http://www.interq.or.jp/japan/se-inoue/e_ckt30.htm

paste this link to your browser, you will see how to design a simple square wave inverter for your self. It is cheep and simple, to save money you can use ur stabilizer. Let me know, anything you don't understand. Sinewave is also available but complex. Squre wave is good to start with. Click on the beens collection to view the area. The power you want depends on the number of transistors you use

sorry the link I gave you was for SINEWAVE. This is for Square wave http://www.interq.or.jp/japan/se-inoue/e_ckt8.htm

Have you done this on your own Do you have a sample? Please get in touch, I need some coaching from you on this.

Yes of course, is very simple but squre wave. If you are not technical please do not try

Why wud u want to intentionally design a power supply that outputs a square wave?

I said I need some coaching on this, I mean Inverters generally. what are the differences, and what type is good for house hold use. Please advise!

Wrex, for you to really understand inverters needs a chat like yahoo chat mecussey@yahoo.com, but let me gist you small; we have True sinewave, Simulated sinewave and pure square wave. Square wave is the easiest and cheepest to build but list efficient, simulated sinewave is a modified square wave or a modified sinewave, it is also cheep compared with True sinewave, True sinewave is the best and costliest type of inverter and it can work with any of your equipment just like normal electric. Simulated sinewave is the most available in the market, cause its cheap, it works very well with normal electronics like TV etc but inductive loads like fans will take two times the power they take in a normal electric and tubes might have a buzz sound. Add me if you need more explainations

hi, MECUSSEY d site u posted is was showing erow thnks newton

Power inverter is a very useful device which can convert Low voltage from a DC source to high voltage AC. The most common power inverter is 12V to 240V inverter. Perhaps that is because 12V batteries are common. This type of power inverter usually draws current from a DC battery. This battery should be able to provide a high flow of electric current. Normally lead acid batteries can server this purpose well. This current is then converted to 240V square wave alternative current so that we may empower those electric appliances which work on 240V instead of 12V. Inverter falls in the category of expensive devices so many people don’t buy them even they need them. What if I tell you how to build an inverter yourself?

I remember when I build my first inverter, I was very happy and I invited a lot of friends to see my homemade inverter. I am sure you will feel the same. Before you start building this inverter circuit diagram, I want to mention that this circuit involves 240V and 500W which can be fatal. You should take all security precautions before building this circuit. Preferably use electricity protective gloves and try not to play with the inverter circuit when it is operational. You will need little to medium knowledge of electronics in order to build this circuit. Alright, let us get to work. There are a lot of inverter circuit diagrams available online;  [url=http://www.chinabuye.com/Buy China"] Buy China [/url] some of them are complex and others are low performance. I have researched on a lot of them but in the end, I designed my own inverter circuit which is comparable to any professionally made inverter but still is simple enough for you to try. Here is the inverter circuit diagram:
It took me less than $100 to complete this circuit.

You will need the following parts.

2 Resisters 470 Ohm ¼ Watt
3 Resisters 22 Ohm 1 Watt
1 Variable resister 10K
1 Capacitor1uf
1 Capacitor 220uf
1 Zener diode 8.2V
1 IC CD4047
1 IC 7809
1 Transformer 12+12/240 (500W)
2 Transistors D313
12 Power Transistors TIP35C (make two pairs of 6 transistors each connected in parallel)
2 Heat sinks to fit power transistors
Some wiring wire (for connections)
A wiro-board (To build circuit on)
A 12V battery of 12V power supply for testing purposes
There is only one variable resistance in this circuit diagram which is used to adjust frequency of 240V AC output current. You should have a frequency meter to adjust this frequency of 50HZ to 60HZ as per your requirement. Please do not power up any device with your inverter before frequency adjustment because a wrong AC frequency can burn your equipment as well as your inverter.

I have used a two stage regulated power supply to avoid frequency changes with the drop of battery voltage. First stage is 7809 which is a standalone voltage regulator. It converts 12V DC to 9V DC. Then we have used a 22 Ohm resistor and then a zener diode of 8.2V which forces current to stay at 8.2V. The 22 Ohm resistor is there just to aid zener diode. The output frequency of this inverter circuit is square wave so it is not best to power up inductive loads so use it at your own risk. However I do power up fans at home using this inverter and I never had any problems other than a little decrease in fan speed and addition of a little noise.

hello Hongwen,

I have a 3000w Inverter and i recently discovered it doesnt charge the battery (only inverts). I dont want to risk giving it to the technicians around here because they might damage it further and i love and enjoy it so much.

My question is this:
I have a separate battery charger i got recently the specs is 12volts, 6Amps. is this capacity ok to charge my 200AHS drycell battery? I have had experience in the past with chargers and i dont want to damage my battery.

Many thanks.

Its better to buy staright away that design.

pls i need advice i want an inverter for my cafe where i have 20 systems dat  runs with each v=115/230
A=3.0/1.5A
Hz=50/60
(cpu rating) each for 20 cpu   and monitor 0.5 A each  for 20 monitors 1 hp printer 5 orbit fans and and a music amplifier , i usually use a power generator of 3kva and it power everytin convinientlly what rate will be the rating of inverter i will be needing to power everytin at once (the wat and howmany 12v batteries will i need to power it)

wat's up, i needed help on how to configuer the pins regulator ic7809 to get the terminals needed ( both: input and output, then ground).peast it here or send to my mailbox , fcclement@yahoo.com [b][/b]

if the regulator is facing u,d input is at ur left,common at d middle and output at ur right hand side.

habumaks: hello Hongwen,

I have a 3000w Inverter and i recently discovered it doesnt charge the battery (only inverts). I dont want to risk giving it to the technicians around here because they might damage it further and i love and enjoy it so much.

My question is this:
I have a separate battery charger i got recently the specs is 12volts, 6Amps. is this capacity ok to charge my 200AHS drycell battery? I have had experience in the past with chargers and i dont want to damage my battery.

Many thanks.

the recomended charger for a 12v 200ahs should have this rating(14v 20A) for better results.

flames77: the recomended charger for a 12v 200ahs should have this rating(14v 20A) for better results.

inrespective of the charger you are using, it should be automatic tha is it should stop charging after fully charge

Can you charge the battery from the power produced by the inverter?

[quote author=Saib4Jesus][/quote]
you cannot charge the inverter battery as it is working, but you can used the output of inverter with 200ah to charge the type of small generation battery 7amp