EP 12 - Comment fabriquer vos bobines

Introduction

This tutorial provides a comprehensive guide on how to create coils on toroids, including selecting the right toroid, calculating the coil specifications, winding the coil, and testing it with various meters. Whether you're a hobbyist or a professional, this process is crucial for building efficient inductors for your electronics projects.

Step 1: Choose the Toroid

• Identify the purpose of your coil to determine the specifications required.

Select the right toroid based on your project needs. Consider

• Material (e.g., ferrite or powdered iron)
• Size and shape
• Use a color code chart for toroids to assist with selection. View the color code chart here.

Step 2: Utilize Coil Calculation Software

• Download and install Coil64, a freeware tool for calculating coil parameters. Get Coil64 here.

Input necessary parameters such as

• Desired inductance
• Number of turns
• Core dimensions
• Analyze the output to determine required wire type and length for winding.

Step 3: Wind the Coil

• Prepare your workspace with the toroid and enameled copper wire.

Follow these winding steps

• Secure the toroid on a stable surface.
• Start winding the wire around the toroid, ensuring uniform spacing between turns.
• Count the turns carefully as they directly affect the inductance.
• Finish the winding by securing the ends of the wire.

Step 4: Test the Coil

• Gather testing equipment such as an LCR meter (e.g., DER - DE5000).

Connect the meter to the coil

• Use the correct leads for accurate measurement.
• Make sure to measure in a four-wire configuration to eliminate resistance effects.

Record the readings

• Inductance (L)
• Quality factor (Q)
• DC resistance (DCR)

Step 5: Perform Additional Measurements

• Use other meters like TC1 and LC200A for cross-verification of your coil measurements.
• Make sure to check DCR accurately in a four-wire setup to avoid errors.

Step 6: Calculate Quality Factor

• Understand the concept of Quality Factor (Q): It indicates the efficiency of your coil.
• Calculate Q using the formula:

  Q = (Inductive Reactance) / (DC Resistance)
  

• Use the measurements obtained from your testing equipment to perform this calculation.

Conclusion

In this guide, we covered the essential steps for fabricating your own coils on toroids, from selection to testing. By following these processes, you can create efficient inductors tailored for your electronic applications. For further exploration, consider purchasing materials from recommended suppliers and experimenting with different toroidal cores and wire types. Happy building!