Hi guys, On the link below there is a button labelled, "Click here for more information in PDF" The are two formulas #2 and #3 they are not legible in my PDF reader. Can anyone read it and post them for me. Also, from what I can see, example 1 uses formula #3 but I don't see that the numbers jive. What did I miss.
The information just isn't there reliably. But go to the orginal source, not this NE Wire rehash:
Page 37 has equation 2,
Formula 3 is just a fudge factor for the increase in electrical length of Litz wire
Rdc = (Rs*(1.02)^Nb * (1.03)^Nc)/Ns
They've used one more decimal point in the example than in the formula (wherever they got that from) and incorrectly tacked a zero onto the rounded result, but aside from those nit-picks the numbers do seem to jive.
Ick. It looks as if they didn't actually bother to embed the text of those formulae in the PDF. Instead, they took a (low-resolution) screen capture from a window, and pasted the capture into the document as a pixelized graphic.
Formula 2 appears to be
2 Resistance to Alternating Current ( N Di ) --------------------------------- = H + K ( ------ ) G Resistance to Direct Current ( Do ) and refers to Terman "Radio Engineers Handbook" pages 30-83.
G is the "eddy current basis factor",
4 G = ((Di * sqrt(F) / 10.44)) Formula 3 appears to be
Nb Nc Rs (1.02) (1.03) Rdc = ----------------------- Ns
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior