strange pbroblem...

Discussion in 'General Electronics Chat' started by uttarkar.msrao, Jul 30, 2014.

  1. uttarkar.msrao

    Thread Starter New Member

    Jul 29, 2014
    4
    0
    Hello everyone,
    I am new to dis community and i hope i will get the solution.
    Please Someone go through this,
    "I have connected 24 v Dc lamp to Dc source ckt.when there is no lamp in the lamp holder,24v is measured across the holder but when i fixed 24 v lamp,voltage dropping to zero.lamp not fused wen i connect the same to another source it is working."
    I dont know how can this be possible.somebody please explain.
    thanking in advance.
     
  2. tshuck

    Well-Known Member

    Oct 18, 2012
    3,531
    675
    The source in question doesn't have the capability of delivering the current that the lamp requires, which results in the voltage dropping.

    What are the two sources you are connecting to?
     
  3. MikeML

    AAC Fanatic!

    Oct 2, 2009
    5,450
    1,066
    It sounds to me that the first source is a lab supply that has "fold-back current-limiting".
     
  4. MrChips

    Moderator

    Oct 2, 2009
    12,441
    3,361
    It depends on your "source". What is the internal series resistance of the source?
     
  5. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    5,798
    1,103
    A very high resistance connection to one terminal of the lamp-holder could give the result you found.
     
  6. uttarkar.msrao

    Thread Starter New Member

    Jul 29, 2014
    4
    0
    Hello Sir,
    Here source is one and 22 indication lamps are connected in parallel...other ind lamps are glowing,except 4 ind.lamps.Hre i do not understand one thing,if voltage dropping to 0 V,it means it is shorting,if it is shorted,why not either lamp or its fuse blown out.
    Thank you for replies...
     
  7. uttarkar.msrao

    Thread Starter New Member

    Jul 29, 2014
    4
    0
    i will try as u said Mr Alec t..
     
  8. MrChips

    Moderator

    Oct 2, 2009
    12,441
    3,361
    Hello Mr uttarkar.msrao, welcome to All About Circuits.

    Notice that everyone that responded to your thread took the time to write out their posts with proper spelling, grammar, punctuation and capitalization.

    This should tell you something. On AAC we take the effort to communicate properly in written text with proper English and no textese.
     
  9. uttarkar.msrao

    Thread Starter New Member

    Jul 29, 2014
    4
    0
    Ok Sir, I admitted the terms.
     
  10. alfacliff

    Well-Known Member

    Dec 13, 2013
    2,449
    428
    probably a high resistance in the supply to the lamps that are not lit. if it were shorted, it would have cut off current to all lamps. check the wireing and connections to the lamps that are dark.
     
Loading...