jcatiwalaan,
if you are lucky,sir tony must be in pasig
otherwise he is in russia
or,,,,,,
you can follow his leads
do you have any rewinding experience before?
for a core 2in. center leg stacked to about 5.75inches you will need,
primary, 148 turns #13AWG copper wire,
secondary, 4coils quafillar wound 25turns #12AWG copper
note that i use american standard gauge, i know that in India, the British system is used, so make adjustment to suit your local conditions...
i based my computations on the assumption that you will be using the cheaper non grain oriented steel......
if you are lucky,sir tony must be in pasig
otherwise he is in russia
or,,,,,,
you can follow his leads
do you have any rewinding experience before?
for a core 2in. center leg stacked to about 5.75inches you will need,
primary, 148 turns #13AWG copper wire,
secondary, 4coils quafillar wound 25turns #12AWG copper
note that i use american standard gauge, i know that in India, the British system is used, so make adjustment to suit your local conditions...
i based my computations on the assumption that you will be using the cheaper non grain oriented steel......
hi tony thank u for the reply.
i searched and i found 2 into 3inch bobbin maximum so is this ok for 20ampere if not is this suitable for 10ampere, then can u tell me what is the winding turns of this and the guage.
thanks.
by the quality of the core on hand......
IME, there are 2 kinds, the GOSS steel will have a thickness of laminates at 0.35mm in general.....the non GOSS will have 0.5mm laminate thickness...
for the thin laminates i use 1T ~ 1.2T....
for the thick laminates i use 0.6T ~ 0.9T...
higher flux densities need fewer turns, so for a given winding space you can use fewer turns which allows you to use bigger sized wires and so therefore you can extract more power because losses will be lower....
I need a power transformer for H900 80-40-0-40-80 V / 15A to 20A. Boss Tony, is it possible for you to make 2 units for me? How much will it cost? PM me pls..
Thanks and God Bless
regards,
John L.
you can reach me 628-2996......
that will work also.....i am curious to find out the quality of laminates you will use, what is the thickness?
if you can tell me we can make adjustments...
are you sure? this is the first time i hear such material......do you have manufacturer's data sheets on your laminates?
of course you can....in my designs i go for low magnetizing currents, that is why i go for low teslas....
are you sure? this is the first time i hear such material......do you have manufacturer's data sheets on your laminates?
0.1 mm is well known material; meant for 400 Hz applications (power supply for planes for instance where weight matters).
Not well suited for a 50/60 Hz power supply transformer because the max T at those frequencies will be very low.
However you might use it for a very good output transformer.
does that mean you can assume a high Tesla compatible steel. Then check that assumption by measuring the primary loss.
If the guess was wrong then add more turns.Is that an acceptable procedure if one does not know what steel has been used for the core nor does one know the maximum Tesla suitable for that core?
When laminates are 0,35 mm you probably deal with good quality (corn oriented) M6; stay under 1,5T.
When laminates are 0,5 mm it is definetely one of the lower grades; stay under 1T.
How does one measure the thickness of the lamination in a toroid when it is completely hidden from view?
How can one be sure that 1T and 1.5T are the best performance targets for the two thicknesses that you quote?
What if the thickness is other than the two you quote.
I am trying to find a method that is fairly simple that can confirm that the correct number of turns have been wound onto the core.
How can one be sure that 1T and 1.5T are the best performance targets for the two thicknesses that you quote?
What if the thickness is other than the two you quote.
I am trying to find a method that is fairly simple that can confirm that the correct number of turns have been wound onto the core.
By removing the copper and insulation
Not "the best performance targets", but mere guidelines based on properties of the materials.
Let us know when it is different.
My calculations are based on sheets for the specific materials provided by the manufacturer, in my case specifically for c-cores.
Maybe you can find data for toroidal cores as well searching the net.
I am reluctantly repeating my question and the first reponse to it.
Your specific cases do not get me any closer to an answer.
Hi AndrewT,
Chapter5 of RDH4 gives a lot of answers........you can read it and find out....
designing transformers, you will find that calculating the primary turns, you may get a figure say 200, but when computing for the number of turns per layer, and number of layers, you will realize that you actually end up with say 220, or even 180......what i a m saying is that it takes practice to know these things....
pieter t said it eloquently,
again, pieter t put it as
i tend to go lower than these guidelines, these are choices designers make, we can not teach you how to make those choices, you have to find it out on your own....
making diy traffos, i am not constrained by cost.....
it all boils down to designing traffos that you are happy about the losses therein....
Chapter5 of RDH4 gives a lot of answers........you can read it and find out....
designing transformers, you will find that calculating the primary turns, you may get a figure say 200, but when computing for the number of turns per layer, and number of layers, you will realize that you actually end up with say 220, or even 180......what i a m saying is that it takes practice to know these things....
pieter t said it eloquently,
again, pieter t put it as
i tend to go lower than these guidelines, these are choices designers make, we can not teach you how to make those choices, you have to find it out on your own....
making diy traffos, i am not constrained by cost.....
it all boils down to designing traffos that you are happy about the losses therein....
Andrew,
Look at Transformers for some pretty good information.
Standard toroids are generally wound with 1,6-1,8T, using 0,35mm corn oriented cores.
When you know the number of primary turns, doubling that number would halve B max, or whatever you want in between. This is a linear function.
Look at Transformers for some pretty good information.
Standard toroids are generally wound with 1,6-1,8T, using 0,35mm corn oriented cores.
When you know the number of primary turns, doubling that number would halve B max, or whatever you want in between. This is a linear function.
Tony, thanks. I have read a few of the previous references you have provided.
I do take the point that one calculates or estimates the primary turns.
That I accept is not the end of the primary design.
I am looking for what comes next.
Checking that the primary turns has been correctly estimated. That is where your experience comes in could it be that the required turns needs to be adjusted +-10%?
I and all the other Members trying to learn from you need to be able to replace "your experience" with a method that shows we have it right or shows how much we have estimated wrongly.
That's why I ask for a measurment/test method so that we don't stop after the first guess and know what direction to adjust our guess to get the performance we are trying to design in.
Peter,
taking a blanket statement of 0.35mm use <1.5T, or 0.5mm use <1.0T, or toroid between 1.6T & 1.8T, gets me no where to wards knowing I have got the primary turns correct.
Read my reply to Peter and maybe you will better understand why and what I am asking.
ps, I read Tommy's paper, or an earlier version of it, about 10years ago.
I do take the point that one calculates or estimates the primary turns.
That I accept is not the end of the primary design.
I am looking for what comes next.
Checking that the primary turns has been correctly estimated. That is where your experience comes in could it be that the required turns needs to be adjusted +-10%?
I and all the other Members trying to learn from you need to be able to replace "your experience" with a method that shows we have it right or shows how much we have estimated wrongly.
That's why I ask for a measurment/test method so that we don't stop after the first guess and know what direction to adjust our guess to get the performance we are trying to design in.
Peter,
taking a blanket statement of 0.35mm use <1.5T, or 0.5mm use <1.0T, or toroid between 1.6T & 1.8T, gets me no where to wards knowing I have got the primary turns correct.
Read my reply to Peter and maybe you will better understand why and what I am asking.
ps, I read Tommy's paper, or an earlier version of it, about 10years ago.
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It is not so difficult.
Important is to know:
1. what core material you have there;
2. count the number of primary windings;
3. primary (line) voltage.
Then you can easily calculate B max, and change it when you want.