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Issue with small AC generator

  1. Jul 17, 2010 #1
    Hi all,
    The country where I live, electricity outages are a part of life, so to compensate for it I have a small 2.2kW 220V AC generator in my house. The problem with it is that I've heard and found out for myself that its output is unfit for running electronics.

    Testing with a voltmeter, the output is a consistent 220V, however, whenever I turn on my PC on it the power supply makes a weird buzzing noise. Also, I have a UPS w/ surge protector that doesn't even go on charge mode when plugged in with the generator on i.e. it doesn't consider the output suitable enough. Many laptop repairers and computer technicians have also warned me not to charge laptops from small, single phase generators.

    So anyone have any idea what the problem might be, and more importantly any inexpensive way to get around it?

    Thanks in advance.
  2. jcsd
  3. Jul 17, 2010 #2
    Hi there "Gamefreak123"!
    Your computer power supply wants a pure sine wave, and what it is probably getting is full of harmonics.

    What model is your present generator, please?

    Unfortunately, higher harmonics in the mains supplied to the computer can cause glitches in the operation of the machine, and can also cause power supply failure.
    I have seen "true sine wave" converters, which produce nice clean mains power from 12V batteries.
    Such converters are cheaper this year than they were last year. This link might help: http://www.powerstream.com/in15t.htm
  4. Jul 17, 2010 #3
    *cough* some cheap Chinese one whose producer doesn't even have a website :D

    Yeah you're probably right. I was hoping that there would be some magical device which could fine tune the generator's output and make it suitable, but I guess there isn't any. In that case, should I just buy a pair of fresh batteries for my old UPS? Its an http://www.ablerex.com.sg/downloads/products/tearsheet1000.pdf" [Broken] a decent brand I think. You think its output would be good enough? It is pretty old.
    Last edited by a moderator: May 4, 2017
  5. Jul 17, 2010 #4
    It's probably OK.
    Although I cringe every time I see people use batteries.
    Last edited by a moderator: May 4, 2017
  6. Jul 18, 2010 #5
    I noticed Honda has been producing small generators with inverter outputs. These have excellent output characteristics, but would probably be too wimpy for larger appliances.
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