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Neon sign, transformer failure

  1. Jan 3, 2010 #1
    Hi all-
    Can anyone offer any insight into a problem I've noticed for years but don't know how to solve?
    I'm a self taught neon tube bender. I am not an electrician or electrical engineer.
    Through the years, I've noticed neon tube, fluorescent lamp, transformer and ballast failure more often at restaurants than other places, in downtown areas in cities as opposed to smaller suburban locations and where the city provides the power.
    Guys on a sign repair truck do basic voltage tests but not much more. They aren't really trained (around here anyway) in anything more technical.
    When I bring up the subject, most companies I deal with are more concerned with getting the job done and getting paid.
    What can I look for besides voltage spikes, sags etc.? Who would have the proper testing equipment.
  2. jcsd
  3. Jan 3, 2010 #2


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    Before trying to hazard guesses for reasons for your your observations you should first consider the following.
    Are you sure that your observations are 'real'. Is the actual percentage of failures more or is it just that there are more fluo tubes in commercial premises? Also, how many hours are the tubes run or turned on/off in the different conditions? On/off can stress tubes. Are they all the same power rating or are the commercial tubes higher powered?
    This is a bit like a medical research project in which you have to normalise all the factors before you can decide on whether or not you have an actual cause and effect.
  4. Jan 3, 2010 #3
    Well, one problem restaurant is a national chain, signs manufactured by the same company,
    lamps and ballasts are the same and operating hours are consistent.
  5. Jan 3, 2010 #4


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    OK. Just needed to check.
    I don't have any ideas, though. Is this a UK or US situation?
  6. Jan 3, 2010 #5
    Are these outdoor or indoor signs?

    If outdoor, perhaps contamination from chimney or cooker hood exhaust fumes has some effect.

    If indoor, are the transformers in or near hot, humid kitchens?
  7. Jan 3, 2010 #6


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    Perhaps the national chain gets the lowest bidder for the signs. Just saying.
  8. Jan 4, 2010 #7
    Outdoor, not near any type of kitchen exhaust
    Lowest bidder, yeah probably, but the same name brand lamps and ballasts are used throughout the industry.
    Does anyone know anything about: 1. Harmonic distortion
    2. transients
  9. Jan 4, 2010 #8


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    One place that I played guitar at had VERY noisy AC power. I worked with the bar-maid to figure out what was the source, and found that the lights over the back-bar were on a dimmer that was causing the noise. The only way to stop the buzzing in the amps and PA was to either turn those lights all the way up or shut them off. Commercial establishments like restaurants often have entire banks of lights on dimmers. Perhaps this could be a contributing factor in shortening transformer-life.
  10. Jan 4, 2010 #9
    These are the large outdoor road signs. I have used that same buzz in an AM radio
    to determine which neon tube bordering the interior of a restaurant was starting to go bad, even though all of the tubes looked good.
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