I don't think the site from edcorusa is very reliable but as i say before the difference with for a µrel=480 is not that big.
Here is a site i use: http://www.nssmc.com/product/catalog_download/pdf/D004je.pdf
M6=35z155 (the data is for un-cut cores so EI will be less good)
I use 23zh85 and 30zh105 (i have also other materials)
Here is a site i use: http://www.nssmc.com/product/catalog_download/pdf/D004je.pdf
M6=35z155 (the data is for un-cut cores so EI will be less good)
I use 23zh85 and 30zh105 (i have also other materials)
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I was having a look in the site where i bought the EI cores i have, and they say that they have high quality EI cores, UI cores, and 3UI cores...does someone know what are UI and 3UI cores ?
Thanks
Thanks
For UI you need two bobbins and 3UI is for three phase (power)transformers.
UI is very useable for PP transformers
btw for really high quality c-cores, series sm; se; sg; su or s3u, are much better
See also:
http://www.waasner.de/produkte/transformatorenbauteile/transformatorenbauteile/
UI is very useable for PP transformers
btw for really high quality c-cores, series sm; se; sg; su or s3u, are much better
See also:
http://www.waasner.de/produkte/transformatorenbauteile/transformatorenbauteile/
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That "horizontal partitioning" is called "Vertical Sectioning" because original winding is divided into vertical sections, is just semantic anyway. 😉
Nothing to thank, we are here to help each other. 🙂
If you have any doubt, please ask me, if I know the answer no problem, if I don't, I will sign to you an "explainenture" remember that I think slowly. 😀
Magnetic materials has a magnetic permeability µ, that is in the manufacturer datasheet, if you add an air gap that magnetic permeability is strongly decreases to the µeff value, I bet that, as is common today, you use mks units, the worst of the worst for electromagnetism, introducing µ, µo, ε, εo, with its own units, this is a madness to confuse people. 😉
Fortunately Edcor guys use cgs units, =Gauss, [µ]=dimensionless. 🙂
Dumb people like me, we love cgs units, because all is easier. 😀
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Tip#6 How to evaluate distributed capacitance
Suppose a winding like fig.2, we have N primary layers, at point Mp1
Ce = (2.5/N)² C1
At point Mp2
Ce = (3.5/N)² C2
At point Mp3
Ce = (8.5/N)² C3
At point Mp4
Ce = (9.5/N)² C4
Where Ci is each interwinding capacitance between P ans S, so total distributed capacitace
Cd = (2.5/N)² C1 + (3.5/N)² C2 + (8.5/N)² C3 + (9.5/N)² C4 +...
If C is the average interwinding capacitance, then
Cd ≈ C [(2.5/N)² + (3.5/N)² + (8.5/N)² + (9.5/N)² +...]
Suppose a winding like fig.2, we have N primary layers, at point Mp1
Ce = (2.5/N)² C1
At point Mp2
Ce = (3.5/N)² C2
At point Mp3
Ce = (8.5/N)² C3
At point Mp4
Ce = (9.5/N)² C4
Where Ci is each interwinding capacitance between P ans S, so total distributed capacitace
Cd = (2.5/N)² C1 + (3.5/N)² C2 + (8.5/N)² C3 + (9.5/N)² C4 +...
If C is the average interwinding capacitance, then
Cd ≈ C [(2.5/N)² + (3.5/N)² + (8.5/N)² + (9.5/N)² +...]
Tip#7 Where to connect +B
Distributed capacitance is increased from +B (0 VAC) to anode of the valve, U VAC, so the best place to connect +B is on the outer side of the whole winding, far from core, because each interwinding capacitance is increased from inside to outside.
Distributed capacitance is increased from +B (0 VAC) to anode of the valve, U VAC, so the best place to connect +B is on the outer side of the whole winding, far from core, because each interwinding capacitance is increased from inside to outside.
Popilin,
I went back and using the formuale you posted calculated teh values for the transformer I wound.
Usingenglish units formuale I never could resolve teh winding count.
Using the formulae you posed I came out within 5%!
TKS
Steven
I went back and using the formuale you posted calculated teh values for the transformer I wound.
Usingenglish units formuale I never could resolve teh winding count.
Using the formulae you posed I came out within 5%!
TKS
Steven
Hi Steven
Glad to know that equations works so well for you, indeed, I suffered the same in early days, that's the reason I derived it.
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Before this thread I believe Juan was a bit crazy. 😡
Now, I'm sure Juan is too much crazy.:-D
But still is my friend.
Now, I'm sure Juan is too much crazy.:-D
But still is my friend.
Tip#8 Vertical Sectioning
Let's consider now a normal winding as in fig.3a, suppose that interwinding capacitance is C and interlayer capacitance is 3C, total distributed capacitance is
Cd ≈ C [(2.5/12)² + (3.5/12)² + (8.5/12)² + (9.5/12)²] ≈ 1.26 C
Total winding capacitance is
(Cw)⁻¹ ≈ (3C)⁻¹ {2 {(4/3x3) [1-(1/3)]}⁻¹+ {(4/3x6) [1-(1/6)]}⁻¹}
Then
Cw ≈ 0.25 C
Then total shunt capacitance
Cs = Cd + Cw ≈ 1.51 C
Let's consider now a split winding as in fig.3a, all areas are halved, so
Cd ≈ (C/2) [(5.5/24)² + (6.5/24)² + (17.5/24)² + (18.5/24)²] ≈ 0.63 C
Total winding capacitance is
(Cw)⁻¹ ≈ (3C/2)⁻¹ 4 {(4/3x6) [1-(1/6)]}⁻¹
Then
Cw ≈ 0.07 C
Then total shunt capacitance
Cs = Cd + Cw ≈ 0.7 C
It works!!! 😎
Let's consider now a normal winding as in fig.3a, suppose that interwinding capacitance is C and interlayer capacitance is 3C, total distributed capacitance is
Cd ≈ C [(2.5/12)² + (3.5/12)² + (8.5/12)² + (9.5/12)²] ≈ 1.26 C
Total winding capacitance is
(Cw)⁻¹ ≈ (3C)⁻¹ {2 {(4/3x3) [1-(1/3)]}⁻¹+ {(4/3x6) [1-(1/6)]}⁻¹}
Then
Cw ≈ 0.25 C
Then total shunt capacitance
Cs = Cd + Cw ≈ 1.51 C
Let's consider now a split winding as in fig.3a, all areas are halved, so
Cd ≈ (C/2) [(5.5/24)² + (6.5/24)² + (17.5/24)² + (18.5/24)²] ≈ 0.63 C
Total winding capacitance is
(Cw)⁻¹ ≈ (3C/2)⁻¹ 4 {(4/3x6) [1-(1/6)]}⁻¹
Then
Cw ≈ 0.07 C
Then total shunt capacitance
Cs = Cd + Cw ≈ 0.7 C
It works!!! 😎
You're right looking at shunt capacitance but this kind of sectionizing rises Leakage Inductance to the sky 🙁
Yves.
Yves.
Thanks! But I do not deserve.
That's why my wife calls me Calculín. 😀
Agree, but the trick is to lower shunt capacitance, nothing more, sometimes can be useful. 😉
I will make calculations for cross connected primaries, I bet leakage inductance will be not so high, but not today... 🙂
Maybe for a small SMPS transformer, but with many primary layers is a nightmare to implement, thanks, but no thanks. 😉
Z windings really help downloading capacitance. In a obscure project I'm working on, it helped me too much, as to reduce capacitance almost 3 times less.
Certainly, Popilin, can you explain where a "humble TV repairman" get those complex equations and demonstrations?.
Something doesn't close for me...
Certainly, Popilin, can you explain where a "humble TV repairman" get those complex equations and demonstrations?.
Something doesn't close for me...
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