IEC 60317-57:2010

Overview

IEC 60317-57:2010 (amended 2024) specifies requirements for polyamide‑imide enamelled round copper wire, class 220, used as winding wire in electrical equipment. The standard covers a sole coating based on polyamide‑imide resin (modifications allowed only if the resin’s chemical identity is retained) and defines thermal performance, mechanical and electrical tests, and acceptance criteria for this high‑temperature enamelled wire.

Key topics and technical requirements

• Thermal class: Class 220 - minimum temperature index 220 °C; minimum heat shock temperature 240 °C. The temperature index is not an operating temperature but an index related to long‑term thermal endurance.
• Conductor sizes / Grades: Grade 1 and Grade 2 cover nominal conductor diameters 0.071 mm to 1.600 mm (refer to IEC 60317‑0‑1 for nominal diameters).
• Coating chemistry: Sole coating based on polyamide‑imide resin; permitted resin modifications must retain the chemical identity.
• Mechanical and electrical tests: References and specific adaptations of general tests from IEC 60317‑0‑1 including:
  • Flexibility/adherence: Peel test with constant K = 75 mm.
  • Heat shock: Minimum 240 °C for the heat shock test.
  • Cut‑through: No failure within 2 minutes at 350 °C.
  • Breakdown voltage: Tested at an elevated temperature of 220 °C.
  • Resistance to abrasion: Detailed force requirements (Table 1) for nominal diameters from 0.250 mm to 1.600 mm; intermediate diameters take the next largest value.
• Tests marked inappropriate or without requirement: Resistance to refrigerants, solderability, heat bonding, dielectric dissipation factor and others are either marked “test inappropriate” or “test appropriate but no requirements specified” as noted in the document.
• Packaging: See Clause 30 and IEC 60317‑0‑1 for packaging requirements.

Applications and practical value

• Designed for high‑temperature windings in motors, generators, transformers, chokes, and other electromagnetic devices where thermal stability to Class 220 is required.
• Useful for manufacturers of enamelled winding wire, motor and transformer designers, electrical component suppliers, test laboratories, and procurement/specification engineers who need defined performance and test criteria for high‑temperature enamelled copper wire.
• Helps ensure material compatibility, predictable ageing/thermal behaviour and consistent manufacturing/acceptance testing.

Who should use this standard

• Winding wire manufacturers and formulators of polyamide‑imide enamels
• Motor, transformer and inductor designers and OEMs
• Test laboratories and conformity assessment bodies
• Procurement/specification teams requiring explicit thermal and mechanical criteria

Related standards

• IEC 60317‑0‑1 (General requirements for enamelled round copper wire) - this part must be read in conjunction with IEC 60317‑57.
• IEC 60317 series (other specific wire types)
• IEC 60851 (test methods for winding wires)
• IEC 60264 (packaging of winding wires)

Keywords: IEC 60317-57, polyamide-imide enamelled round copper wire, class 220, winding wire, temperature index 220, heat shock 240 °C, resistance to abrasion, breakdown voltage.