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How is it done?

Bill.Chancellor

Sep 29, 2009
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Sep 29, 2009
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Hi,

I'm an old mechanical engineer. I'm struggling to understand how a taser is able to step up the voltage from a 9 volt battery to about 300KV. Background....I understand the coil concept in the older automobile ignition systems and how it moves the voltage from 12 volts to 20,000 volts for the spark plugs but, how did the electronics world replace that large coil with something so small it can fit in the palm of your hand?

Thanks in advance....Bill Chancellor 9/29/09
 

Resqueline

Jul 31, 2009
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Jul 31, 2009
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I haven't seen inside a modern taser but I'll give some general clues.
Increasing the frequency is one way to reduce the size and weight of transformers, coils, & capacitors.
Aircraft instruments, fans, and transformers have long since been operated at 400Hz instead of 50-60Hz because of this advantage. Your 300W PC PSU operates at least at 30kHz and weighs next to nothing compared to an iron transformer of the same rating. Your cell phone charger operates around 100kHz maybe, weighs nothing and puts out several watts.
Time is another factor for high voltage breakdown. Capacitors can withstand over twice their rated voltace for a couple of seconds or minutes, but give them 20 minutes and they're surely busted. Same with transformer breakdown.
The rating of the output is also something to have in mind, it's probably along the the lines of the audio industry with its PMPO exaggerated numbers. 300kV is most likely a peak-to-peak number, which is meaningless in terms of breakthrough power. The peaks of 150kV is what matters, and the mean/average voltage is probably less than a fifth of this.
 
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