IEC 62973-1:2018

Overview

IEC 62973-1:2018 is an international standard established by the International Electrotechnical Commission (IEC) that defines the general requirements for batteries used in auxiliary power supply systems on railway rolling stock. This standard applies to various rechargeable battery technologies utilized across a wide range of train types, such as light rail vehicles, trams, metros, commuter trains, regional and high-speed trains, and locomotives. The primary goal of IEC 62973-1:2018 is to standardize electrical interfaces for batteries with different nominal voltages, facilitating consistent battery capacity sizing and performance evaluation for auxiliary power applications in railway operations.

Key Topics

• Battery Voltage and Electrical Interfaces
  IEC 62973-1:2018 specifies electrical interfaces for nominal battery voltages including 24 V, 32 V, 36 V, 48 V, 64 V, 72 V, 87 V, 96 V, and 110 V. The standard outlines requirements related to electrical parameters that consider battery load profiles, operating voltage ranges, and charging and discharging characteristics.

• Battery System Components and Design
  The standard defines terms and provides schematics for key battery system components, such as cells, monobloc batteries, crates, trays, and battery boxes. Mechanical design guidelines cover interface mechanisms (fixed, roller, and slide types), real estate on the vehicle for battery installation, accessibility, and ventilation requirements to ensure system safety and reliability.

• Charging and Discharging Requirements
  IEC 62973-1:2018 discusses battery charging parameters, including characteristics that optimize battery life and performance. Discharging requirements are detailed to support auxiliary loads with specific load profiles during normal and emergency operations, with emphasis on charge retention and prevention of deep discharge.

• Safety, Maintenance, and Fire Protection
  The standard includes mandatory safety and protection measures to safeguard the battery system and personnel. Topics covered include temperature compensation during charging, measures against deep discharge, fire protection strategies, and guidelines for routine maintenance.

• Testing and Verification
  Rigorous testing protocols such as type tests, dielectric tests, electrical characteristic tests, and load profile verification are specified. Tests ensure compliance with the standard, proper battery sizing, and operational reliability under shock and vibration conditions typical in railway environments.

Applications

IEC 62973-1:2018 applies to rolling stock auxiliary power supply batteries, critical for supporting electrical systems that cannot rely solely on the main traction power. Typical applications include:

• Emergency and backup power for onboard control, communication, and safety systems
• Auxiliary functions such as lighting, HVAC (heating, ventilation, and air conditioning), door operations, and onboard electronics
• Power resilience during main power interruptions or transitions through non-powered track sections (rail gaps)
• Maintenance and operational support for various train types including high-speed trains, commuter trains, trams, metros, and freight locomotives

Implementing the standard enables railway manufacturers, operators, and maintenance providers to ensure compatibility, safety, and performance consistency for battery systems regardless of battery technology or vehicle application.

Related Standards

• IEC 62973-2 and Beyond
  Subsequent parts of IEC 62973 focus on specific battery technologies and application-specific requirements, complementing the general framework provided in Part 1. These parts detail technology-specific parameters for lithium-ion, lead-acid, and other rechargeable battery chemistries used in rolling stock.

• Railway Electrical System Standards
  IEC 62973-1 aligns with other IEC and international railway standards governing electrical safety, power supply systems, and rolling stock design, ensuring holistic integration into the railway ecosystem.

• Battery Safety and Transport Regulations
  Standards governing battery transportation, storage, and safety (such as IEC 62133 and UN recommendations on the transport of dangerous goods) work alongside IEC 62973-1 to provide comprehensive battery management protocols.

Adoption of IEC 62973-1:2018 supports railway industry stakeholders in optimizing auxiliary battery systems through standardized design, testing, and operational guidelines. This standard promotes safer, more reliable, and interoperable battery solutions essential for modern railway rolling stock electrical systems.