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Old 23rd March 2014, 07:49 PM   #21
popilin is offline popilin  Argentina
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Quote:
Originally Posted by esltransformer View Post
Small correction, I am not a professional. I do this for a hobby and i have just a normal job at daylight
You can do it for hobby, but your transformers are realy professional.
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Old 23rd March 2014, 07:53 PM   #22
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I measured the impedance of some chokes i made in the past.
The influence of winding technique on the windingcapacity is clear.

btw i forget how much insulation i used for the "layers". I think it was 0,3mm.
The core i used was 0,05mm double c-core.

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Quote:
Originally Posted by popilin View Post
Tip#3 Interlayer insulation

Modern magnet wire has a breakdown voltage of more than 4 KV, so no need a great insulator, unless you make a very high voltage transformer.
However there are two more reasons for use insulation between layers

1- Decrease mechanical stress between layers

2- Decrease interlayer capacitance

One or two layers of 0.05mm polyester would be enough.

Last edited by esltransformer; 23rd March 2014 at 07:56 PM.
 
Old 23rd March 2014, 08:19 PM   #23
popilin is offline popilin  Argentina
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Quote:
Originally Posted by esltransformer View Post
I measured the impedance of some chokes i made in the past.
The influence of winding technique on the windingcapacity is clear.

btw i forget how much insulation i used for the "layers". I think it was 0,3mm.
The core i used was 0,05mm double c-core.
Sure, in an OPT you have many primaries in series, so winding capacitance will lower, but in an inductor there is no way, but vertical sectioning and/or increasing insulator.

Forget special winding techniques, they are beyond my winding lathe...
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Old 23rd March 2014, 08:23 PM   #24
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I like to use it in my transformers

Quote:
Originally Posted by popilin View Post
Sure, in an OPT you have many primaries in series, so winding capacitance will lower, but in an inductor there is no way, but vertical sectioning and/or increasing insulator.

Forget special winding techniques, they are beyond my winding lathe...
 
Old 23rd March 2014, 08:45 PM   #25
popilin is offline popilin  Argentina
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Quote:
Originally Posted by esltransformer View Post
I like to use it in my transformers
I also use vertical sectioning, but perfect layer technique?
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Old 23rd March 2014, 09:03 PM   #26
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Perfect not exists.

The reason that i posted some measurements of my own transformer in another thread (unfortunately destroyed by some other forum member) was that that is the only thing what is really important (ok, some people believe in listening only but that is far more tricky).

So the technical results are important. People can ask questions about design parameters, not if the wire is red or blue ....



Quote:
Originally Posted by popilin View Post
I also use vertical sectioning, but perfect layer technique?
 
Old 23rd March 2014, 09:15 PM   #27
popilin is offline popilin  Argentina
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Quote:
Originally Posted by esltransformer View Post
Perfect not exists.

The reason that i posted some measurements of my own transformer in another thread (unfortunately destroyed by some other forum member) was that that is the only thing what is really important (ok, some people believe in listening only but that is far more tricky).

So the technical results are important. People can ask questions about design parameters, not if the wire is red or blue ....
No, I mean perfect layer technique IIRC to minimize capacitance between turns in the winding, is a complete nightmare to do.

Edit: Be free to post what you want about your transformers, is always interesting and a source of inspiration.
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Last edited by popilin; 23rd March 2014 at 09:19 PM.
 
Old 23rd March 2014, 09:21 PM   #28
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Quote:
Originally Posted by popilin View Post
No, I mean perfect layer technique IIRC to minimize capacitance between turns in the winding, is a complete nightmare to do.

Edit: Be free to post what you want about your transformers, is always interesting and a source of inspiration.
Ahh, yes i agree.

btw if you have some measurements of your transformer you can make "plot" in a speadsheat as Excel.

btw2 i have some old test equipment what i can sell for : "as is" for free to you. Only shipment you have to pay.
I have to see what i have in my basement.....

Last edited by esltransformer; 23rd March 2014 at 09:31 PM.
 
Old 23rd March 2014, 09:32 PM   #29
popilin is offline popilin  Argentina
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Tip#4 Interwinding insulation

We must be very cautious here, because voltages involved can be very high, mostly in OPT when secondaries are grounded.

The best of the best insulator is NOMEX, you can kill three birds with one stone

1- Insulation, about 27 KV/mm for 0.08mm NOMEX 410

2- Low dielectric constant, about 1.6 for 0.08mm NOMEX 410

3- Heat resistant

Five to seven layers of 0.08mm would be enough for most cases.
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Old 23rd March 2014, 09:38 PM   #30
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Damn, i love Nomex but it is very expensive.



Quote:
Originally Posted by popilin View Post
Tip#4 Interwinding insulation

We must be very cautious here, because voltages involved can be very high, mostly in OPT when secondaries are grounded.

The best of the best insulator is NOMEX, you can kill three birds with one stone

1- Insulation, about 27 KV/mm for 0.08mm NOMEX 410

2- Low dielectric constant, about 1.6 for 0.08mm NOMEX 410

3- Heat resistant

Five to seven layers of 0.08mm would be enough for most cases.
 

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