WG 20 - TC 85/WG 20

IEC TS 62586-3:2025 Describes a procedure used for maintenance tests of individual power quality instruments. Users of these instruments need to ensure the conformity of the individual power quality instrument for stationary use with the requirements of IEC 62586‑1. This is achieved by periodic maintenance tests as defined in this document.

IEC 63297:2025 provides a classification of NILM sensing devices for use in NILM systems, according to the state of the art of NILM technologies.

IEC 60688:2024 applies to transducers (TRD) with electrical inputs and outputs for making measurements of AC or DC electrical quantities. The output signal can be in the form of an analogue or digital signal.
This document applies to measuring transducers used for converting electrical quantities such as:
– current,
– voltage,
– active power,
– reactive power,
– power factor,
– phase angle,
– frequency,
– harmonics or total harmonic distortion,
– apparent power, and
– DC power
to an output signal.
This document applies
a) if the fundamental frequency of the input(s) lies between 0 Hz and 1 500 Hz,
b) to the electrical measuring transducer if it is part of a system for the measurement of an electrical or non-electrical quantity,
c) to transducers for use in a variety of applications such as telemetry and process control and in one of a number of defined environments.
This document is not applicable for:
– instrument transformers that comply with IEC 61869 (all parts),
– transmitters for use in an industrial process application that comply with IEC 60770 (all parts),
– power metering and monitoring devices (PMD) that comply with IEC 61557-12,
– meters that comply with the IEC 62053 series,
– handheld sensors,
– residual current monitoring devices (RCMs) that comply with IEC 62020-1,
– residual current detecting devices (RDC-DD) that comply with IEC 62955,
– in-cable control and protection devices (IC-CPDs) that comply with IEC 62752,
– modular residual current devices (MRCDs) that comply with IEC 60947 2:2016/AMD1:2019, Annex M.
Within the measuring range, the output signal is a function of the measurand. An auxiliary supply can be required.
This document is intended:
– to specify the terminology and definitions relating to transducers whose main application is in industry,
– to unify the test methods used in evaluating transducer performance,
– to specify accuracy limits and output values for transducers.
IEC 60688:2024 cancels and replaces the fourth edition published in 2021. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) updating normative references;
b) updating definitions;
c) updating structure;
d) adding DC power measurement.

IEC 62974-1:2024 specifies product and performance requirements for devices that fall under the heading of "monitoring and measuring systems used for data collection, aggregation and analysis", for industrial, commercial, and similar use rated below or equal to 1 kV AC and 1,5 kV DC.
These devices are fixed and are intended to be used indoors as panel-mounted devices, or as modular devices fixed on a DIN rail, or as housing devices fixed on a DIN rail, or as devices fixed by other means inside a cabinet.
These devices are used to upload or download information (energy measured on loads, power metering and monitoring data, temperature information, etc.), mainly for energy efficiency purposes. These devices are known as energy servers (ESE), energy data loggers (EDL), data gateways (DGW) and I/O data concentrators (IODC) and are grouped together under the family name of Data Management Devices (DMD).
This document does not cover:
• devices used only in the consumer market (living quarters) or household;
• devices used in the smart metering infrastructure (e.g. smart meters);
• devices used in the smart grid infrastructure;
• devices used as IT servers in the information technology business;
• power metering and monitoring devices (PMD);
• I/O data concentrators already covered by a specific product standard;
• communication protocols and interoperability;
• power quality instruments (PQI);
• software used for the data collection and analysis of the power quality for the supply side.
IEC 62974-1:2024 cancels and replaces the first edition published in 2017. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the performance criteria have been reviewed;
b) EMC and safety requirements have been improved;
c) mechanical requirements have been clarified and amended.

IEC TS 63191:2023 specifies recommendations about power quality measurement and assessment within installations.
This document outlines the various phases needed for the establishment of a demand-side power quality measurement plan for buildings and industry installations.
Such a power quality measurement plan will enable the optimization of the energy availability and efficiency, improve the assets lifetime and facilitate the resolutions of power quality problems. A power quality measurement plan encompasses the following phases:
• definition of the context, objectives and constraints;
• assessment of the initial power quality situation;
• definition of an action plan for the improvement of the power quality situation;
• implementation of the power quality measuring system;
• exploitation of the measurement system for the improvement of the power quality situation;
• maintenance of the measurement system.
This document will also help facility managers tailor their measurement plan to the specific needs of the electrical system under their control. It addresses all the disturbances present in such networks, but does not cover the disturbances present in public electrical distribution networks (supply side) as they are governed by specific documents such as EN 50160 and IEC TS 62749.
IEC TS 63191:2023 cancels and replaces IEC TR 63191, published in 2018. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) a new informative Annex A describing a tool to report the ability to assess the power quality of an electrical installation.

IEC TS 63383:2022 deals with cybersecurity related to measuring devices (PMD according to IEC 61557-12 and PQI according to IEC 62586-1) and devices for data collection (devices according to IEC 62974-1) that are intended to be installed in restricted access areas.
This document deals with cybersecurity aspects (e.g. device hardening or device resilience) of device(s) used for power metering and monitoring, power quality monitoring, data collection and analysis, but does not cover requirements for organisational cybersecurity (e.g. end-user security policy).
This document is a first attempt to develop awareness by manufacturers and other relevant stakeholders about cybersecurity aspects and provide basic guidance for achieving the appropriate security mitigation against vulnerabilities to security threats:
– in coherence with device/system approaches described in relevant standards such as IEC 62443 (all parts) and ISO/IEC 27001,
– based on generic system use-cases.
This document does not cover billing meters covered by the IEC 62053-2x set of standards.

IEC 60688:2021 applies to transducers with electrical inputs and outputs for making measurements of AC or DC electrical quantities. The output signal can be in the form of an analogue direct current, an analog direct voltage or in digital form.
This document applies to measuring transducers used for converting electrical quantities such as
– current,
– voltage,
– active power,
– reactive power,
– power factor,
– phase angle,
– frequency,
– harmonics or total harmonic distortion, and
– apparent power
to an output signal.
This document is not applicable for
– instrument transformers that complies with IEC 61869 (all parts),
– transmitters for use in industrial process application that complies with IEC 60770 (all parts), and
– performance measuring and monitoring devices (PMD) that comply with IEC 61557 12:2018.
Within the measuring range, the output signal is a function of the measurand. An auxiliary supply can be needed.
This document applies
a) if the nominal frequency of the input(s) lies between 0 Hz and 1 500 Hz,
b) to the electrical measuring transducer if it is part of a system for the measurement of a non-electrical quantity, and if it otherwise falls within the scope of this document, and
c) to transducers for use in a variety of applications such as telemetry and process control and in one of a number of defined environments.
This document is intended:
– to specify the terminology and definitions relating to transducers whose main application is in industry,
– to unify the test methods used in evaluating transducer performance, and
– to specify accuracy limits and output values for transducers.
IEC 60688:2021 cancels and replaces the third edition published in 2012. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) updating normative references;
b) additional requirements for specific transducers used for LV monitoring applications;
c) creation of interface coding to ease selection by the end-user.

IEC 62586-2:2017 specifies functional tests and uncertainty requirements for instruments whose functions include measuring, recording, and possibly monitoring power quality parameters in power supply systems, and whose measuring methods (class A or class S) are defined in IEC 61000-4-30.
This document applies to power quality instruments complying with IEC 62586-1.
This document can also be referred to by other product standards (e.g. digital fault recorders, revenue meters, MV or HV protection relays) specifying devices embedding class A or class S power quality functions according to IEC 61000-4-30.
These requirements are applicable in single-, dual- (split phase) and 3-phase AC power supply systems at 50 Hz or 60 Hz.
This second edition cancels and replaces the first edition published in 2013. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- test procedures for RVC and current have been added;
- mistakes have been fixed.
The contents of the corrigendum of June 2018 have been included in this copy.

The contents of the corrigendum 1 (2022-09) have been included in this copy.

IEC TS 63297:2021 is an attempt to provide classification of NILM sensing devices for use in NILM systems, according to the state of the art of NILM technologies.
The classification of NILM analytics and NILM systems, as well as performance indicators for NILM systems, can be considered in the future.
NILM systems produce estimated disaggregation into energy usages. When accurate measurement and analysis of energy consumption and/or other electrical parameters is needed (e.g. for monitoring the electrical installation), systems based on standardized measuring devices (e.g. PMD, PQI or meters) are used.

IEC 61557-12:2018 specifies requirements for power metering and monitoring devices (PMD) that measure and monitor the electrical quantities within electrical distribution systems, and optionally other external signals. These requirements also define the performance in single- and three-phase AC or DC systems having rated voltages up to 1 000 V AC or up to 1 500 V DC. These devices are fixed or portable. They are intended to be used indoors and/or outdoors. Power metering and monitoring devices (PMD), as defined in this document, give additional safety information, which aids the verification of the installation and enhances the performance of the distribution systems. The power metering and monitoring devices (PMD) for electrical parameters described in this document are used for general industrial and commercial applications. This document does not address functional safety and cyber security aspects. This document is not applicable for:
– electricity metering equipment that complies with IEC 62053-21, IEC 62053-22, IEC 62053-23 and IEC 62053-24. Nevertheless, uncertainties defined in this document for active and reactive energy measurement are derived from those defined in IEC 62053 (all parts);
– the measurement and monitoring of electrical parameters defined in IEC 61557-2 to IEC 61557-9 and IEC 61557-13 or in IEC 62020;
– power quality instrument (PQI) according IEC 62586 (all parts);
– devices covered by IEC 60051 (all parts) (direct acting analogue electrical measuring instrument). IEC 61557-12:2018 cancels and replaces the first edition published in 2007. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) PMD-A has been withdrawn due the fact these devices are now mainly covered by the IEC 62586 series of standards.
b) Three categories of PMD have been created with a list of minimum required functions for each category.
c) Added a new Annex A explaining the different applications linked to the relevant standards and devices, and another new Annex C about the power factor conventions.
The contents of the corrigendum 1 (2022-09) have been included in this copy.

IEC 62586-1:2017 specifies product and performance requirements for instruments whose functions include measuring, recording and possibly monitoring power quality parameters in power supply systems, and whose measuring methods (class A or class S) are defined in IEC 61000-4-30.
These requirements are applicable in single, dual- (split phase) and 3-phase AC power supply systems at 50 Hz or 60 Hz.
This edition includes the following significant technical changes with respect to the previous edition:
a) integration of the new measurement functions of IEC 61000-4-30:2015 (e.g. RVC and current functions);
b) integration of the new requirements of IEC/TS 61000-6-5:2015, update of definitions of environment G and H, update of applicable EMC performance criteria;
c) correction of minor mistakes, improvement in specification.
It has the status of a basic EMC publication in accordance with IEC Guide 107.

IEC 62974-1:2017 specifies product and performance requirements for devices that fall under the heading of “monitoring and measuring systems used for data collection, gathering and analysis”, for industrial, commercial and similar use rated below or equal to 1 kV AC and 1,5 kV DC.
These devices are fixed and are intended to be used indoors as panel-mounted devices, or as modular devices fixed on a DIN rail, or as housing devices fixed on a DIN rail, or as devices fixed by other means inside a cabinet.
These devices are used to upload or download information (energy measured on loads, power metering and monitoring data, temperature information…), mainly for energy efficiency purposes. These devices are known as energy servers, energy data loggers, data gateways and I/O data concentrators.

IEC 62586-1:2013 specifies product and performance requirements for instruments whose functions include measuring, recording and possibly monitoring power quality parameters in power supply systems, and whose measuring methods (class A or class S) are defined in IEC 61000-4-30. These requirements are applicable in single, dual- (split phase) and 3-phase a.c. power supply systems at 50 Hz or 60 Hz. These instruments can be used in the generation, transmission and distribution of electricity, for example inside a power station, substation or a distributed generator connection and at the interface point between the installation and the network, e.g. in order to check the compliance of the connection agreement between a network operator and the customer. These instruments are fixed-installed or portable. They are intended to be used indoors and/or outdoors. Devices such as digital fault recorders, energy/power meters, protection relays or circuit breakers may include power quality functions defined in 61000-4-30 class A or class S. If such devices are specified according to this standard, then this standard fully applies and applies in addition to the relevant product standard. This standard does not replace the relevant product standard.

IEC 62586-2:2013 specifies functional tests and uncertainty requirements for instruments whose functions include measuring, recording, and possibly monitoring power quality parameters in power supply systems, and whose measuring methods (class A or class S) are defined in IEC 61000-4-30. This standard applies to power quality instruments complying with IEC 62586-1. This standard may also be referred to by other product standards (e.g. digital fault recorders, revenue meters, MV or HV protection relays) specifying devices embedding class A or class S power quality functions according to IEC 61000-4-30. These requirements are applicable in single, dual- (split phase) and 3-phase a.c. power supply systems at 50 Hz or 60 Hz. The contents of the corrigendum of November 2014 have been included in this copy.

IEC 60688:2012 applies to transducers with electrical inputs and outputs for making measurements of a.c. or d.c. electrical quantities. This International Standard is intended to specify the terminology and definitions relating to transducers whose main application are in industry; to unify the test methods used in evaluating transducer performance; and to specify accuracy limits and output values for transducers. The output signal may be in the form of an analogue direct current, an analogue direct voltage or in digital form. In this case, that part of the transducer utilized for communication purposes will need to be compatible with the external system. This standard applies to measuring transducers used for converting electrical quantities such as current, voltage, active power, reactive power, power factor, phase angle, frequency, harmonics or total harmonic distortion, and apparent power to an output signal. This standard is not applicable for instrument transformers that comply with IEC 60044 series; transmitters for use in industrial process applications that comply with the IEC 60770 series; performance measuring and monitoring devices (PMD) that comply with IEC 61557-12. The contents of the corrigendum of December 2013 have been included in this copy.

Specifies requirements for combined performance measuring and monitoring devices that measure and monitor the electrical parameters within electrical distribution systems. These requirements also define the performance, in single and three-phase a.c. or d.c. systems having rated voltages up to 1 000 V a.c. or up to 1 500 V d.c. These devices are fixed installed or portable. They are intended to be used indoors and/or outdoors. This standard is not applicable for: - electricity metering equipment that complies with IEC 62053-21, IEC 62053-22 and IEC 62053-23. Nevertheless, uncertainties defined in this standard for active and reactive energy measurement are derived from those defined in the IEC 62053 standards series. - simple remote relays or simple monitoring relays. This standard is intended to be used in conjunction with IEC 61557-1 (unless otherwise specified), which specifies the general requirements for measuring and monitoring equipment, as required in IEC 60364-6. The standard does not include the measurement and monitoring of electrical parameters defined in Parts 2 to 9 of IEC 61557 or in IEC 62020. Combined performance measuring and monitoring devices (PMD), as defined in this standard, give additional safety information, which aids the verification of the installation and enhances the performance of the distribution systems. For instance, those devices help to check if the level of harmonics is still compliant with the wiring systems as required in IEC 60364-5-52. The combined performance measuring and monitoring devices (PMD) for electrical parameters described in this standard are used for general industrial and commercial applications. A PMD-A is a specific PMD complying with requirements of IEC 61000-4-30 class A, which may be used in "power quality assessment" applications.