IEC TS 63346-1-1:2024

Overview

IEC TS 63346-1-1:2024 is a technical specification published by the International Electrotechnical Commission (IEC), providing standardized terminology for low-voltage auxiliary power systems (APS) used in power stations, substations, converter substations, and allied telecommunications equipment. This document defines terms critical for understanding, designing, installing, operating, and maintaining APS components and systems, ensuring a clear and consistent language is adopted across the electrical power industry.

This specification excludes terminology related to low-voltage auxiliary power systems in nuclear power stations and railway substations.

Key Topics

Terminology for Auxiliary Power Systems (APS)

• Auxiliary Power System (APS): A system that supplies electric power to low-voltage equipment in power stations and substations, ensuring normal and emergency power for auxiliary devices.
• Overcurrent Protective Device: Device designed to interrupt electric circuits when current exceeds preset levels.
• Primary and Secondary Cells: Definitions distinguishing between non-rechargeable (primary) and rechargeable (secondary) battery cells.
• Contingency Event: Failures or removals of critical elements that impact supply continuity.

APS Design Terminology

• Power Centre-Motor Control Centre (PC-MCC): Configuration of the APS combining power distribution and motor control.
• Redundancy Configuration: Intentional duplication of critical components or functions to enhance system reliability.
• Essential and Non-Essential Loads: Classification of auxiliary loads by their criticality, with essential loads requiring permanent or intermittent power.
• System Architectures: Definitions of radial systems (one-level, two-level) and ring systems describing power feed arrangements.
• Supply Types: Lead (normal), second (standby), emergency, and external supply definitions for power sourcing.
• Load Factors: Demand factor, maximum demand, and standby duration are defined to clarify load sizing and battery capacity requirements.

APS Equipment Terminology

• Battery Charger: Device converting AC to DC for battery charging and powering DC loads.
• Uninterruptible Power System (UPS): System combining converters, switches, and energy storage for continuous power supply during outages.
• Distribution Board and Change-over Board: Assemblies containing switchgear and controls for supplying loads and switching between power sources.
• Auxiliary Transformer: Transformer supplying auxiliary loads within stations or substations.
• Insulation Monitoring and Earth Detection: Devices monitoring insulation resistance and detecting earth faults on unearthed DC APS.

Operation and Maintenance Terms

• Equalization Charge: Extended battery charging to balance the state of charge across all cells.
• Boost Charge: Accelerated charging at higher-than-normal rates (information truncated in the source).

Applications

IEC TS 63346-1-1:2024 is essential for:

• Power Station and Substation Engineers: To uniformly understand and apply APS terminology, aiding design, installation, commissioning, and maintenance.
• Electrical System Designers: For ensuring reliability and clarity in specifying APS configurations and components.
• Standards Developers: To harmonize terms across IEC standards and related international normative references.
• Maintenance Personnel: Enabling proper identification of equipment and operational terms to sustain system health.
• Manufacturers and Suppliers: To align product definitions and documentation with international terminology standards.
• Telecommunications Infrastructure: Supporting power systems in communication sites related to power networks.

By providing unambiguous definitions, IEC TS 63346-1-1 helps prevent misinterpretations, reduces inconsistencies in documentation, and facilitates international collaboration.

Related Standards

Key related standards and references include:

• IEC 60050 Series: The International Electrotechnical Vocabulary (IEV), with extensive terminology on electrical and electronic domains.
• IEC 62040-1: Standards on uninterruptible power systems (UPS).
• IEC 61225: Battery charger standards.
• National and regional codes: Harmonization with national IEC member committee publications and regulations.
• Electropedia and ISO Online Browsing Platform: Online resources for terminology verification and browsing.

These related standards provide the broader framework within which IEC TS 63346-1-1 terminology fits, covering batteries, protective devices, UPS systems, power system architectures, and more.

Keywords: IEC TS 63346-1-1, low-voltage auxiliary power systems, APS terminology, power stations, substations, electrical standards, auxiliary equipment, power system design, IEC standards, uninterruptible power system, battery charger, power distribution, system redundancy, electrical power engineering.