***Update: The standard discussed in this post has been revised. The current edition, ANSI/NEMA MW 1000-2020: Magnet Wire, is available on the ANSI Webstore.
The new revision of ANSI/NEMA MW 1000-2016 – Magnet Wire has been released. This document, like its predecessors, is designed to present in concise and convenient form all existing NEMA standards for magnet wire, including those for round, rectangular, and square film-insulated and/or fibrous covered copper and aluminum magnet wire for use in electrical apparatus.
Furthermore, ANSI/NEMA MW 1000-2016 includes the definitions, type designations, dimensions, constructions, performance, and test methods for magnet wire generally used in the winding of coils for electrical apparatus. All of these considerations must be thoroughly comprehendible by manufacturers of magnet wire and products containing the material. Such products include transformers, speakers and headphones, motors, potentiometers, MRI machines, and any other systems that involve an electromagnet.
Due to the importance of magnet wire as a component of so many products, the ANSI/NEMA MW 1000 standard is updated annually, with the ANSI/NEMA MW 1000-2016 edition superseding the 2015 version. While this new revision doesn’t affect compliance with products manufactured during a time when a previous version of the standard was in effect, it is applicable for the fabrication of all current products containing magnet wire.
To simplify understanding of the many changes made to the lengthy standard document, an early section in ANSI/NEMA MW 1000-2016 identifies the updates made during the revision process, organizing them by the section of the document in which they are located. The following content was taken from this section of the standard.
Changes to the Introduction:
- Updated forward
- Updated “How to Use this Publication”
- Updated Tables of Contents
Changes to Part 1:
- 1.2.1 added for all normative references, with new references to ASTM B233, UL 746B and UL 1446
- 1.2.2 added for “other” non-normative references
- 1.4.1.2 revised to specify aluminum EC 1350 alloys
- 1.4.2 editorially reorganized for improved clarity
- 1.5.1.3 editorially modified for improved clarity
- 1.9.1 revised to expand and update the Part Numbering Identification (PIN) table
- Tables 13-19 replaced with former Tables E-4 and E-5; all subsequent tables renumbered
Changes to Part 2:
- MW 36-A revised to reference the Bend method for determining Dielectric Breakdown requirements for specified Heavy film-insulated wire sizes
- MW 36-C revised to clarify which Dielectric breakdown the requirements are determined according to the Bend method in 3.8.6
- MW 41-C and 44-C revised to clarify the methods used for determining compliance with Adherence and Flexibility requirements according to wire size
- MW 86-A, 86-C, 87-A and 87-C added as new specifications
Changes to Part 3:
- New Bend method added for determining compliance with Adherence and Flexibility requirements for large round glass fiber or polyester/glass fiber covered bare or film insulated wires
- Table 31 revised to indicate that elongation requirements for film-insulated round wire also apply to bare wire
- Tables 34 and 35 (formerly Tables 38 and 39) expanded to include sizes 14-37 AWG
Changes to Annex C:
- Revised to remain current with NEMA and IEC standards activities through 2015
Changes to Annex E:
- Revised to move Tables E-4 and E-5 to Part 1 as Tables 13 and 14
In addition to listing these changes, ANSI/NEMA MW 1000-2016 includes the exact page numbers where these changes can be located to assist further compliance.