IEC 60974-4:2025

Overview

IEC 60974-4:2025, published by the International Electrotechnical Commission (IEC), sets forth comprehensive test procedures for the periodic inspection and testing of arc welding equipment to ensure electrical safety. This fourth edition supersedes the 2016 version, incorporating significant technical revisions to address evolving safety and maintenance requirements. The standard specifically applies to power sources used in arc welding and allied processes, designed under IEC 60974-1 or IEC 60974-6, and also extends its testing framework to stand-alone ancillary welding equipment. Unique to this edition is the inclusion of requirements for battery-powered arc welding power sources, detailed in Annex D.

IEC 60974-4:2025 is vital for stakeholders responsible for routine inspection, maintenance, and repair testing of welding power sources, thereby safeguarding operational safety and compliance with international regulations. It excludes testing of new or engine-driven power sources, focusing instead on in-service equipment to sustain electrical safety standards.

Key Topics

• Scope and Applicability
  The standard targets periodic inspection and testing after repairs and during maintenance, focusing on ensuring electrical safety across various arc welding power sources, including battery-powered units.

• Test Procedures
  Detailed procedures include visual inspections, insulation resistance tests, continuity checks of protective circuits, touch current measurements, and no-load voltage determinations to identify potential electrical hazards.

• Safety Measures
  It emphasizes protection against electrical shock, requiring specific testing of welding circuits and ancillary equipment linked to the power source.

• Personnel and Equipment Qualifications
  IEC 60974-4 mandates qualified personnel to conduct tests using calibrated measuring instruments, aligning with IEC 61557 series for electrical safety measurements and referencing EN 50699 for measurement examples.

• Functional Testing
  Beyond safety checks, the standard outlines functional tests on supply-circuit switches, voltage-reducing devices, magnetic gas valves, and control lamps to confirm overall equipment reliability and operational integrity.

• Documentation and Reporting
  The standard requires comprehensive test reports post-inspection or repair, including labelling that reflects compliance status and test outcomes, ensuring traceability and accountability.

• Special Considerations for Battery-Powered Equipment
  Annex D provides additional testing guidelines tailored for battery-powered welding power sources, including charger testing and safety protocols unique to portable and rechargeable units.

Applications

IEC 60974-4:2025 is essential for industries and organizations utilizing arc welding equipment, focusing on:

• Manufacturers and Maintenance Services
  Ensuring their welding power sources and ancillary equipment undergo thorough periodic inspections and safety testing to comply with international safety standards.

• Industrial Safety Programs
  Integrating these test procedures into regular safety audits and preventive maintenance schedules to reduce equipment-related electrical hazards.

• Quality Assurance and Compliance
  Supporting certification bodies and compliance officers in verifying adherence to global electrical safety standards for welding equipment.

• Battery-Powered Welding Equipment Users
  Addressing the growing use of portable and battery-powered power sources in welding, the standard guides safe maintenance and inspection practices, enhancing operator safety and equipment longevity.

Related Standards

Key related IEC standards complementing IEC 60974-4:2025 include:

• IEC 60974-1:2021 – Arc welding equipment – Part 1: Welding power sources
  Defines the general requirements for welding power sources, forming the foundation for the inspection and testing procedures in Part 4.

• IEC 60974-6:2015 – Arc welding equipment – Part 6: Limited duty equipment
  Covers testing standards specific to limited-duty welding equipment, used in conjunction with Part 4 for ancillary devices.

• IEC 61557 Series – Electrical safety in low voltage distribution and industrial systems
  Provides guidelines on measuring instruments and methods for ensuring electrical safety, referenced extensively in IEC 60974-4.

• IEC 61140 – Protection against electric shock
  Outlines common aspects for installation and equipment safety, underpinning the protective measures mandated in the standard.

• EN 50699 – European Standard offering measurement examples adopted in this edition for enhanced testing accuracy.

Adherence to IEC 60974-4:2025 and its related standards promotes operational safety, compliance, and reliability in the management of arc welding equipment across global industrial sectors.