Making a 42mH coil

[convola]

• How can I make a 42mH coil with 35 x 0.05 litz wire

[Skippy]

Your starting point is working out the equivalent single solid core wire size. In this case, it is "Square-root of 35", multiplied by 0.05mm, = 0.296mm diameter.
Then you can use this value in the coil-calculator program ( on this Forum ) to work out number of turns, etc.

However, Litz wire is normally 'served' ( meaning 'cotton-covered' ), which increases the spacing between every wire, lowering the inductance value. The Litz wire itself also has integral space between the 35 wires, which can also lower inductance. So you will need to wind slightly more turns on your coil, maybe 5% or 10% more, to obtain the desired inductance.

[convola]

Your starting point is working out the equivalent single solid core wire size. In this case, it is "Square-root of 35", multiplied by 0.05mm, = 0.296mm diameter.
Then you can use this value in the coil-calculator program ( on this Forum ) to work out number of turns, etc.

However, Litz wire is normally 'served' ( meaning 'cotton-covered' ), which increases the spacing between every wire, lowering the inductance value. The Litz wire itself also has integral space between the 35 wires, which can also lower inductance. So you will need to wind slightly more turns on your coil, maybe 5% or 10% more, to obtain the desired inductance.

thanks for good explaination. I will try