IEC 60974-13:2021

Overview

IEC 60974-13:2021 - Arc welding equipment, Part 13: Welding current return clamp - specifies safety and performance requirements for welding current return clamps used in arc welding. It applies to clamps designed to make an electrical connection to the workpiece without tools and excludes clamps for underwater welding and plasma cutting. This second edition (2021) cancels and replaces the 2011 edition and contains technical revisions including updated test currents (corrected to 40 °C) and an updated reference to EN 50565-1:2014.

Key topics and technical requirements

• Scope and designation
  • Clamps are designated by the range of welding cable cross-sectional area they are intended to connect; test currents are defined per maximum cross-section (see Table 1).
  • The standard does not specify welding cables themselves.
• Environmental limits
  • Operation: −10 °C to +40 °C; storage/transport: −20 °C to +55 °C.
  • Relative humidity: up to 50% at 40 °C and up to 90% at 20 °C.
• Type tests and test sequence
  • Tests performed on new, fully assembled clamps at 10–40 °C include: visual inspection, temperature rise, retaining means, drop withstand, voltage drop, and final inspection.
• Electrical performance
  • Voltage drop test: measured arrangement with two clamps on a steel plate; voltage drop must not exceed 0.08 V per 100 A of test current.
  • Test currents in Table 1 cover a wide range of cable cross-sections (from small to very large cross-sections up to 240 mm²) with 60% and 100% duty-cycle values corrected for 40 °C.
• Thermal limits
  • Temperature rise limits: 40 K at the hottest spot normally gripped by the operator, 45 K at the cable connection (relative to ambient up to 40 °C).
• Mechanical and safety features
  • Requirements for retaining means, welding cable entry and connection, drop resistance, marking and instructions for safe use.

Applications and practical value

• Ensures safe, reliable electrical return connection between workpiece and welding power source in arc welding systems.
• Used by:
  • Manufacturers for design validation and type testing of return clamps.
  • Test laboratories and certification bodies for conformity assessment.
  • Procurement and safety engineers selecting clamps compatible with cable sizes and duty cycle demands.
  • OEMs integrating welding equipment (to ensure compatibility with welding power sources per IEC 60974-1).

Who should use this standard

• Welding equipment manufacturers, product designers, compliance officers, test labs, safety managers, and buyers specifying return clamps for industrial welding operations.

Related standards

• IEC 60974-1 (Welding power sources) - to be used in conjunction with this part.
• EN 50565-1:2014 - referenced for cable current capacity guidance.
• IEC 60050-151 - for relevant terms and definitions.

Keywords: IEC 60974-13, welding current return clamp, arc welding, voltage drop, temperature rise, test current, safety and performance requirements, IEC 60974-1, EN 50565-1.