Guys I want to ask a question about windings! So I know about the basic formula of the transformers it is:
N1/N2=U1/U2! So we know about the voltages of the primary and secondary windings e.g. 12volt primary and 220v secondary winding! But what about the windings? I seen a formulas like:
VA=Urms*Irms
RMS=Up/√2,
And some formulas that I don't understand a bit! But what is the relationship between this formulas and windings? I found a link for that but I didn't understood clearly what all that means!

https://www.google.com/translate?u=http://www.construyasuvideorockola.com/transformador.php&langpair=es|en&en=es&en=UTF8

 

There is no real definitive works on transformer design,, but basically the core size dictates the (K)va and the wire gauge sized to suit the applicable winding current.
For E I style, 3-4 turns/volt is common, for Toroidal, around 1.5 to 2 turns/volt.
Max.

P.S. Strange, this popped up in my 'New Posts'??

 

Here's a schematic of a transformer I pulled out of an old stereo.

Between terminals A & C is 65 VAC. Between E & G is 24.2 VAC. Between I & J is 5.1 VAC. On the other side is the 120 VAC input. SOME transformers have a center tapped primary designed to be connected either to 110 VAC or 220 VAC. Why? Because one transformer can be used in either situation where an end user may live in an area where the home electrical voltage is 220 VAC where in other areas it's 110 VAC.

As you can see from this diagram, there are many possibilities and reasons why a transformer may have only three legs, four legs, five legs or many legs. Also notice that the voltage between A & C has nothing to do with any of the other voltages. Such an arrangement of pin-out's can give an engineer a multitude of voltages to work with within a circuit, such as a stereo system.

 

What will you power with that crude and weak inverter circuit? Its output is a squarewave that is completely different to the sinewave produced by normal electricity. The output power from that inverter is only about 60W. It has no voltage regulation so its voltage will be too high when the 12V battery is charged then the voltage produced by the inverter drops when loaded and as the battery voltage runs down.
The 2N2222 transistors will fail soon because they have emitter-base avalanche breakdown in that very simple circuit.

 

How the transformer can convert something to DC? It only export AC!! One winding center taped, low DC.... I'm confused so much that I cannot recognize anything!! I thought that a transformer have 2 pins primary coil and 2 pins for secondary coil! From when the transformer have 2 or 4 or 5 or 6 or.......... Unlimited pins! I cannot understand this transformers! Can you explain better if you can, about this transformer? Thanks!!

A transformer does not convert power to DC! How is it that one represented as an engineer does not know that?? In fact, how is it that one represented as an engineer does not recognize a freehand symbol of a transformer?? Transformers can have many windings, and many of them do not have pins.
So I have a suggestion, which is to borrow a book on basic electricity, read it, and understand it. Then you will be able to ask questions that we can answer.

 

Awe geez! NECRO POST ALERT!

 

Awe geez! NECRO POST ALERT!

When I answered in post #22 it had popped up in my new posts and there wasn't the usual Legacy alert.! ??
Max.

 

@MaxHeadRoom Yeah, I understand that. I saw your post script, though I only saw it after I realized it was an old post.

 

Awe geez! NECRO POST ALERT!

SAY WHAT????

 

SAY WHAT????

See dates of posts #21 #22

 

See dates of posts #21 #22

OK, so it is an old post. Usually there pops up a warning about a post being old. Perhaps we lost that when the site was upgraded.

 

Perhaps we lost that when the site was upgraded.

Well, there's one way to check that. Open an old post and try to reply. See what happens. In fact, hang on a sec or two and I'll let you know what I find.

 

OK, went to the very oldest thread possible. Got this warning:

Thread Status: Hello Tonyr1084, The last response in this thread was more than 365 days go.

It is very likely that it does not need any further discussion and thus bumping it serves no purpose. It may be more appropriate to create a new thread with your question, and provide a link to this thread. If you feel it is necessary to make a new reply, you can still do so though. Your post will be reviewed and possibly be deleted.

(underline and italicized mine) Looks like a thread must be older than 365 days to get a warning. THIS thread is just about 3 years old. There SHOULD have been a warning. But I have no explanation why Max didn't see one.

 

I wonder if someone posted to it and reactivated it - then realized their mistake and then deleted their post, leaving this zombie thread to march on in search of brains.

 

I wonder if someone posted to it and reactivated it - then realized their mistake and then deleted their post, leaving this zombie thread to march on in search of brains.

That is what I had suspected
Max.