AWG wire used in the primary winding of RDR-321 17 W Dual Output Flyback Supply for LCD Monitor

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I am designing a flyback power supply that it is quite similar to the one developed in the document RDR-321.
The fact, is that I am using PIXIs for designing according to my specifications and I am taking RDR-321 as a start point.

However, I cannot understand well why the primary is not winded with AWG30 according to the PIXIs spreadsheet cell D93.
The primary winding is performed with AWG32 single wire, which in turns has less cir-mil than AWG30.
Is that correctly specified in the transformer construcion and diagram depicted in the document?

I would understand that a AWG32 bifilar wire would be used instead, but I do not know I am right, according to an18.pdf (transformer construction).

In other words, CMA = (N*CM) / IpRMS -----> CMA = (2*64) / 0.33A = 387,8 which is between the range of 200-500 CMA.

It would almost filled the section layer (0.93) if AWG32 bifilar were used, if I am right.

Another thing I would to ask for is that I cannnot reproduce exactly the spreadsheet of the RDR-321. The secondary windings specified in RDR-321 reported a failure in the PIXIs.
Could you please provide me that spreadsheet?
If not, I attach the one I have been working on and hope you can tell me what is wrong.

If I can solve these questions my new desing will be developed quickly.


LinkSwitch-HP_RDR_321_document.pixls49.5 KB

Is anyone there? Has anyone read my post?
I would appreciate a reply in order to clarify this.


Thanks for providing the spreadsheet of your design. Let me review this and try to understand the problem, then I'll get back to you as soon as I can.

Thank you very much.