What is magnet wire?

Magnet wire is an insulated copper or aluminum conductor used to wind motors, transformers, generators and any other electrical device where electrical energy is converted to mechanical energy.

The insulation will be either a film of varnish (enamel) or a covering of some type; such as polyester glass, mica or polyimide tape. The insulation provides electrical or mechanical properties to the wire.


What is winding wire?

Winding wire is another name for magnet wire. Winding wire is commonly used in Europe and Asia whereas magnet wire is used more frequently in North America.


What is insulation build?

Insulation build is the amount of enamel or covering added to the circumference of the wire. There are four different insulation builds for enamel: single, heavy, triple, and quad. There are many build variations available on other product lines.


Why are there different builds?

Insulation build is directly correlated to the desired dielectric strength or the degree of mechanical protection needed.


What does AWG stand for?

AWG stands for American Wire Gauge and identifies the diameter of a round wire.


Are there AWG sizes for rectangular wire?

No. AWG refers only to round and square wire.


What does NEMA stand for?

NEMA stands for National Electrical Manufacturers Association. NEMA is the trade association of choice for the electrical manufacturing industry. The NEMA 1000 standard defines the product criteria for the magnet wire industry.


What does ASTM stand for?

ASTM stands for American Society for Testing and Materials. ASTM International is one of the largest voluntary standards organizations in the world providing technical standards for materials, products, systems and services.


What does IEEE stand for?

IEEE stands for Institute of Electrical and Electronic Engineers. It is an organization providing technical and professional information for the electrical, electronic and aerospace industries.


What does UL stand for?

Underwriters Laboratory. It is an independent product safety certification organization.


What does Class 200 mean?

Class 200 is the IEEE designation for a wire that will perform at a “Continuous Operating Temperature” of 200 degrees Celsius for 20,000 hours. Craig Wire’s CW 200 is an example of a Class 200 wire.


What does Class H mean?

This is the letter designation for Class 180.


What is Class 155 and Class F?

These are the designations for a magnet wire that will perform at a “Continuous Operating Temperature” of 155 degrees Celsius for 20,000 hours. Examples of a Class 155 product are CW Mica and CW DPG.


Can I buy a Class 240 wire from CWP?

Yes. Craig Wire’s CW 240 TP is a Class 240 wire that is wrapped with a polyimide tape.


Why would one use rectangular wire instead of round wire?

Rectangular wire allows the engineer to design a motor with more copper in the unit. Round wire has more voids between the wires in the windings.


Does magnet wire have a shelf life?

There is no shelf life for magnet wire, except for mica covered magnet wire.


Does magnet wire require special storage conditions?

No it does not. However reels of rectangular and square wire should not be stored on its side.


How many 24″ reels are on a pallet?

Standard pallets of 24″ x 6″ reels will have 2, 4, or 8 reels.

Standard pallets of 24″ x 12″ reels will have 2 or 4 reels. 


How much does a 24″ reel of rectangular wire weigh?

The average weight on a 24″ x 6″ reel is 250 pounds. The maximum weight on a reel is 350 pounds.

The average weight on a 24″ x 12″ reel is 500 pounds. The maximum weight on a reel is 650 pounds. 


If I can buy 80 pounds of round wire on a reel and also in a pail why would I choose one over the other?

Reels are better to use in a high speed winding application. Pails in a high speed winding application have a tendency to tangle. Pails are better to use in a repair shop where high speed winding is not an issue. Also the pail has practical uses for the shop after the wire is used up.


What is a “whisker disc”?

A “whisker disc” is a disc with plastic filaments (whiskers) that is placed over the flange of a reel to add tension during the de-reeling of the wire to control de-reeling.


Can rectangular wire be purchased in a pail?


Any Questions?

Trina Perkins and Wendy Rampy are here to help.

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