate equipment (e.g. laptop computer, display) for audit, recovery of
data, maintenance, etc.
This interface may be provided on one or more devices of the EMS.
Access to data via this interface shall be protected in order to prevent access and
modifications by non-authorised personnel. Examples of suitable protection include the use of
passwords, cryptography, etc.
4.3.2.2.2 Operational interfaces
Each function shall have input and output interfaces.
These interfaces link the individual functions to form the EMS.
4.3.2.2.3 Test interfaces
Each function of the EMS shall be provided with input and output test interfaces. The input
interface shall allow injection of input signals and the output interface shall allow
measurement and monitoring. Interfaces for testing shall be clearly identified and designated
as ‘input’ and / or ‘output’ test interfaces.
Any signals injected for testing shall not cause any changes to existing CEMD.
If signals injected for testing generate or influence new CEMD, this data should not be
presented as valid CEMD.
If the operational interface of a function is accessible and can be used as a test interface,
then an additional test interface is not required.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.
In case of EMS as a function included in the function of traction equipment or auxiliary
equipment, internal test functions may be included in order to perform self-testing. In case
self-testing is included, the test interfaces may be omitted.
4.3.2.3 Access security
This subclause covers requirements for access to any function of the EMS from an external
source.
Any request for access to data, software or system parameters that may affect the production
and storage of CEMD and CEMD-related data shall go through an authorisation procedure
before access is granted.
NOTE Requests for access can be either from a remote location or on-site using portable equipment or human
machine interface device.
Access to other data, software or system parameters can have different access rights as long
as this has no influence for the production and storage of CEMD and CEMD-related data.
All requests for access and all changes shall be automatically logged within the EMS.
Requirements applicable to level 2 and level 3 are specified in IEC 62888-6.

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Logging of a read-only access is not mandatory.
Access rights shall be agreed between the supplier and purchaser.
It is advisable to be able to have more than one level of access rights, e.g. user and
administrator. Some types of access need no authorisation procedure.
4.3.3 Data processing and transfer
The EMS can also process and transfer other data or datasets associated with other aspects
of the EMS. The processing of this data shall be a secondary priority for the EMS and shall
not affect the CEMD. Flow and processing of data associated with CEMD shall take priority.
4.3.4 Software
4.3.4.1 General
Software shall be designed, tested and documented according to IEC 60571:2012.
4.3.4.2 Identification of functions implemented in software
Any functions implemented in software shall be unambiguously identified and their operation
suitably documented by the supplier.
4.3.4.3 Identification and protection of software
Software version shall be easily identifiable. The software version used for the production and
storage of the CEMD in each device of a given equipment type shall be identical to the
version used for conformance test.
The software shall be protected against any accidental or intentional changes. Any changes
or attempts to make a change shall be recorded. Any corruption of the software used for the
production an
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