Connect with us

Portable Generator questions

Discussion in 'Electronic Basics' started by Eric R Snow, Dec 19, 2006.

Scroll to continue with content
  1. Eric R Snow

    Eric R Snow Guest

    Greetungs All,
    I have a small generator (700 watt, 850 surge) that I use to keep the
    fridge running when the power is out. It is a robust unit made by
    Robin and is at least 20 years old. It has an accurate analog
    voltmeter on it. I tested it by comparing to a digital meter and by
    directly connecting just the meter to the 115 volt, 60 Hz mains. The
    label says that the generator puts out 60 Hz but when checked with an
    oscilloscope (TEK 465B) it shows about 50 Hz. Even though the fridge
    seems to run fine it sounds different than when operating from the
    mains. The meter on it shows the voltage as being 115 volts and the
    motor is running at the nameplate RPM. So what could be the reason for
    the 'scope showing the lower Hz and is there anything I can do about
    it? This generator uses brushes on a slip ring to energize the field
    winding and has some type of transistorised voltage regulator.
    Eric R Snow
  2. Rich Grise

    Rich Grise Guest

    It might have come from Europe or something - doesn't it have a nameplate
    that tells you what the output freq. is _supposed_ to be?

    It might be as simple as an RPM adjust, since the voltage is regulated,
    but anyone here would need much more information about the unit itself;
    otherwise we'd just be guessing.

  3. Don Young

    Don Young Guest

    Small generators generally need to be adjusted so that the voltage and
    frequency are about 5 to 10 percent high with no load. Both will drop under
    load. I would try setting the engine speed up a bit. I would also suspect
    the oscilloscope calibration. The frequency cannot be incorrect when the
    engine speed is correct if it is a direct connected generator.

    Don Young
  4. Phil Allison

    Phil Allison Guest

    "Eric OR Snow"

    ** Test it with an electric clock or clock radio.

    See how much time the clock loses over a few minutes.

    ........ Phil
  5. James Beck

    James Beck Guest

    What would that accomplish above and beyond looking at the signal with
    an O'scope? I would think the scope would be the preferred method and
    the clock using the 60Hz as a timbase would be the "I a'int got no
    scope" option. If his O'scope showed about 50Hz I would think it is
    about 50Hz.

  6. To remove any doubt about the scope calibration, sync the scope
    horizontal sweep to commercial power, and look at the generator
    output. When the engine speed is correct, the waveform on the scope
    should be stable, or drifting very slowly one way or the other.
  7. Phil Allison

    Phil Allison Guest

    "James Beck"

    ** A scope trace may be out of calibration, maladjusted or misread.

    ** The clock method is vastly more precise and fool proof.

    ** Time to improve your thinking - fuckhead.

    ........ Phil
  8. Tom Biasi

    Tom Biasi Guest

    Take you medicine.
  9. Phil Allison

    Phil Allison Guest

    "Tom Biasi " = Jerk Off Scumbag

    Go choke on a dog turd - cuntbrain.
  10. me

    me Guest

    or look at the powerline frequency on the scope, if its ok then the other
    measurement is likely ok....
  11. Dave

    Dave Guest

    I'll have to remember these lines for those times when someone disagrees
    with something I say, maybe, at a party.

    You must hang with a tough crowd, Phil, or get beat up a lot. Or, and here
    is the real deal: with your undersize penis, skinny little chicken arms and
    receding hairline, you are too chickenshit to have this type of conversation
    with another real person, so you choose a medium to offend where there is
    virtually no likelihood of consequences. it's unfortunate for the rest of
    us that you're such an offensive and antisocial bastard, because what you
    say seems to have a degree of technical merit.

    So sad....

    Sorry for the rant, group.
  12. Phil Allison

    Phil Allison Guest

    "Dave the Asinine " MeToo" Fuckwit. "

    Go choke on a dog turd - cunthead.
  13. James Beck

    James Beck Guest

    May be yes, but it is the tool of choice and BOY would it need to be out
    of calibration for it to show 50Hz instead of 60Hz.
    MAYBE, more fool proof, but I doubt more precise.
    Plus, he can see any distortion in the sine wave.
    Do that with your clock.
    So, someone questions you and they are a fuckhead?

  14. Phil Allison

    Phil Allison Guest

    "James Beck"

    Another congenital moron fucking up a potentially useful NG.

    ........ Phil
  15. James Beck

    James Beck Guest

    All you gotta' do is leave.
    No need to beat yourself up.

  16. Phil Allison

    Phil Allison Guest

    "James Beck"

    Another congenital ASD fucked moron fucking up a potentially useful NG.

    ........ Phil
  17. James Beck

    James Beck Guest

    Please, stop top posting.
    People will think you are some mean spirited asshole and not the self
    flagellant that you really are. Now, be an adult and go away quietly.


  18. If he could do that, he wouldn't need the Talcum powder! ;-)

    Service to my country? Been there, Done that, and I've got my DD214 to
    prove it.
    Member of DAV #85.

    Michael A. Terrell
    Central Florida
  19. Phil Allison

    Phil Allison Guest

    "James Beck" <

    What a fucking hoot !!!

    The above, slimy, sub human pile of *white trash* from Georgia is a
    coin-op machine tech !!

    Now the * penny drops * how come this congenital wanker is such a know
    nothing scum bag.

    ROTFLMAO !!!!

    ......... Phil
  20. James Beck

    James Beck Guest

    Yep, been in the coin op business for almost 25 years.
    I make no attempt to hide what industry I work in or what my email or
    web address is. Why would I?
    You really need to have your meds increased.
    Such a spewing of hate and anger EVERY time someone questions something
    you say. Now, since you are so much higher and mightier than I am you
    will have no problem holding your tongue and going away like an adult,
    but no, you will have to respond once again to fulfill your compulsion
    to get in the last word.

Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day