How to choose the right enameled wire?

Enameled wire is mainly used for winding coils, such as transformers, motors, and inductors. How to choose enameled wire can not only improve our work efficiency, but also save costs. Choosing the right enameled wire requires comprehensive consideration of application scenarios, electrical properties, mechanical properties, and environmental factors.

Considerations for Selecting enameled magnet wire

• 1. Determine the application scenario

When choosing enameled wire, we must first clarify the purpose of the enameled wire, for example:

◆ High-frequency equipment (such as high-frequency transformers, inductors): need to pay attention to the skin effect, and may require multiple strands of fine wire or special wire.

◆ High-power equipment (such as motors, power transformers): focus on current carrying capacity and temperature resistance.

◆ Micro equipment (such as headphone coils, sensors): require extremely fine wire diameters (such as 0.02mm~0.1mm).

◆ High-temperature environment (such as automotive motors, industrial equipment): choose high-temperature resistant insulating paint (such as polyimide).

• 2. Conductor material selection

◆ Enameled copper wire: high conductivity (low resistance), high cost, suitable for most scenarios.

◆ Enameled aluminum wire: light weight, low cost, but high resistance, requires thicker wire diameter compensation, suitable for weight-sensitive scenarios (such as drone motors).

◆ Coated wire: such as silver-plated copper wire can improve high-frequency performance, but the cost is higher.

• 3. Calculate wire diameter (key step)

The wire diameter selection must meet the current carrying capacity and space constraints. We can quickly match the current and wire diameter by looking up the table (such as IEC 60317 standard) according to the current carrying formula. If the winding window is limited, it is necessary to balance the current carrying capacity and the number of turns (for example, use a thinner wire diameter but increase the number of parallel strands). This determines whether to choose round wire or flat wire.

• 4. Insulating paint type and temperature resistance grade

• 5. Withstand voltage and insulation strength

◆ Insulating layer thickness: For high voltage applications (such as >1kV), thick paint film (such as Grade 2 or Grade 3) is required, and standard paint film (Grade 1) can be selected for conventional low voltage equipment.

◆ Test verification: Ensure insulation reliability through withstand voltage test (such as 1kV/mm for 1 minute).

• 6. Environmental adaptability

◆ Wet environment: choose moisture-proof paint (such as polyesterimide).

◆ Chemical corrosion: solvent-resistant paint (such as polyimide).

◆ Vibration environment: paint layer with high mechanical strength (such as polyamide-imide).

• 7. Certification and standards

◆ International standards: IEC 60317 (international), NEMA MW 1000 (USA), JIS C 3202 (Japan)

◆ Industry certification: UL certification (safety), RoHS (environmental protection), AEC-Q200 (automotive electronics).

• 8. Precautions when replacing or repairing

◆ Measuring old wires: Use a micrometer or laser diameter gauge to accurately measure the original wire diameter.

◆ Equivalent substitution: If the original wire diameter is not available, it can be compensated by connecting multiple strands of thin wire in parallel or adjusting the number of turns.

• 9. Cost optimization

◆ Aluminum instead of copper: Use aluminum wire to reduce costs in scenarios where resistance increase is allowed.

◆ Simplified paint layer: Low temperature resistance grade enameled wire can be selected in non-high temperature environments.

Original Source:Magnet Wires for Power Industry