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Re: Safety FAQ is here -- draft, asking for comments.



Regarding this post...

> Was the oddest thing. As I was reading the note- TV Olympics anouncer 
> started talking about guy on crew team almost electrocuted with 30kV.
> 
> Anyway, my understanding about electrocution potential of AC vs. 
> frequency is that just as the human ear cannot hear much beyond 18khz, 
> neither can the body respond in much of any other way than sensing 
> heat dissipated at those frequencies.  Reason for both insensitivities 
> is supposed to be inherent slowness of nerves beyond these freqencies.
> 
> I've demonstrated this pretty well with flyback transformer and short 
> pulse at a variable rep rate.  When I've adjusted pot beyond where my 
> ear could hear mechanical vibration frequency, have only gotten skin 
> burns.  Below that shock seems to get worse, although I'm not sure if 
> its inversely linear with frequency.  

What you are describing is a classic example of the SKIN effect at 
work :)  NOT to be confused with voltage. 10:1 the 30kV was at 60Hz.
As frequency rises, current penetration becomes less (inversely 
proportional to square root of the frequency). I don't think nervous 
responses play any part in this.

Malcolm