Thermal Class
Insulation Type
NEMA Standard
IEC Standard
PDF DATA SHEET
105°C
MW15C/MW18C
NONE
155° C
MW79C
317-20
 
MW80C
317-21
 
180°C
MW82C
317-51
 
MW83C
NONE
 
MW30C
317-8
 
MW76C
NONE
 
MW77C
317-23
 
MW78C
NONE
 
NONE
317-37
 
200°C
MW44C/MW43C
NONE
 
MW45C/MW46C
NONE
 
MW74C
317-42
 
MW35C/MW36C
317-13/317-29
 
NONE
NONE
 
240°C
MW16C/MW20C
317-7/317-30
 

Insulations for Magnet Wire

 

 

Insulation Builds:

Insulation "build" refers to the thickness or the amount of insulation applied. The industry standard builds are as follows:
SINGLE
HEAVY (Sometimes called "double")
TRIPLE
QUAD OR QUADRUPLE

Note: SINGLE & HEAVY are the most common.

Guide to Insulation Callouts:

Thermal Class 105 C, NEMA MW 2-C,15-C Polyurethane (solderable @ 360 C, standard color is RED)
Formvar (Cryogenic use, oil filled transformers, superior abrasion resistance, non-solderable)
________________________________

Thermal Class 130 C / 155 C, NEMA MW 28-C, 80-C
Polyurethanes, Polyurethane-Nylons (Solderable, available in largest variety of colors)
________________________________

Thermal Class 180 C, NEMA MW 30-C, 77-C
Polyester-imide (non-solderable)
Solderable Polyester-imide
(solders @ 450C)

Note: Addition of Nylon overcoat to above qualifies to NEMA MW 76-C, 78-C
_________________________________

Thermal Class 200 C
Polyester Amide-Imide, NEMA MW 35-C
*Teflon (tm) film, No NEMA spec
_________________________________

Thermal Class 240 C, NEMA MW 16-C
Polyimide film
Other common names:
*ML (tm)
*Kapton (tm) Film

*Teflon, Pyre ML, and Kapton are all registered trademarks of DUPONT CORP.
_________________________________

Bondable Magnet Wire:

Bondable magnet wire is the combination of conventional film insulated magnet wire with the addition of a thermoplastic adhesive coating.

The main advantage in manufacturing is the ability to construct free-standing coils (coils without bobbins). The adhesive coatings are designed to be activated by heat (such as when baking in an oven) or solvents. Sometimes a combination of heat & solvent works best depending upon the specific application.

Bond Coatings

Polyvinyl Butyral 105 C
Heat Activation: 120 - 140 C
Solvent: Alcohol (Isopropyl)

Epoxy 130 C
Heat Activation: 130 - 150 C
Solvent: Acetone or Methyl Ethyl Keytone (MEK)

Polyester 130 C
Heat Activation: 130 - 150 C
Solvent: Methyl Ethyl Keytone (MEK)

Modified Polyester 155 C
Heat Activation: 220 - 260 C
Solvent: None

 

Technical Information (pdf files):