It calculates the coils and construction parameters necessary
to realize an inductor with the needed inductance value.
It is adapt for closed coils in free air (without core) or with not magnetic (circular) core.
Dimensioning is done with successive approximations using Wheeler method until obtain valid results and inner acceptable tolerances.
Required inductance value
Diameter of the enamelled wire for coil:
Ø f (mm)
Inner diameter of the coil:
Ø i (mm)
Pack form ratio (L / H):
L / H
|Imposed inner diameter||Ø i||mm|
|External diameter||Ø e||mm|
|Total required coils||n.|
|Turns per layer||n.|
|Minimal length of the wire (closed coils)||m|
|Wire resistance (copper)||ohm|
|Wire weight (copper)||kg|
The support for the coil can be removed after the realization if during it, at the end of every layer, is spread a layer of glue or resin for winding.
Wire section used must be tailored for the current (1-3 A mm˛), to valuate it according to the power see page Dimensioning of cables for passive speakers. To exceed with the wire section is not an error.
To verify the inductance value realized see Resonant frequency of L-C circuit, with a capacitor (e.g. 1 µF) in parallel. Varying the input value of the inductance until obtain the same resonant frequency measured using a signal generator and the oscilloscope.