Re: drsstc (Capacitor Lethal charge)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Sparktron01-at-comcast-dot-net 

David, Bob

The standard safety "rule of thumb" is any capacitor over 10J stored
energy is considered lethal.  Voltage definitely enters into mix (a 30V cap
is certainly less dangerous shock wise then a 3kV one), both can cause
thermal injuries.  I don't know where that 10J figure comes from
however here is quick independent source that supports that...

<http://www.stephstuff-dot-com/esafe/StoredEnergy.htm>http://www.stephstuff-dot-com/esafe/StoredEnergy.htm

As a side note, it is a requirement of the National Electric Code
2003 that any capacitor then 0.1uF or larger charged with 250VDC
or more shall have bleeder resistors installed.

Regards
Dave Sharpe, TCBOR/HEAS
Chesterfield, Va. USA

-------------- Original message --------------

 > Original poster: DRIEBEN-at-midsouth.rr-dot-com
 >
 > Hi Bob,
 >
 > The defibs that I've seen in my profession (firefighter)
 > generally have two energy level shock settings - 200 joules
 > and 360 joules, so I would assume that they are not charged
 > up to their maximum rated voltage for "shocking". Seems
 > strange that an electric charge that would almost certainly
 > be lethal to a normally healthy, conscious person can "shock"
 > a fibrillating heart back into the "normal" electrical ry-
 > thym, thus possibly saving a life. Dosen't it only take a
 > couple of joules to be mortally dangerous?
 >
 > David Rieben
 >
 > ----- Original Message -----
 > From: Tesla list
 > Date: Saturday, October 23, 2004 6:38 pm
 > Subject: Re: drsstc
 >
 > > Original poster: "Bob (R.A.) Jones"
 > >
 > >
 > > Subject: Re: drsstc
 > >
 > >
 > > > Original poster: "David Rieben"
 > > >
 > > > Bob(s):^),
 > > >
 > > > The latest capacitor technology has caps of much smaller
 > > > volume/energy ratios than either of the caps that you mention.
 > > > Difribrillators have a capacitor of appr. 5.2 kV at around
 > > > 35 to 40 uFD rating and they are not much larger than say two
 > > > combined microwave oven filter caps. I suppose their
 > > > peak current rating dosen't have to be that great since
 > > > they're designed to discharge across a relatively high
 > > > resistance - human chest :^O Even with the conductive gel
 > > > that they apply to the skin before shocking, the resistance
&!
gt; > > would still probably be in the dozens, if not hundreds of
 > > > Ohms.
 > > >
 > >
 > > Hi David,
 > >
 > > Thats very very impressive 540J in the volume of 2 MO caps WOW. That's
 > > comparable to an electrolytic cap for energy density.
 > > It would require more than 1500 Panasonic 0.15uF/2kV to do that.
 > > But as its has been said before its one thing for a cap to have to
 > > chargefor a few seconds a few times a day.
 > > and its a completely different duty to operate continuously.
 > >
 > > Seriously off topic (sorry Terry) but what the h$## are they
 > > trying to do to
 > > the patient 540J into his chest!!
 > > Does it double as an elephant defibrillator too !!
 > >
 > > Bob
 > >
 > >
 > >
 >
 >