DC to AC Inverter - Build or Buy?

Discussion in 'General Electronics Chat' started by Joster, Jun 12, 2013.

  1. Joster

    Thread Starter Member

    Jun 12, 2013
    Hi All,

    I have seen many schematics of inverters, I assume mostly non-sinusoidal, and I would think I could do this significantly cheaper than buying one. All I need is a 60Hz square wave, power section, and transformer. I figure I could build any size I require simply by using the right amount of say, parallel MOSFETS and a suitable transformer. The FET's aren't too expensive and I have tons of salvaged transformers.

    Also, about pure sine wave inverters. Could I not simply feed the power section with a 60Hz sine wave instead of a square wave? As long as I preserve the conditions for faithful amplification I should be ok or perhaps I'm missing something?

    Or should I just stop here and buy one?

    Thanks for you help!

  2. gerty

    AAC Fanatic!

    Aug 30, 2007
    Check the prices on some of the parts you just mentioned....I don't think you can build one cheaper.
  3. crutschow


    Mar 14, 2008
    How much power do you want and do you want sinusoidal or not?
  4. KirkMc

    New Member

    Jun 12, 2013
    you did not state the amplitude of your square wave. if it is line voltage try an H bridge on a stack of batteries. That has low source impedance. Add some inductance in series to help soften the square waves. Normal transformer gear doesn't like the high frequencies in a square wave.
  5. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    Buy. Building will be several times the cost.
  6. JDT

    Well-Known Member

    Feb 12, 2009
    Buy! This is one of those things that looks easy - until you try it.

    Two rules:-

    • You get what you pay for. A good inverter will cost serious money.
    • Don't even think of getting more than 300 - 400W from a 12V battery.
  7. Joster

    Thread Starter Member

    Jun 12, 2013
    Thanks a ton for all the feed back everyone! Definitely got the info I need. I will be buying for sure.
  8. LDC3

    Active Member

    Apr 27, 2013
    This will be a moot point since you decided to buy an inverter.

    You would lose power when changing from a square wave to a sine wave since the maximum amplitude of the sine wave would be the same as the square wave. The power lost would be the difference between the 2 waves. And, as it was pointed out, a square wave would heat a transformer more than a sine wave would.