Overview
IEC 60050-112:2010/AMD2:2020 is Amendment 2 to Part 112 of the International Electrotechnical Vocabulary (IEV), focusing on quantities and units within the electrotechnical field. This amendment updates and refines standardized definitions of the International System of Units (SI units) related to fundamental physical quantities, ensuring consistency and precision in technical terminology used globally.
Managed by the International Electrotechnical Commission (IEC), this amendment supports standardized usage in documentation, engineering, science, and education. It harmonizes unit definitions with the latest SI Brochure (9th edition, 2019) and aligns terminology with international measurement standards crucial for electrotechnical applications.
Key Topics
This amendment specifically revises the IEC IEV entries for the seven SI base units and their definitions, clarifying foundational physical quantities:
- Second (s): Defined by the fixed numerical value of the caesium-133 atom’s hyperfine transition frequency, providing the precise unit of time based on atomic properties.
- Metre (m): Defined by the distance light travels in vacuum during a duration of 1/299,792,458 of a second.
- Kilogram (kg): Defined through Planck's constant, providing a mass reference based on fundamental physical constants instead of a physical artifact.
- Ampere (A): Defined by the elementary electric charge, representing the unit of electric current through the flow of a fixed number of elementary charges per second.
- Kelvin (K): Defined through the Boltzmann constant, representing thermodynamic temperature with a fundamental physical basis.
- Mole (mol): Defined by a fixed number of specified elementary entities (Avogadro constant), standardizing the unit for the amount of substance.
- Candela (cd): Defined by luminous intensity in a given direction for monochromatic radiation at a specified frequency and radiant intensity.
These definitions replace earlier editions and reflect the move towards physical constants-based SI units, enhancing measurement accuracy and reproducibility.
Applications
The standardized definitions in IEC 60050-112:2010/AMD2:2020 serve critical roles across electrotechnical and scientific disciplines:
- Precision measurement instruments benefit from consistent unit references, improving calibration and traceability.
- Electrical engineering leverages these definitions to maintain uniform standards in current, voltage, and resistance measurements.
- Thermodynamics and temperature control systems rely on the kelvin’s precise physical definition for accurate temperature regulation.
- Chemical analysis and materials science apply the mole unit for quantifying substance amounts in research and manufacturing.
- Lighting and photometry use the candela standard to quantify luminous intensity in LEDs, displays, and lighting fixtures.
- Educational and technical documentation utilize the precise terminology to ensure clear communication of measurement basis and unit usage.
Adherence to this amendment ensures compatibility and interoperability of devices, data, and specifications worldwide, fostering international trade and innovation in technology industries.
Related Standards
IEC 60050-112:2010/AMD2:2020 integrates directly with and complements:
- SI Brochure (9th Edition, 2019): The definitive guide on SI units by the International Bureau of Weights and Measures (BIPM), providing foundational definitions referenced in this amendment.
- IEC 60050 (International Electrotechnical Vocabulary): The broader vocabulary series that covers all electrotechnical terminology, establishing foundational terms and concepts across IEC standards.
- Other IEC standards on measurement and instrumentation: These use SI units defined here as the basis for performance criteria, test methods, and technical specifications.
- ISO/IEC Guide 99 (International Vocabulary of Metrology - VIM): Provides metrological terms aligned with SI definitions, complementing the terminology consistency at the international level.
Conclusion
IEC 60050-112:2010/AMD2:2020 is essential for professionals requiring authoritative definitions of quantities and units in electrotechnics and related fields. Its alignment with the latest SI definitions ensures accuracy, reliability, and global consistency, supporting technological development, measurement precision, and international standardization efforts.
Keywords: IEC 60050-112, International Electrotechnical Vocabulary, SI units, second, metre, kilogram, ampere, kelvin, mole, candela, electrotechnical standard, measurement units, SI base units, IEC amendment, international standards, physical constants.
Open preview (PDF)Amendment 2 - International Electrotechnical Vocabulary (IEV) - Part 112: Quantities and units
