By sion932 
The International Electrotechnical Commission (IEC) has long been committed to formulating and publishing international standards for electrical, electronic, and related technologies, ensuring the accuracy, consistency, and safety of electrical equipment globally. Among them, the IEC 62053 series standards focus on electricity metering equipment, and IEC 62053-24:2020, as the second edition of this series’ Part 24, plays a crucial guiding role in the field of static meters for fundamental component reactive energy measurement. This article elaborates on the core content, technical revisions, and practical application value of IEC 62053-24:2020, aiming to provide technical reference for relevant practitioners in the industry.
1. Scope and Core Definition of IEC 62053-24:2020
IEC 62053-24:2020 is specifically applicable to static var-hour meters of accuracy classes 0.5S, 1S, 1, 2, and 3, which are designed for measuring alternating current electrical reactive energy in 50 Hz or 60 Hz power networks. It should be emphasized that this standard only applies to type tests of such meters, providing a unified evaluation basis for the type approval of reactive energy metering equipment.
A key definition in the standard is the conventional definition of reactive energy: reactive power and energy are calculated solely from the fundamental frequency components of currents and voltages, excluding harmonic components. This definition ensures the consistency and accuracy of reactive energy metering under standard working conditions, avoiding measurement deviations caused by harmonic interference.
In terms of applicable equipment characteristics, the standard specifies that the covered electricity metering equipment should meet the following requirements: First, it is used to measure and control electrical energy in mains networks with a voltage up to 1000 V AC. Second, all functional elements, including add-on modules, are enclosed in or form a single meter case, except for indicating displays. Third, it can operate with integrated, detached, or no indicating displays. Fourth, it is installed in a specified matching socket or rack. Additionally, the equipment may optionally provide additional functions beyond reactive energy measurement.
It should be noted that the standard has clear exclusion scopes, such as meters where the line-to-neutral voltage derived from nominal voltages exceeds 1000 V AC, meters intended for connection with low-power instrument transformers (LPITs as defined in the IEC 61869 series) when tested without such transformers, portable meters, meters used in rolling stock, vehicles, ships, and airplanes, as well as laboratory test equipment and reference standard meters. Moreover, the standard does not cover measures for detecting and preventing tampering attempts that may compromise meter performance, nor does it regulate data interfaces of meter registers or installation sockets/racks.
2. Key Technical Requirements and Test Methods
IEC 62053-24:2020 specifies strict technical requirements for static reactive energy meters, covering accuracy, starting current, minimum current, and anti-interference performance, among other aspects, and provides corresponding test methods to ensure that the equipment meets the operational requirements.
In terms of accuracy requirements, the standard defines acceptable percentage error limits for single-phase meters and three-phase meters under balanced or single-phase loads, which vary according to different accuracy classes and load conditions. For example, under reference conditions, the error limits of Class 0.5S meters are stricter than those of Class 1 meters. Additionally, the standard also specifies the allowable variation range of percentage errors caused by factors such as voltage, frequency, and temperature changes, ensuring the stability of meter performance under different working environments.
Regarding starting and minimum current requirements, the standard clearly stipulates the minimum current values that meters of different accuracy classes need to measure, as well as the starting current thresholds. This ensures that the meters can accurately measure reactive energy even under light load conditions, avoiding energy loss caused by ineffective measurement of small currents.
For meters used with LPITs, the standard has special requirements: such meters and their matching LPITs must be tested together and meet the requirements for directly connected meters to be deemed compliant. This avoids measurement errors caused by mismatched transformers and ensures the overall accuracy of the metering system.
In addition, the standard also includes test methods for harmonics. Although reactive energy is calculated based on fundamental components, the standard requires testing the accuracy of meters under non-sinusoidal conditions (such as fifth harmonic injection) to verify the anti-interference ability of meters against harmonic components in actual power grids.
3. Significant Technical Revisions Compared with the Previous Edition
IEC 62053-24:2020 cancels and replaces the first edition published in 2014 and its Amendment 1:2016, and constitutes a technical revision. The specific revision content is detailed in Annex E of the standard, mainly involving the optimization of technical requirements and the improvement of test methods, aiming to adapt to the development of power grid technology and the increasing demand for metering accuracy.
One of the important revisions is the refinement of accuracy requirements. With the continuous improvement of power grid operation efficiency requirements, the new edition has stricter error limits for high-accuracy class meters (such as Class 0.5S and 1S), ensuring more accurate reactive energy measurement. Additionally, the revision optimizes the test conditions for non-sinusoidal environments, making the test methods more in line with the actual operating conditions of modern power grids, where harmonic pollution is increasingly prominent.
Another key revision is the supplement and improvement of the technical requirements for LPIT-matched meters. With the widespread application of LPITs in power metering systems, the new edition clarifies the joint test requirements for meters and LPITs, avoiding potential measurement risks caused by unclear regulations in the previous edition. This revision enhances the applicability of the standard in complex metering systems.
4. Application of IEC 62053-24:2020 in Industry Practice
As an international standard for fundamental component reactive energy metering, IEC 62053-24:2020 has been widely adopted in the design, production, and certification of electrical metering equipment globally, providing important technical support for energy management and cost allocation in various fields such as buildings, industry, and data centers.
In commercial building energy management, many manufacturers have launched smart meters that comply with IEC 62053-24:2020. For example, Schneider Electric’s EasyLogic PM2000 power meter achieves Class 1.0 accuracy for reactive energy in accordance with the standard. This meter not only ensures the accuracy of reactive energy measurement but also provides customizable rate counters, enabling users to measure indicators such as kg CO₂/kWh, facilitating energy cost management and carbon emission monitoring. Meanwhile, its good compatibility allows for simple integration with existing building management systems, helping users quickly identify power quality problems and optimize energy efficiency.
In the industrial field, the standard provides a unified technical basis for the selection and application of reactive energy meters. Enterprises can use meters that comply with IEC 62053-24:2020 to accurately measure reactive energy consumption in production processes, optimize reactive power compensation, reduce energy waste, and lower operating costs. Additionally, in sub-billing and cost allocation scenarios, the accurate measurement results guaranteed by the standard ensure the fairness and reasonableness of energy cost sharing among different departments or tenants.
In terms of standardization and certification, IEC 62053-24:2020 has become an important basis for the certification of static reactive energy meters in various countries. Manufacturers need to design and produce products in accordance with the standard’s requirements and pass corresponding type tests to obtain market access qualifications. This promotes the improvement of the overall quality level of the global electrical metering equipment industry and facilitates international trade and technical exchanges of products.
IEC 62053-24:2020, as an important international standard for static meters for fundamental component reactive energy measurement, clearly defines the scope of application, technical requirements, and test methods of related equipment, and has made targeted technical revisions based on the development of the industry. The implementation of this standard not only ensures the accuracy and consistency of reactive energy metering but also provides strong support for energy management optimization, cost control, and quality improvement of electrical metering equipment in various fields. With the continuous development of the global power industry and the increasing emphasis on energy conservation and emission reduction, the application value of IEC 62053-24:2020 will be further highlighted. In the future, relevant enterprises and institutions should continue to follow the requirements of the standard, promote technological innovation and product upgrading of reactive energy metering equipment, and contribute to the safe, efficient, and low-carbon operation of the global power grid.