Modified Sine Wave vs. Pure Sine Wave

Discussion in 'The Projects Forum' started by wconant, Jun 29, 2012.

  1. wconant

    Thread Starter New Member

    Jun 27, 2012
    I'm hooking up my camper trailer and I am wondering which wave I should use.
    The only thing that I am worried about is the original refrigerator in it.
    It's a Marvel Model UL-40. Its says motor 1/8 H.P 115 V 60 CVC AC.

    So can someone tell me if they think that a Modified Sine Wave would work fine with the fridge?

  2. Wendy


    Mar 24, 2008
    I will refrain from closing this thread it you will refrain from open another thread on the same subject. All four of your threads (including the one that was closed) are asking things about the same subject 3 ways. Instead, stick with one thread and ask the questions there.

    Most AC inverters create square waves. Motors and light bulbs don't generally have a problem with this. What does have problems is recievers, because a square wave is loaded with harmonics (multiples of the core frequency) all the way into the RF spectrum.

    Your fridge will be fine.

    AC/DC Inverters
  3. wayneh


    Sep 9, 2010
    I'm not so sure that's true anymore, Bill, unless "most inverters" sold are also at the lowest price level (which could be!). I think a lot of inverters you'll find on the shelf have moved to the stairstep, or modified sine wave instead of a pure square wave. It's probably marketing driven, since they know the market is larger if they can make claims of wider application to laptops, TVs, etc..
  4. wconant

    Thread Starter New Member

    Jun 27, 2012
    I apologize.
    The first post, I realized I posted in the wrong forum and didn't know how to delete it.
    Then I thought that my diagram and what wave I'm using were two different ideas, so therefore two different posts.

    I see that they should be in the same.

    Thanks for your help.
    Last edited: Jun 29, 2012