Help with xenon flash circuit

Discussion in 'The Projects Forum' started by Небојша Илић, May 20, 2017.

  1. Небојша Илић

    Thread Starter New Member

    May 14, 2017
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    I need help with this circuit. F.T. Capacitor Cs is 330V 800uf, Ct is 400V 0.047uF, resistor is 5.1M, triger coil is TC-36.
    In this circuit capacitor Cs discharge through flash tube with full power.
    I want to control discharging power in steps of 1/2, 1/4, 1/8 ...
    How could this be achieved? xenon-flashtube-principle.gif
     
  2. bertus

    Administrator

    Apr 5, 2008
    18,613
    3,607
    Hello,

    The ciruit only works when the capacitor is charged with a high voltage.
    There are circuits that will charge the capacitor from a battery.
    See the attached PDF for more info.

    Bertus
     
  3. Небојша Илић

    Thread Starter New Member

    May 14, 2017
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    O
    O.K. Thanks for image, but I know how capacitor is charged, and how flash tube works. I dont know how to reduce/limit capacitor discharge into lamp to produce lower power of flash (1/2,1/4, 1/8...).
     
  4. Reloadron

    Distinguished Member

    Jan 15, 2015
    3,645
    1,646
    Which brings us to:
    The above quote was taken from here.
    So it becomes a matter of controlling the actual flash duration.I could have a bank of for example four capacitors and choose one of four to control my flash duration. Just as an example Full Power = 8,000 uF, 75% Power = 4,000 uF, 50% Power = 2,000 uF and 25% or 1/4 Power = 1,000 uF. I can mechanically switch or I can electronically select .
    Variable Strobe.png
    I can electronically or manually choose the capacitor I want and control the actual flash on time.

    Ron
     
  5. Sensacell

    Moderator

    Jun 19, 2012
    1,989
    618
    Commercial flashes control the power level by placing a switch (usually an IGBT) in series with the flash tube.

    The flash power is controlled by timing the switch, cutting it off mid discharge for 50%, for example.
     
  6. Небојша Илић

    Thread Starter New Member

    May 14, 2017
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    I was assuming something like that.
    Any idea for circuit wherе to put IGBT or even thyristor?
     
  7. Небојша Илић

    Thread Starter New Member

    May 14, 2017
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  8. Небојша Илић

    Thread Starter New Member

    May 14, 2017
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    OK, that is one idea I have been considering, but I am more interested in circuit with only one big capacitor. I found on net information that is done by thyristor and series of resistor, but so far I couldnt find a funcional circuit.
     
  9. Reloadron

    Distinguished Member

    Jan 15, 2015
    3,645
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    Using Google I can find block type diagrams but I am also having a problem finding an actual circuit. Anyone have anything?

    Ron
     
  10. Небојша Илић

    Thread Starter New Member

    May 14, 2017
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    Post some of its here. More useful informations, more chances to find solution for this.
     
  11. Небојша Илић

    Thread Starter New Member

    May 14, 2017
    7
    0
    I found this circuit on some russian site. It is circuit board marked EPT260-01B.
    But, where are wires 1, 2 and 3 connected?
    And here is the link http://impulsite.narod.ru/hanimex/tz2/03ede5bc3296.png
     
    Last edited: May 24, 2017
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