Jacobs Ladder / Battery Power

Discussion in 'The Projects Forum' started by NZMikeV, Jul 5, 2010.

  1. NZMikeV

    Thread Starter New Member

    Jun 18, 2010
    Hi there
    I have a couple of question regarding a (non-mains) high voltage project that I am investigating.

    There is a kit available for making a small Jacobs Ladder display which runs off a 12V car batterry and requires a seperate 12V ignition coil. I haven't bought it yet so no schematic to show you but the product description refers to Silicon Chip Magazine April 2007 for anyone interested.

    1) Is it possible to construct a Jacobs Ladder that runs off a 6V SLA or is that asking too much of the battery?

    2) How dangerous is the high-voltage output when running off a 6V or 12V SLA battery? (Assuming a low current given the high voltage). Would accidentally contacting the "sharp" end put you underground, in hospital, or just scare you witless? (I grew up on a farm with 4kV electric fences so gained a healthy respect of high voltages at a young age. Ouch! :eek:)

    3) Whilst I'm asking about battery power: I HAVE NO INTENTION OF EVER constructing a taser or 'shocking' device, but is it true that a taser is powered by no more than 2 AA batteries ?

    Thanks in advance for any info.

    BTW: I might mention that I have seen quite a few Jacobs Ladder projects on the internet that are MAINS powered, and give very little, if any advice on safety other than "Don't touch the terminals!". For goodness sake!
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    If you look hard in the horror movies, you will notice that the electrodes are in glass cylinders, as the arc will blow out in any air current. They are pretty tolerable when battery operated, as they won't find you make a path to ground.

    As far as the 6 volt power goes, it might be possible with some mods. The ignition coil would almost have to be one for 6 volt operation, and the circuit might need some modifications.
  3. retched

    AAC Fanatic!

    Dec 5, 2009
    For Question 2,
    The 6v is going to be stepped up to a much larger voltage. That will give you a shock.. If the current is limited, it will still be dangerous, but only lethal if it goes across the heart, brainstem, or spine.

    For Question 3,

    Just like your cars coil, a taser steps the voltage up..to around 10,000V. But thats not all. The high voltage is oscillated at a frequency that is not supposed to affect life functions. It is only supposed to affect localized muscle.

    Now you can step 3v or 2 AA batteries up to 10,000v at .0001 amps. but not for very long.

    Your cars spark plug system is the same thing but without the frequency selectivity.

    You need voltage to ionize the air so that a path to the ground terminal (-) can be reached. It basically makes a wire out of ionized air particles. If you look at a spark plug, the gap you see is the same premise. The stub or electrode is at the end of the plug, then you have the "ground" after the gap. It that little "L" shaped piece that you bend toward or away from the electrode when setting the gap.