This should be so easy for one of you.

[Grapeape]

I’ve been working on a fun little project and I’ve run into a snag. I need someone who could easily make a little board for me. I need a part that I can’t find over the internet at the various part stores. It’s a 24vDc to 24vAc inverter. It has to be as small as possible. It also has to handle a 40 C (40Amp) burst of power.

Here is the 6VvDc to 12vAc version that handles about 2 to 3 Amps. It’s really small. My project will fry that thing though. I haven’t even tried to hook it up.

If you are the type of person who could do this in their sleep I’ll give you some cash for it. I would like to move this project along. I’m looking for someone who just likes to do things like this and would like to make some money on the side.

I have a picture of the small board I've found if you want to see it.

 

[blueroomelectronics]

What's the continuous power requirement? Is it 24VAC peak or RMS?

 

[KMoffett]

You should know that anytime someone says "This should be so easy"...It won't be!.

Here is the 6VvDc to 12vAc version that handles about 2 to 3 Amps. It’s really small. My project will fry that thing though. I haven’t even tried to hook it up.

Attachment???

What frequency of AC? How much current output when no burst? How long is the burst? How long between bursts? Is the load resistive, inductive, capacitive...?

"Inquiring minds want to know!"

Ken

 

[Grapeape]

Cool, Thanks for the replies!!!!

Blue Room - Love the southpark character...

Now that you asked the Min Vf is 17.4Vac the typ. Vf is 20.8Vac and the Max is 24.5Vac. I don't know if this means that its a sine wave or not because on the specs it is a square wave.

Hey Ken,

Your absolutly right. Things can get out of hand real fast and that is why I'm here. It just seems that a simple inverter curcuit 24 to 24 shouldn't be that difficult when there are so many out there. I just can't find one that handles 40 Amp burst. I am just thinking that one of you can beef up the basic curcuit.

Attachment meaning that I have a picture of a similar circuit that I've found and has worked on weaker units.

I'm assuming that the fequency is 60 but I can double check for you.

There is just one burst. It is maximum 20 seconds.

Is the load resistive, inductive, capacitive...? Where in the specs could I find that answer for you? I'm looking but there is a lot of information there.

Jim

 

[KMoffett]

Grapeape,

I guess the big question is, "to what is this inverter supplying power?". Can you post the schematic for what you have...and tell us a lot more about where you are getting specs like "Min Vf is 17.4Vac the typ. Vf is 20.8Vac and the Max is 24.5Vac." Too often people want help with "their" solution, but do not want to tell us what the "whole" problem is. There may be a better way. Help us help you.

Ken

 

[BaCaRdi]

OK I am lost already, not too hard to accomplish..hehe

Why do you need an inverter, Is it a square or sine wave you require?

Do you happen to have any schematic, drawing or anything?

You need to tell us what the load is before we can answer the question. Matter of fact that would be a question I would ask you..lol

Is there a coil? then it's inductive. You seem to need a nice MOSFET, SRC, a 60amp load is pretty high! So I can almost guess it's inductive.

Your looking at the data-sheet? why not attach a link to what you are reading Save time asking, when we can look ourselves.

EDIT: Ditto Ken
-BaC

Blue Room - Love the southpark character...

Now that you asked the Min Vf is 17.4Vac the typ. Vf is 20.8Vac and the Max is 24.5Vac. I don't know if this means that its a sine wave or not because on the specs it is a square wave.

***SNIP***
Jim

 

[Hero999]

A 24VAC squarewave from 24VDC is easy, just an oscillator driving an h-bridge.

A modified sinewave is slightly more complected, a boost converter to increase the voltage to 34V followed by a circuit to drive the h-bridge so it outputs a stepped waveform.

Sinewave is a lot more complected, you either use a class A-B amplifier after the boost converter which is inefficient or a class D amplifier which is more complected.

 

[Grapeape]

Rock on!

We're not doing anything complex. We are using off the shelf parts that just produce more juice.

We're assuming it's a 60Hz Sine wave due to the smaller example that we found.

If I sent you all the information I had on the two parts do you think you could build the Inverter for us?

 

[mneary]

We're not doing anything complex. We are using off the shelf parts that just produce more juice.

You need to increase the power?

 

[Papabravo]

Back of the envelope calculation

40 Amps * 24V = 960 Watts ≈ 1 kWatt
assuming 80% efficiency, 960 / .8 = 1200 Watts

I can tell you without fear of contradiction that any feasible solution will be neither small, nor cheap. At those power levels any cicuit you design and fabricate will require extreme care and attention to detail. I estimate the engineering cost for design and a handful of prototypes at between $12,000 and $18,000

 

[BaCaRdi]

Have to agree here.

Anyone could build it, it's the cost involved, engineering the design is the expensive part. Damn engineers make good money an hour, if not on salary already

-BaC

Back of the envelope calculation

40 Amps * 24V = 960 Watts ≈ 1 kWatt
assuming 80% efficiency, 960 / .8 = 1200 Watts

I can tell you without fear of contradiction that any feasible solution will be neither small, nor cheap. At those power levels any cicuit you design and fabricate will require extreme care and attention to detail. I estimate the engineering cost for design and a handful of prototypes at between $12,000 and $18,000