How to Design Your Own Inverter Transformer

please transformer laminations are very scarce to get, I checked online to purchase for 5Kva, their minimum quantity is in 100kg to 1 tonnes. please sir is there any guide?

please I need a 2000Watt transformer with the following v
alues: Primary:18V-18V,12V center tap, Secondary:600V,230V-0V ,12V-0V

Please can I wind the inverter transformer 350vac? Thanks sir

Hello sir, please how can I use 1 single transformer with secondary output with 8 ends to charge a 4 battery sets in series, 48v. I want to use the trafo to charge the batteries individually not as a whole.

Hi!
I would like to buy a 72V VDC transformer for 72v Li-ion battery to 220VAC on 15kw. Where Output 220VAC 50Hz on 80 Amperes if it can be done, and input VDC 72V with a few Amperes to connect the battery to it. So I need an inverter transformer, capable of powering 2x 4000 watt server computer power supplies that will have 16 Amperes each. Does this transformer work in your opinion? Or should I buy a 220V VDC transformer?.

Hello sir, for experiment purpose, is it possible to build a 80v input transformer to 12v output, Stepdown

If I use double 15awg wire in primary will it work? Current rating will increase?

Thanks a lot

Please help me, I want to build a 66-84v(72) 1500w, H-bridge inverter, how can I select the quantity of MOSFET to design the inverter, thank you

Can I use microwave transformer as inverter transformer?

Please kindly assist me in producing my mini inverter that can power my home appliances up to 220v in AC.

Please I need help I have a toroidal iron core transformer I want to use and design inverter transformer frequency is 50Hz the core dimensions are: OD=16.8cm, ID= 7.6cm and H=10cm how do I calculate the power of the transformer, core area and turn per volt.

Thanks

I’m confuse on inverter transformer and stabilizer transformer my challenge is that can I use stabilizer transformer core to design inverter transformer I have an 8kva stabilizer transformer core ring type can I use it to design inverter transformer of 7.5kva/72v.

Hello! How much Ampere should I use when using a power inverter that is 1000 watts? Lets say, is it sufficient or safe to use a 30 or 50 amperes of transformer?

I think in an inverter design the transformer primary voltage should less than the rated battery voltage or the secondary voltage should be little higher than the rated output voltage.
Another thing I want to ask you my brother is:
At what input voltage rating Will a transformer used in a 12volt pure sine wave inverter will be, is’t 7volt or 13-14volt will the transformer input voltage be?
Thanks in advance.

It is very helpful

Hello Swagtam. Please can I get the full table A and B chart. I need a current rating for 30Amps wire.

Please what guage for small step down transformer should I use for AC supply of 110v 50mA,

Greetings Swagatam, thanks for your informative site. Where the transformer is the load in a H bridge inverter circuit and the DC is a 12volt battery, what should the primary winding voltage be? The inverter is a 1000w 220v output and all the mosfets are blown.

Pls can u recommend any textbook about dese transformer equations u used.

Hi, I can’t calculate this: “First we need to find the core area CA = 1.152 ×√ 24 × 10 = 18 sq.cm”
For me the result is = 56,463

sir please how can i use 5kva stabilizer transformer as a center tap transformer for my inverter

Input&Output, Primary&Secondary depend on the ‘function’ the transformer (tr) is performing:

Inverter/Step-up (I) mode Or Battery Charging/Step-down mode (C).

Normally, Primary refers to Input side, while secondary refers to Output side.

The data in hand are:

Secondary Voltage = 230 Volts,
Primary Current (Output Current) = 10 Amps.
Primary Voltage (Output Voltage) = 12-0-12 volts, that is equal to 24 volts.
Output Frequency = 50 Hz

In the above, the Inverter mode is assumed, so Secondary/Output = 230 Volts.
Then primary I, and V should be Input and not Output, IMO.

Though understood, better to include a #Definition/assumption statement – Inverter Mode.

Hello,

Googled and located your site. Gr8 design info on how to build an inverter from scratch. I did BE EEE 40 years back, don’t remember any theory now, nor practically worked on inverter or any other circuit design.

Here is my silly basic query:

My old squarewave 750VA, 24V (2*12v battery in series) inverter’s MOSFETs burnt.
I think the copper transformer is intact.
I want to use the transformer and convert it to a 12V sinewave inverter, by replacing both the existing boards.
Is it possible?
If yes, where can I buy the rquired switching circuit board.
Thanks

How to make 1250VA 1000 watt 260v _12v ups transformer ?

Good day Sir, please what wire gauges for 2.5kva primary and secondary?

I used gauge 13 whose amp capacity is 8.6 but while charging the 16amps Circuitbreaker trip off until I used 25amps breaker, why?

Good day Sir, please I want to learn how I can wind a transformer coil with secondary coil connected to another joule thief transformer

Can the above core area, turns per volt formula work extremely well with ordinary iron core transformer?

Hello sir , thanks so much for the detailed information and teaching. I haven’t make any transformer before, but want to have it a try , hoping that the information gotten will be of help. in the transformer you divided 120/12 = 10amp, my question is if is 500w, should I divide it by 12 , using what I got as my amp ? Sir

Good day Mr Swag, thanks so much for your surport. Pls I have an issue below.
Having rewind my 200watt stepdown trafo to 200watt trafo center tapped with the above info trafo winding, which I got TPV @ 1.7v/v.
1.7 *230= 391 turns
1.7* 240=408 turns
1.7*8=13.6 for 8-0-8
Sir the isue now is once I plug it for testing it will draw or dim the light, which may show it is drawing current. I don’t know what to do.
Please sir any advice?

Good day sir, please how true is this notion? that any transformer can be designed using this formula
42/CA which will give TPV multiply by the voltagate of both primary and secondary to know the number of turns? That 42 is constant and does not change.

Please sir I also have this stepdown converter transformer 300watt and I want to rewind the transformer to centre taped. Pls will the capacity be upto 300watt after rewinding?
Will it work as a transformer for small inverter.

So when calculating for secondary current which of the output voltage do I use,is it the 120v, 230v or 300v ?

How about designing the transformer to get multiple outputs like:909 to 120v ,230v ,300v

Plz sir, one more question, if i’m to convert the transformer to 500w should i calculate the TPV for the new transformer wattage using the core area of the transormer

Thanks

I mean rewinding it to get 9-0-9v to 230v,500w transformer

Hi Mr swag thanks for your nice s,but I have a pretty little problem,how can I convert my old 1000w voltage stabilizer transformer to get a 9-0-9v to230v,500w inverter transformer without changing the core,I will be fine with a quick response.

Very nice explanation Sir. Thanks.

I have a transformer out of a old cnc control very heavy puts out 38vdc and 18vdc could that be used im not sure what there called its round rather than square

I am building an inverter of 12v and I just remembered I have an old UPS sitting around. The UPS is 24v, has 2 batteries. The transformer has 29.5v, 15v 0 15v in the secondary and 255v, 220v, 185v and 0v in the primary. I was wondering if i could use it for a 12v inverter since i was able to get 12v 0 12v in the secondary when i used 255v wires on 230v. Can I use it to invert the 12 from the inverter back to 230v?

How can I use this transformer for a 12v inverter?

thank you again

joe

Thanks for sharing your wisdom and experience with us!
I’m considering purchase of one of the chinese such as

Two questions. I’d like to use a toroidal core to wind a 240vac on a center tap secondary. The idea will be to do a 240-120-120-240vac split for use in North America (Canada specifically). Have you done a tutorial on specifications for a toroidal step up transformer (I plan on active cooling of the transformer to increase power capacity so windings would need to be for higher current ratings than typical for the core)

Second question: Thoughts on how to increase the rating of this board? IE mosfet banks to increase capacity. Would IGBT’s be a better choice?

Thanks again,
Doug

Dear sir,
Please sir, what determines the power rating of an inverter?

2. Please sir, for the Elite600VA pro UPS, does it mean that the UPS transformer is 600VA which can deliver a Max output of 360W?

Dear sir, please sir I have got a UPS transformer with center tap 7-0-7V/165-275V and also 16V winding for battery charging from Mercury Elite600VA Pro UPS

Please sir I want to check the current rating on the 7-0-7V winding using the shunt resistor method you told me.
1. Please sir should I connect the resistor across 7V or 14V?
2. Please sir the resistor I want to use as shunt is 0.1ohms 5W. Please sir is it Ok?

Dear sir, please sir I want to know how to measure the following from the core without using formulas, because I have a UPS transformer I want to disassemble and rewind based on calculations for use in the pure sine wave inverter circuit you designed.
Thank you.
1. Core area(CA)
2. Tongue width
3. Stack height
4. Window area
Please sir, include a diagram showing the four dimensions.
Thank you

Dear sir, please am confused here:
You said “simply dividing 120 by 12 gives 10 Amps, this becomes the required SECONDARY CURRENT”
But you calculated secondary current again from this:
Step#3: Calculating SECONDARY CURRENT = 24 × 10 / 230 × 0.9 (assumed efficiency) = 1.15 Amps.
Please sir my question is:
1. I don’t understand what the required 10A and the calculated 1.15A for secondary current mean.
2. You said again: “Now, the required Primary current is 10 Amps”
Does this mean that for a 9-0-9v, 10A transformer, the primary and secondary currents are 10A at full load?
Please sir put me through, I just want to get the difference , and be clarified.
Thank you

Please sir I want to know how to construct an inverter circuit and transformer that can carry big load AC.
I don’t know whether converting dc-dc and DC to AC is making inverter to have power to carry load.
Please I need help from you, answer base on your level of understanding to my level also.
Thank you sir

Good day Sir Swagatam, please how can I prevent my inverter transformer from getting hot and loud sound while on freezer. Thanks.

Hi,
Thanks for this article. I have a question regarding the frequency used in the calculation.

Imagine if we try to make a pure sine wave inverter using SPWM where PWM frequency is about 60khz. But the sine wave frequency is 50Hz. The 60khz SPWM will be fed directly to transformers primary through mosfets and the secondary of the transformer will be connected to a capacitor to filter out 60khz high frequency.

In this setup, should the frequency used for transformer calculation be 50hz (output frequency) or 60khz (input pwm frequency)?

Hi Swag, I enjoy your articles. Where is a good online source for cores and bobbins suitable for these projects, preferably in the US?
Thanks

Hey Swagatam,
I have an old 100 amps, 220/45 volts welding transformer. I wanted to know if I could use this transformer to make an inverter of 5000 w with 48 v input and 220 v output. I also have 4, 12 v batteries, 100 amps each for this purpose.
Thanks.

Can I use irf3205 to make 5000w inverter

Hi Swagatam, for this 120va inverter trafo design, primary current is 10A for 12v, but for sec current you did 24*10/230*0.9=1.15A, why not use 12 instead of 24. With 120A capacity the corresponding will be 0.58A for 230v( current capacity for sec side). Please help me to clarify my confusion. Thanks

Hi swagatam, please i want you to post me H-Bridge circuit diagram using irf740 for inverter and i need correct circuit. Thank u

Informative article, just what I was looking for.

Good day mr Swag, pls ist possible to use the above formula to build 2.5kva inverter even if we can not find the swg in the table.

Good day sir Mr Swag.
pls sir for example I calculated my TPV to be 0.8, now should I aproximate it to 1.7?

Please Sir, what is the difference between Turns Per Volt (TPV) and Volt Per Turn (VPT)?

Please for inverter design which Primary voltage is the best for 12v battery for modified sine inverter some say 10.5, 11v and 12v to calculate for number of turns

Hello sir, please what value of Es will I use to calculate the number of turns for the secondary of a trafo based 12v battery. Is it 12 or 14.4 to get the desired charging voltage after rectification. Thanks Swag

Hello Swagatam,

A great and wonderful work you’ve been doing. God bless you real good.
Can this transformer design be used for the sine wave inverter you updated here: https://www.homemade-circuits.com/sinewave-ups-circuit-using-pic16f72?

Hi swagatam,my name is ibrahim from Nigeria i would like to thank you for the detailed explanation of transformer design,may God reward you.sir ive gone through the calculations which are very clear to me my only problem is i want to design a 1kv inverter transformer i dont have problem with the calculations but the table. Can you please help me with a table chart that can handle upto 100amp? thanks and God bless

hello sir, I hope you are doing well and how is your work? sir, I thank you for the automatic cut off voltage regulator circuit which you send it to me in a couple of some days back. sir, this time I I need your advice. I am a Nigerian, from TARABA state.sir,between electronics and power or electrical, which one is more better to study so that one can be easily self reliance and he shall be accepted quickly when looking for a government work. the reason behind my question is that, I’m a student from mautech Yola university, and we just resume to run the first semester 300level.so,we are ask by the University to choose one in between the two to follow. although, I read electronics during my technical secondary school.

hi sir, I can stop thanking you. please sir, can I get one of inverter circuit and a cut off voltage circuit I.e,when the battery full, will stop it from charging and when it’s run down a little, like 10 percent out it will get it back to charging. please sir, that is my email. (emmygangba@gmail.com).

hello sir, I’m still thinking you. sir you said my battery voltage is lower than the transformer ratting, please sir can I have explanation of how your know the transformer rating.

hello sir, thank you for the reply! the load I used was one bulb and my phone charger,thou it is charging the phone well, but when I connect the supply wire to the battery, the supply wire started getting hot as well with the two mosfet. so, the battery ratting is 62Ah.i have tested the transformer according to step down, just as you said, the voltage spec I got was 15v

hello sir,good evening.my name is John,i constricted inverter using 12v battery and then I used a transformer from my old transformer, Thau, I don’t know the wattage of the transformer but it still works. so, my question is that, the two irf150 mosfet from my circuit are getting hort.pleace sir what is the problem?

Hi Swag,
I was trying every of your inverter circuits for experiment. but always most difficult part for me is find a current Transformer. and today I found two units of old Microwave oven transformers. and I have carefully remove the high voltage part. now I want to rewind both transformers one for 1000W inverter, other one for 500W inverter.
both transformers has to use in 12v to 220V 50hz inverters.
Kindly help me to rewind these transformers . what size coil and how many turns I have to wind.

Note:
please give some option to attache image while comment here.

Thanks and Regards.

Dear Swag,
i read this complete article. and i have something to clarify. nowadays i am always reading your website to learn and understand about inverters. and get ready all components except transformer. to try one by one just for experience.

from all this articles and almost all the diagrams available on internet about inverters i have understood something about inverter transformers but in real inverters has very different transformers and connections.

on your diagrams and articles
the inverter transformer is very heavy.
and it must have dual input for primary.
and the center tap of the transformer has to connect the Battery Positive line.
secondary line will be 220V direct output.
almost every inverter diagrams show like this.

now i have a fully working Chinese 300W inverter. i just open and see inside. it has very small transformer but its not giving direct 220V output. transformer has 3 pin out put and it connect to 4 IRF830 Mosfets. mosfets are giving output 220V

second
i just found 2 units of Damaged UPS form scrap shop. both are same brand and it has a very heavy transformer. but primary has only 2 pin instead of 3 pin. and The Battery Positive not connect to the transformer at all. Transformers primary 2 line connect to the heat sink of Mosfet( IRF3203)
(i cannot attach images here either i can show the pictures)

i am confuse with Inverter transformers. can you please explain me why the 300W inverter has small transformer and giving 300watts output.
and why second UPS has different kind of transformer.

Regards.

sir thanks for or response, I search for fly back converter but I didn’t find any but can boost converter work. I also came across or formular use in designing inverter transformer. now my question is as follows. (1) finding the core area you got 18sq.cm but accroding to my calculation I got 55.2 or am I missing something. Iike u said the core area is that centre E should the centre be reduce by width or height. (2) can u explain the word stack .(3) I didn’t understand No 16 & 17 calculation that is gross area & the tongue width .(4) what do u mean by total winding area . pls explain the word bobbin .pls don’t be angry with my question thanks.

thank you sir.so sir,which table can be used to build higher transformer, or is there any possible way for me to get the table from you,if possible, here is my email.emmygangba@gmail.com.

Turns Per Volt for 1000 watt Tranformer

Hello sir, I’m sorry to disturb,good morning .i calculate my own turn per volt using 1000w I got 0.66.so,during dividing the 1000w by the primary voltage 12v,i then got my primary current as 83.3amp.so,my question is that, I match it from the table A, to get the equivalent thickneas of wire but there is nothing like 83.3amp,from the table A, what am seeing is only 10.961 no 83.3.i.e,the rest is 1 figure before the decimal point not 2 figure before the decimal point, so, I’m confused to know my equivalent thickness of copper wire.

I thank you sir,may God continue to bless you abundantly.

please sir,what I mean is that.for example, I like to use a 1000va or 2000va or any watt of stabilizer transformer, can it work and can I going to divide the watt by the primary voltage to get my primary current as per the shown example specification.(2)i build one circuit is using a 12v battery and I get 220v output.so,if I put 100w bulb and my phone charger.then,the current from the bulb will start going down completely slowly until there will be no current show n from the bulb. what is the problem sir? (3)what type of battery should I use. although,i use a 12v generator battery of 7.6amps.(4)which side of the transformer will take the thicker gauge of wire, primary or secondary.

please sir, about the nick zuein inverter circuit of 2500 to 5000w,pmw,he use a jumper.can I be able to replace the jumper with ticker gauge wire or what should I use to replace it.

Please sir,do not be offended, I just want to be sure of what am doing.sir,for example ,I like to use a 1000va or 2000va or any watt of stabilizer transformer, can it work and am I going to divide the watt by the primary voltage,to get my primary current as per the shound example specifications.(2)i build one circuit,is using a 12v battery and I get 220v out put.so,when I put 100w bop and my handset charger,then the current from the bop started going down slowly until there will be no current should from the pop, what is the problem sir. (3)what type of battery should I going to use.although,i use a generator battery of 7.6amps.(4)wich side of the transformer will take the ticker gauge wire, primary or secondary.

Hi swagatam, my name t Emmanuel.please sir,i am trying to construct an inverter, I then enter net I found your explanation about how to get turns per volt, so my question is,the Tpv,i.e.1.96v that I sow,is he constant or I have to calculate my own.please sir, may God bless you as you replied back, thanks.

Sir pls one more question, cos i need ur help. In winding the the transformer, should i wind it according to an ordinary AC-DC transformer structure (primary separate and secondary separate then laminating them)? Or i should it according to a voltage stabilizer transformer whereby after winding the primary, the end terminal of the primary is joined with the starting terminal of the secondary winding, after winding the secondary with its center tap, the end terminal of the secondary with the starting terminal of the primary forms the two output as L and N mains. Sir i hope my question and explain are clear, help me because winding transformer is my field of day to day practical, i just want know in which manner inverter transformer constructed as i differenciated above. Pls help,Thanks

So now which side should have more number of turns?

Hello sir, i have few questions to ask pls help me:
1. I dont understand, u said divide 120va by 12v we get 10a, how does 120va come about, am confused.
2. Which of the transformer is the battery side, primary or secondary?
3. Which side of of the transformer contains thick wire, primary or secondary?. Pls help, thanks.

Tnx u used the word primary and secondary side interchangeably,
Is it not correct to call d 12v battery side as primary side as against ur usage sir..
Am confused with that,
Secondly, if I fabricate my lamination (E/I) core.
Will i need to apply any luvrixant/paint..
Tnx.

Which calculation to look for bobbin size?

Why we need to consider efficiency while calculating primary current and we didn’t consider efficiency while calculating secondary current

thanks sir…please help with circuit diagram of power supply using chopper coil such as 6v DC output from 230v ac input

engineer Swagatam good morning sir thanks very much for ur effort to help us…I made ur circuit.. and it worked normal but when I power my TV the inverter will in drop and come up gradually… pls help….

nice God bless you.

Hi Swagatam,

I going to a professional transformer winding person after two days to get my 1kva inverter transformer (center tapped). I need your help. What specs should I ask him?

should it stepdown or up?
what should be primary voltage and current?
what should be secondary voltage and current?

thanks.

Hello Swagatam, Long time ago I'm now back since I was making LED with you. Now asking for your help about the transformers build home made spot weld. I have many Microwave transformers but this time I have large rectangular laminated iron core made by Honeywell was using for old military scanner. This old transformer is larger than other MOT I have. So removed old copper wires and saved for later used. It was tested connect input 120 VAC and output multi-Low voltage from 5 to 24 volt AC. So now left it down to bare iron cord clean up small amount of rust area and ready to add hi temp paint. Now, however, I'm not good on math formula to put wire wrap number of turn of 5" long X 2.625" W X 1" plus thick for primary for 120 VAC. The core measure outside dimensions is 7.1875" long X 2.4375 deep X 3.4375" height. Output Secondary using 0/4 wire welding cable possibly 2 or 3 turns would be less that 2 VAC which may be high amp.

I know I see you don't deal with Transformer Calculation I read on your post.
If all else to give me number of turns for 120 VAC for primary and size of wire gauge recommendations.
So the electronic math formulation is complication as I read about which I'm confused!
So I explained above about the iron cord is laminated rectangular with round edges outside corner with opening
square rectangular inside dimension is 5.25" X 1.5". I was not able to add picture in this post to let you see.

Please let me know if you know someone read my post.

Thanks again,
John Hungerford
Deafguy

hello dear swagatanm
i would like to ask you if an inverter output is 24v and i need 220 v for my home supply the creation of my toroidal transformer i have to create first the 24v winding as primary and then the winding of the 220v because in the toroidal transformer the one is on top of the other
also i have a swg table that says the curent the diameter the gauge of the wire if you wish me to send it to you thank again for your help

Pls sir help me out. I can't understand where you got these values "CA = 1.152 ×√ 24 × 10 = 18 sq.cm
We select CRGO as the core material" and the meaning of CRGO. Pls if you can upload the picture of the core of the transformer you measured maybe that will help me understand it better. Thanks

Am Andrews Kumah

Pls sir help me out,what I don't understand in your calculations is this "CA = 1.152 ×√ 24 × 10 = 18 sq.cm
We select CRGO as the core materia". That is, I don't understand where you got the values and also the meaning of CRGO.
ALSO I THINK EVERYTHING WILL BE EASY IF YOU UPLOAD THE PICTURE OF THE CORE YOU MEASURED

Hi sir, I tried calculating the specs for a 5kva inverter transformer using 48v dc supply,freq.50hz, output voltage 220 but what I get as the amperes is out of the table so I could not determine the wire gauge.the highest ampere on the table is 16.6. Can you help me out sir please if possible with the specs. My email. mrzakson@gmail.com. Thanks

hello.
our sg3525 inveter when i move the pwm verible so the pin1 vollatge is also chnage so plz tell what is problem in our inveter pin1 i connect with pin9
regard
baber khan charsadwal

sir what is 42 as constant in transformer design means ? How does that constant forms ? I am giving one example of a transformer design in the link given below in which the transformer design uses that constant..

i had a 300 W step down transformer with 5 primary terminals and 4 secondary terminals…. i have deassembled the transformer and done the primary winding part… i have the following doubts .. please clarify those…
(1). According to the video

the area of the core portion is
6.3×3.4=21.42

so no. of turns per volt =
42 constant/21.42 = approx. 1.96…

hence no. of primary windings needed = 230 × 1.96 = 450.8 = 451 turns

and no. of secondary needed = 16 V × 1.96 =31.36

Are these calculations are correct ? Should i have to select 240 instead of 230 in calculation which will result in increase in no. of primary turns…

(2). Which configuration of secondary will be better a centre tapped one or with one normal possitive and grnd configuration ?

(3). how to take 32 V output from the centre tapped config. ?

dear brother
I want to make a 800-1000w transformer for ips. I have bought all component to make it.
here is the list.
CABLE:-
SWG 21 for primary winding,
SWG 12 for secondary winding,
CORE:-
4.5 inch
FORMER/bubbin:-
3.05"/7.747c.m.
1.6"/4.064c.m.
The transformer is make by 12-0-12V secondry and 0/N-140-220-260V
Plz help me to find out how many turn will be in primary winding and secondary winding

Hello Sir

Sorry of asking you again.But I want to know how to make mains transformer with using Toroidal core.I attach Core image and core manufacturer Test certificate. Can you please help me with that information i providw core size is OD-100mm, ID- 60mm and Height-50mm core wet about 1.842 KG (M4 CRGO material)
https://drive.google.com/file/d/0B5ROBprWe44vYnBURUt0MVNxTkdSRXFqUjhuWHpBUFg5X1Nv/view?usp=sharing
https://drive.google.com/file/d/0B5ROBprWe44vODRxUGo4cE9TcEE/view?usp=sharing

Hey! I've a ques about 12v battery inverter that can we use 15-0-15 transformer instead of 12-0-12 ?? will it work ??

Sir ihave 500 watt inverter please sir transformer primary and secondary turns and bubbin size send my email ma2604403@gmail.com

Hello Sir. I am amateur in this field. I want to design a Transformer or a circuit that produce 12v 30am that control my DC motor. Or

Sir I have 12kva automatic voltage stabilizer 50 to 220v make sir please their turns and bubain size tell me

Thanks sir
And please tell me how to make 100W dummy load for testing transformer secondary voltage and current.
and tell me if my transformer is 22-0-22/3A=132VA if i used single 0-22 out its current is 6A or 3A and with 0-44 current should be 3A or what i am bit confused.

Thanks Sir
How to check Transformer secondary maximum voltage & current through dummy load
for example if I have step down transformer with 22-0-22 Vac/3A=132VA how to check this with loaded out please give details.

Is your SWG table is accurate.Because to many on online. can I design transformer with Constant 42 for example 42/18 =2.33 turn per volt

Calculating Gross Area we get = 18 / 0.9 = 20 sq.cm
my doubt is 0.9 is constant value or how did you got this value. thanks in advance

Hi, tried to comment before but don't think it worked. My question is- can I use a toroidal transformer in a push pull configuration? I have seen a 300va 115v/230v to 12v toroidal. It's a dual primary dual secondary wound transformer. If this is possible am I right in assuming I will only be able to use it at 230v at 150va?

Hi i am wondering wether it is possible to build an inverter with a toroidal transformer. I have seen a dual input dual output 115/230v to 12v at 300va that is 2 times 12v at 150va each. Would this work via the push pull circuit.? Any advice is much appreciated. I'm assuming if it is possible I would only be able to use it at half its rates output of 150va at 230v

Helo sir,
I want make 230v to 120v 1500watts step down transformer,how will calculate,SWG of primary and secondary,and number of turns,primary's and secondary's.please send details to my mail eeemani09@yahoo.com.

Plz reply to all queries immediate, Thank you

Sir, A mechanic told me that a transformer has a number of different-different size,please tell me about this

Also tell me sir,why did you multiply total winding area to 1.3 ,and what is insulation part,and why you multiplied, why not you added it?

I am not getting understand that how to understand about winding area,ssuppose I completed total no. of turns, but how to know that this winding area will match to calculated winding area?

Hello sir,please tell me how to calculate the bobbin size?Also tell me,which windinds should be inner side or outer side?

Hello sir,plz tell me which type of area in sence that primary and secondry winding area are to be maitained,i.e circular,cylindrical or other types?please tell me

Hello sir,this is Abdus, plz show me in figure where is core area part?

Ok. I will try them out practically, and
I will get back to you. Thanks.

Hello Swagatam, My name is Tobi. Thanks for the tutorials. I'm an Electrical/Electronic Engineering student and I love electronics so much. I've been trying to design an inverter of 100watts or more, just for my personal use. I've seen a lot of inverter circuits on google and youtube but each time I simulate them on my circuit wizard software, they don't work properly. So please can you help me out with a cool circuit that works fine or give me a link or something. I'm very good with theories but I want to be good with practicals as well. Please I really need your help. Thank you.

Hello boss! Hope everything is going smoothly. Am sorry I promised to notify you(7,dec.2013). The circuit(oscillator,power stage) worked,and I have been using it, thanks once again,it was because of your assistance,I sincerely appreciate. Can I connect two identical transformers in parallel (center taped) to my inverter? My aim is to multiply the wattage. Extend my regards to your family.***Ahmed***4rm*****NIGERIA*****

Dear Sir,

Thanks for such a good document, sir I required 50W transformer for 12V system. So, please help me out.

Where did you get the (0.9) when calculating the primary current?

how to make 1000 w transformer from above method

Dear Sir ,what do we mean by the primary and secondary winding area and what is its significance while winding?

right answer is
1/(4.44*10^-4*18*1.3*50=1.925 not 1.96

Can I use Ferrite core for 50 Hz inverter transformer?
If yes give winding details for a 9-0-9 / 230 volt 500 VA transformer

Hai Sir good morning,
Last week I went to a local transformer/inverter maker for a 800 watt 12-0-12 transformer for an inverter project,he said the primary will be 21 gauge and secondary will be 12 gauge,because of his reputation for supplying good inverters I gave the order for the transformer.as per above calculation 800 watt/12 volt is 66 amp but the chart is saying 12 gauge can carry only 10amp.He is giving a surety that it will carry 800 watt load.What is the trick they are using.

Hi sir,
In calculating turns per volt, Is the 1.3 a constant no? Does this refers to the magnetic flux density or the saturation of the core?

sir,
the article is really interesting. In order to design a distribution transformer, will the core designing be same as sir has done? Or is there any difference? if so, i would like to request your kindness to elaborate on it.
Thanks

Thanks for ur reply that surelly works

Pls I will like to know the type of transformer that can be used for 1kva inverter and also the rating of the transformer. Thanks

Thank you sir for replying,, actually I am stuck with giving the time delay for the igbt switches in a dual half bridge inverter config. Its for simulation purpose….. because of the dual config. m always getting wrong o/p. please suggest anything.

Hi Swagatam,
Can you please help me build a 200amp inverter.

Thanks for your reply,I don't know any professional online but pls if you know one, kindly link me to him

Pls sir. I want you to help me with the calculation for 1kva transformer inverter. I used the above method but the challenges was that I couldn't find the wire thickness from the table you gave above. Please I will be very grateful if u can upload a table that will start from 1 and not 10 for both thickness and lamination. Or if there is another way of doing the calculation let me know sir. Hope to read from you soon.

I really appreciate your tremendous effort in help others out. Please sir, I want you to help me calculate the core size for the primary and the secondary, number of turns, the lamination size for 1kva transformer for inverter. I tried using the method you used above but I halted when it comes to choosing thickness of wire for the secondary in the table because I couldn't find there. Please sir. I want you to give me the wire table that starts from 1 and not 10 and also that of lamination table. I had be very grateful if you do that for me sir. Hope to read from you soon sir.

i have an 200watt inverter with two irfz44n mosfets. how can i increase its power to 400watt.? can i add more mosfets in parallel? plz reply soon.

Hai Sir,
For secondary winding should we double the turns that is 49 centre tap 49 total 98 turns or after 24 turns should we take the centre tap and again wind another 24 turns.

Please do design a 5Kwatt inverter transformer.

this will be much more needed since we are all globally going for green energy. And 5kwatt inverter is much sought after, than low power inverter.

I know but where do i connect the power supply for the fan?