NEMA MW 1000-2023 PDF

Full title and description

ANSI/NEMA MW 1000-2023 — Magnet Wire. Consolidated NEMA product standard containing general requirements, type specifications and test methods for round, rectangular and square film‑insulated and/or fibrous‑covered copper and aluminum magnet (winding) wire used in electrical apparatus.

Abstract

MW 1000-2023 defines material, dimensional, constructional and performance requirements for magnet wire and specifies required test methods. The document is arranged in three parts: Part 1 — general requirements (definitions, ordering information, dimensions and thermal classes); Part 2 — individual product specifications for specific insulation/conductor constructions; and Part 3 — test methods and tables of acceptance/test values. Annexes provide cross‑references to IEC/ASTM methods, packaging and handling guidance, refrigerant compatibility information and industry recommended practices.

General information

• Status: Superseded / redesignated — originally published as ANSI/NEMA MW 1000-2023; re-designated and maintained as NEMA MW 01000-2025 (equivalent content, redesignation effective in 2025).
• Publication date: July 11, 2023 (ANSI/NEMA MW 1000-2023).
• Publisher: National Electrical Manufacturers Association (NEMA); American National Standard (ANSI) approved.
• ICS / categories: 29.060 (Electrical wires and cables); 29.020 (Electrical engineering in general).
• Edition / version: ANSI/NEMA MW 1000-2023 (edition 2023) — content subsequently redesignated as NEMA MW 01000-2025.
• Number of pages: 301 pages (2023 edition, consolidated volume).

Scope

Applies to magnet (winding) wire constructions used for coils in electrical apparatus (motors, transformers, inductors, speakers, medical and industrial equipment, etc.). It sets out conductor materials (copper, aluminum), insulation/build options (film‑insulated, fibrous covered, rectangular and square profiles), dimensional limits, thermal class definitions and acceptance criteria. The 2023 edition clarifies that the standard itself does not establish quality assurance system procedures; QA programs and supplier quality systems are outside the scope unless specifically referenced by users.

Key topics and requirements

• Definitions, notation and ordering information for magnet wire products (Part 1).
• Dimensional tables (AWG and metric equivalents) and minimum insulation increases for round and non‑round profiles.
• Detailed Part 2 product specifications by MW number (insulation type, build, thermal class and intended conductor material).
• Part 3 test methods: dielectric breakdown, continuity, bond strength, solubility/scrape resistance, thermal endurance, deflection/springback, pulse endurance and others.
• Refrigerant extraction and dielectric breakdown after refrigerant conditioning (updated in 2023 to address R‑22 phase‑out, replacement refrigerants and refrigerant oil compatibility considerations).
• Acceptance/test value tables for each property and construction; shot‑electrode methodology for large/rectangular wire breakdown testing.
• Annexes providing cross‑references to IEC/ASTM test methods, packaging/reel dimensions, recommended winding tensions and special test procedures (e.g., zero‑defect fully insulated wire).
• Designation of certain legacy specifications as obsolete and updates to polyester‑based film insulation nomenclature.

Typical use and users

Primary users are magnet wire manufacturers, motor/transformer/inductor designers and manufacturers, procurement/specification engineers, test laboratories and quality engineers. The standard is used to specify product requirements in purchase orders, to develop and qualify wire constructions, and to define acceptance testing for incoming materials and finished windings.

Related standards

IEC 60851 series (winding wires — test methods and specifications), applicable ASTM test methods referenced in MW 1000 annexes, and NEMA companion publications such as NEMA MW 750, MW 765, MW 780, MW 785 and MW 820. The 2023 volume also cross‑references IEC specifications where equivalent tests exist.

Keywords

magnet wire, winding wire, enameled wire, film‑insulated, fibrous‑covered, AWG, dielectric breakdown, refrigerant extraction, thermal class, NEMA, ANSI, test methods, motor wire, transformer wire.

FAQ

Q: What is this standard?

A: ANSI/NEMA MW 1000-2023 is the consolidated NEMA product standard for magnet (winding) wire that establishes definitions, dimensional requirements, product specifications and test methods for copper and aluminum magnet wire constructions.

Q: What does it cover?

A: It covers general requirements (Part 1), individual product specifications for specific insulation/conductor constructions (Part 2), and the associated test methods and acceptance values (Part 3). It also includes annexes with cross‑references to IEC/ASTM methods, packaging guidance, refrigerant compatibility information and recommended industry practices.

Q: Who typically uses it?

A: Wire manufacturers, motor/transformer/inductor designers and manufacturers, procurement and specification engineers, independent test laboratories, and quality/inspection personnel use the standard to specify, qualify and test magnet wire.

Q: Is it current or superseded?

A: The edition was published July 11, 2023 as ANSI/NEMA MW 1000-2023. In 2025 NEMA re‑designated the document series (NEMA MW 01000-2025) and continues maintenance under that designation; the 2023 text is treated as the prior edition and the 2025 redesignation is the current maintained document. (Redesignation and related maintenance actions became effective in 2025.)

Q: Is it part of a series?

A: Yes — MW 1000 is a consolidated NEMA magnet wire volume containing many MW‑xx product specifications; it is supported by several companion NEMA documents (MW 750, MW 765, MW 780, MW 785, MW 820, etc.) and cross‑references IEC and ASTM test methods.

Q: What are the key keywords?

A: Magnet wire, winding wire, enameled wire, film‑insulated, fibrous covered, dielectric breakdown, refrigerant extraction, thermal class, NEMA, ANSI, test methods.