what is this

Discussion in 'General Electronics Chat' started by Globeworker, Aug 6, 2015.

  1. Globeworker

    Thread Starter New Member

    Aug 6, 2015
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    Hi, wonder if anyone can help me. I have this energiser board that I have replaced the resistors on but I'm stuck as to what the item is on the photo. Is it a capacitor? There are no markings on it. The board has LP1 marked in its place.

    It looks like a blown glass bulb but don't think it is a bulb as it is inside a sealed box.

    image.jpg image.jpg

    Any help would be great,
    Cheers
    Chris
     
  2. pwdixon

    Member

    Oct 11, 2012
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    LP usually means lamp, just because it's inside a case doesn't mean there can't be a lamp in there.
    Could be a neon perhaps.
     
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  3. KJ6EAD

    Senior Member

    Apr 30, 2011
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    It looks like an NE2 neon lamp and the 47k resistor feeding it would be right for 120VAC but sometimes they're used as a high voltage trigger instead of for their light output.

    http://www.bristolwatch.com/ele/neon.htm
     
    Last edited: Aug 6, 2015
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  4. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    This is definitely a neon lamp. Generally they are used to indicate the presence of high voltage.
     
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  5. Globeworker

    Thread Starter New Member

    Aug 6, 2015
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    This board is to energise an electric fence 12volt dc system
     
  6. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    Yes, that outputs 10kV.
     
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  7. KJ6EAD

    Senior Member

    Apr 30, 2011
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    Okay. High voltage trigger function then.
     
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  8. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    Agreed.
     
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  9. blocco a spirale

    AAC Fanatic!

    Jun 18, 2008
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    Or, it's only there to indicate the presence of HT.
     
  10. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    *ahem*

    :p
     
  11. MaxHeadRoom

    Expert

    Jul 18, 2013
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    +1 for trigger neon, usually when they go black like that their useful life is over.
    Max.
     
  12. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    I put a HV bird wire zapper on a lighthouse. The power unit has a neon lamp on the front to indicate it is working.

    This unit puts out a pulse about once a sec, and ytou can confirm it is working by observing the neon bulb.

    I also got a tester for the lines, basically a series of neon bulbs marked for voltages in the 1,000's of volts. Each lamp meaks a higher voltage.

    Not very arrurate but no one really cares if it is 2,387 volts when "over 2KV" is ample information.
     
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