By sion932 
The International Electrotechnical Commission (IEC) has long been at the forefront of establishing global standards for electrical and electronic technologies, ensuring interoperability, safety, and performance across industries. Among its extensive portfolio, the IEC 62053 series focuses on electricity metering equipment, with Part 23 specifically addressing static meters for reactive energy measurement. The 2020 edition of IEC 62053-23 (IEC 62053-23:2020), a technical revision of the 2003 first edition and its 2016 amendment, introduces refined requirements and scope definitions that significantly impact the design, testing, and application of reactive energy meters worldwide. This article delves into the core specifications of IEC 62053-23:2020, highlights key changes from previous versions, and discusses its implications for manufacturers, utilities, and the broader electrical industry.
1. Scope and Application Boundaries
IEC 62053-23:2020 is specifically tailored to static var-hour meters of accuracy classes 2 and 3, designed for measuring alternating current (AC) reactive energy in 50 Hz or 60 Hz electrical networks. A critical scope limitation is that the standard applies exclusively to type tests of such meters, focusing on validating design conformance rather than individual product inspection. For practical measurement purposes, the standard adopts a conventional definition of reactive energy, restricted to sinusoidal currents and voltages containing only the fundamental frequency—a simplification that aligns with typical grid operating conditions while ensuring measurement consistency.
The standard explicitly covers electricity metering equipment designed to meet the following criteria: (1) Measuring and controlling electrical energy in mains networks with a voltage up to 1000 V AC (line-to-neutral derived from nominal voltages); (2) Encompassing all functional elements, including add-on modules, within a single meter case (excluding indicating displays); (3) Operating with integrated, detached, or no indicating displays; (4) Being installed in specified matching sockets or racks; and (5) Optionally providing additional functions beyond reactive energy measurement. Notably, meters intended for use with low-power instrument transformers (LPITs, as defined in the IEC 61869 series) can only be considered compliant if tested together with their LPITs and meet the requirements for directly connected meters.
Conversely, IEC 62053-23:2020 excludes several categories of equipment, including meters with a line-to-neutral voltage exceeding 1000 V AC, LPIT-connected meters tested without their transformers, distributed metering systems with physically remote devices (excluding LPITs), portable meters, and meters used in rolling stock, vehicles, ships, or airplanes. Additionally, laboratory/test equipment, reference standard meters, data interfaces to meter registers, installation sockets/racks, and any additional functions beyond energy measurement are outside the standard’s scope. Importantly, the standard does not address measures for detecting or preventing meter tampering, leaving such requirements to specialized standards or regulatory frameworks.
2. Core Technical Requirements
At the heart of IEC 62053-23:2020 are the technical requirements governing meter performance, with a focus on accuracy and reliability. The standard defines specific criteria for starting current and minimum current, which are critical for ensuring accurate measurement even at low load conditions—an essential feature for utilities to avoid undercounting reactive energy consumption. Table 1 and Table 2 of the standard outline these current thresholds, with variations based on meter type (single-phase or polyphase) and load balance. For accuracy, Table 3 specifies acceptable percentage error limits for class 2 and class 3 meters, differentiating between single-phase and polyphase meters with balanced loads. Class 2 meters, intended for billing applications, require tighter error margins, while class 3 meters are suitable for power factor correction and general monitoring purposes.
Another key requirement is the stability of meter performance under varying operating conditions. Table 4 of the standard defines acceptable limits of variation in percentage error due to influence quantities—environmental and electrical factors such as temperature fluctuations, voltage variations, and frequency deviations. These requirements ensure that meters maintain their specified accuracy across the range of conditions encountered in typical grid installations. While the standard does not include safety requirements (relocated to IEC 62052-31:2015), compliance with IEC 62053-23:2020 is often paired with safety certifications to meet comprehensive regulatory requirements.
3. Significant Changes from the 2003 Edition
As a technical revision, IEC 62053-23:2020 introduces several impactful changes from the 2003 first edition and its 2016 amendment. The most notable changes are summarized in Annex B of the standard and include the following: (a) Removal of all meter safety requirements, which are now exclusively covered in IEC 62052-31:2015. This restructuring enhances standardization efficiency by centralizing safety requirements in a dedicated document, allowing IEC 62053-23:2020 to focus solely on performance and type test requirements. (b) Replacement of the current symbol Ib with In when referencing directly connected meters. This change aligns the standard with modern electrical terminology, reducing ambiguity in technical documentation and manufacturing specifications. (c) Consolidation of general requirements and test methods into a single foundational standard. Previously scattered across IEC 62053-21:2003, 62053-22:2003, 62053-23:2003, and 62053-24:2003, these general provisions are now unified in IEC 62052-11:2020. As a result, IEC 62053-23:2020 and its companion parts (21, 22, 24) now contain only accuracy class-specific requirements, streamlining compliance and reducing redundancy.
4. Industry Implications and Compliance Considerations
IEC 62053-23:2020 plays a pivotal role in ensuring the reliability and interoperability of reactive energy meters globally. For manufacturers, compliance with the standard requires re-evaluating meter designs to align with the revised requirements, particularly the exclusion of safety provisions and the adoption of new terminology. Manufacturers of LPIT-compatible meters must also adjust their testing protocols to ensure meters and transformers are tested together, adding a layer of complexity but improving measurement accuracy in real-world applications. Utilities and grid operators benefit from the standard’s refined accuracy requirements, as compliant meters enable more precise billing for reactive energy and better management of power factor—critical for grid efficiency and reducing energy waste.
Compliance with IEC 62053-23:2020 is not only a technical necessity but also a market access requirement in many regions. For example, the European Union’s Electromagnetic Compatibility (EMC) Directive (2014/30/EU) references IEC standards for electrical metering equipment, making compliance a prerequisite for CE marking and market entry. Additionally, national standards bodies, such as Estonia’s EVS and France’s AFNOR, have adopted IEC 62053-23:2020 as national standards (e.g., EVS-EN IEC 62053-23:2021, NF EN IEC 62053-23), further emphasizing its global relevance.
It is important to note that while IEC 62053-23:2020 does not cover additional meter functions (e.g., power quality measurement, load control, data communication), modern meters often integrate these features. Manufacturers must ensure that such additional functions comply with relevant standards (e.g., IEC 61557-12 for power metering and monitoring devices) while meeting the reactive energy measurement requirements of IEC 62053-23:2020. For billing applications, meters with additional functions must also demonstrate compliance with IEC 62053-23:2020 to be legally recognized for reactive energy billing.
5. Conclusion
IEC 62053-23:2020 represents a significant advancement in the standardization of static reactive energy meters, refining scope boundaries, centralizing general requirements, and aligning with modern electrical terminology. By focusing on accuracy class-specific requirements and type test protocols, the standard ensures that class 2 and 3 reactive energy meters deliver reliable performance across typical grid conditions. For manufacturers, utilities, and regulatory bodies, compliance with IEC 62053-23:2020 is essential for market access, billing accuracy, and grid efficiency. As the electrical industry continues to evolve toward smarter grids and more efficient energy management, the role of standards like IEC 62053-23:2020 will remain critical in fostering global interoperability and driving sustainable energy practices.
References
[1] IEC. (2020). IEC 62053-23:2020 Electricity metering equipment – Particular requirements – Part 23: Static meters for reactive energy (classes 2 and 3). Geneva: International Electrotechnical Commission.
[2] EVS. (2021). EVS-EN IEC 62053-23:2021 Electricity metering equipment – Particular requirements – Part 23: Static meters for reactive energy (classes 2 and 3) (IEC 62053-23:2020).
[3] HK LEE HING INDUSTRY CO., LIMITED. (2025). IEC 62053-23: Electricity Metering Equipment (AC) – Particular Requirements – Static Meters for Reactive Energy (Classes 2 and 3).