About NEMA MW 1000
MW 1000 is approved as an American National Standard through the NEMA MW 1000 Consensus Body accredited by the American National Standards Institute (ANSI). The Consensus Body consists of magnet wire participants including wire manufacturers, end users, and other general interest stakeholders.
What is magnet wire?
Magnet wire (also known internationally as winding wire) is an insulated electrical conductor, usually copper or aluminum that when wound into a coil and energized, creates a useful electromagnetic field. Without magnet wire, electricity is essentially useless. Around 90% of all electrical energy requires modification using magnet wire to be of any use.
NEMA MW 1000 Highlights
The following is a summary of changes from MW 1000-2018 that appear in the 2020 edition or are under development for a future edition:
Part 1—General
Revisions to Table 3, Dimensions for Self-Bonding Wire to expand the wire size range to include 8-13.5 AWG, providing the magnet wire industry a set of standard dimensional film and bond coat increases encompassing the entire range of self-bonding wire sizes that industry currently manufactures
Revision of requirements in clause 1.4.1.3 to remove the physical properties requirements for aluminum conductors
Correction to clause 1.5.1.3, Application of Insulation, to indicate that insulation tape coverings, not fibrous coverings, shall be wrapped firmly, closely, evenly, and continuously around the wire
Part 2—Specifications
Revisions to specifications for polyvinyl acetal film insulated wire to harmonize the Heat Shock requirements for consistency
New specification for MW 16-A Polyimide (Thermal Class to be determined), with requirements to eventually be added for satellite applications
Revisions to MW 33-A and MW 33-C specifications for paper tape covered rectangular magnet wire to better align with their counterpart round wire specifications
Revisions to MW 102-A and MW 102-C to align their dielectric breakdown, springback and continuity requirements with the MW 35 series, which is the base specification for “Polyester (amide)(imide) Overcoated with Polyamideimide” constructions
New MW 88-C specification for polyvinyl acetal film insulated rectangular aluminum wire with self-bonding overcoat, with accompanying amendments to include minimum dimensional increases due to the bonding layer, and a lap shear bond strength test
New MW 103-C specification for Polyester Overcoated with Polyamideimide with Self-Bonding Overcoat
New MW 122-C specification for Polyamideimide with Self-Bonding Overcoat;
Part 3—Test Methods
Revision to the circumferential cut method for determining adherence and flexibility properties, to include photos of a typical fixture and specimen preparation
Appendices
Revisions to Appendix H for Fully Insulated Wire, to align with amendments to IEC 60851-5
Under Development:
Revisions to the refrigerant resistance test to replace the use of R-22 with the use of alternative refrigerants listed in Appendix F
How to Use MW 1000
In the Table of Contents, the Part 2 specifications are first listed in order according to MW specification number, then by Thermal Class for easy reference to a particular type of magnet wire.
To properly use MW 1000, first, review Part 1 for general information, then locate the specification in Part 2 for the particular type of insulation and conductor of interest. Part 2 is arranged in MW number order as shown beginning on page ii. The dimensions for each Part 2 MW type are provided in Part 1 beginning with Table 1. The specification in Part 2 will indicate the performance requirements to be met and references the test procedures and corresponding test values to be attained in Part 3.
Part 1 deals with general information common to all types of magnet wire found in Part 2, including reference documents, definitions, general material requirements, manufacturing information, test conditions and parameters, thermal class information and ordering information. Part 1 also includes dimensions in both AWG and equivalent metric sizes (in mm) for bare wire, minimum insulation increase, and overall dimensions for all MW specifications in Part 2.
Part 2 has all of the NEMA specifications for the particular types of magnet wire listed in the Table of Contents, identified and ordered by “MW” number. The MW number is followed by a “-C” or “-A” to identify the conductor type, copper or aluminum. These specifications provide all of the performance requirements for magnet wire for various types of coatings and/or coverings. Insofar as possible, the product specifications are complete on one sheet since they are arranged to include only one insulation or covering per sheet. The title identifies the product, for example, MW 15-C, Polyvinyl Acetal Round Copper Magnet Wire, while MW 15-A covers the aluminum version of the same generic product.
Part 3 contains the test procedures to be followed and the corresponding tables of specific test values to be attained in determining compliance with the requirements given in Part 2. The requirements are consolidated with the test procedures and testing parameters for a given property. The Table of Contents provides a useful index of the main test paragraphs, beginning on page viii.
Appendix A provides a cross-reference between MW 1000 test procedures and those published by the American Society for Testing and Materials (ASTM International) and the International Electrotechnical Commission (IEC).
Appendix B provides definitions, requirements, and recommended test procedures for reusable magnet wire packaging, standardized dimensions for spools and reels, and standard formatting for the labeling of magnet wire products.
Appendix C provides a cross-reference of MW specifications with those published by the IEC.
Appendix D provides the formulas used for determining dimensional requirements, minimum dielectric breakdown voltage, and cross-sectional areas and conductor resistance
Appendix E defines the dimensional criteria for ranges of sizes of rectangular bare, film insulated, and fibrous covered magnet wire. These tables provide the general rules and guidelines for various rectangular magnet wire products that are not standard as defined in Part 1. For convenience, cross-references to the corresponding tables in Part 1 are provided.
Appendix F provides important information on selected refrigerants that could be used as alternatives to monochlorodifluoromethane (refrigerant R-22), including chemical compositions, boiling points, critical pressures and critical temperatures.
Appendix G provides industry recommended winding tensions for de-reeling of magnet wire onto end user winding equipment.
Appendix H defines the requirements and test procedures for zero-defect fully insulated magnet wire (FIW).
Appendix I provides a recommended method for repeated scrape resistance, commonly specified by magnet wire end users.
The content is from the NEMA Standards page, you can visit https://www.nema.org/directory/products/mw-1000 for more NEMA Standards content