Death by Capacitor?

t06afre

Joined May 11, 2009
5,934
As have said many times in this forum. Then it comes to electrical shock. it will much depend on the path taken by the current. Some types of tissue like the heart is quite
vulnerable to electrical shock. Others not. Surgeons use electrical current to cut tissue, but not near the heart.
 

radiohead

Joined May 28, 2009
514
I advise people to discharge all capacitors prior to monkeying around in the chassis of any electrical device. And oh, by the way, make sure it's unplugged when you discharge those caps.
 

Adjuster

Joined Dec 26, 2010
2,148
A fairly basic form of defibrillator is based on a capacitor plus a series choke, switched between a charging supply and the patient by means of a relay (possibly a vacuum type). More recent developments provide more complex waveforms, but as far as I know capacitors still provide the basic energy store.

http://en.wikipedia.org/wiki/Defibrillation
http://www.frca.co.uk/article.aspx?articleid=100392
http://www.ebme.co.uk/arts/biphasic/defib3.htm

I think that however the exact detail of a modern defibrillator is probably a bit beside the point as far as the OP's original enquiry is concerned: the fact is that charged capacitors can deliver profound electric shocks.

Actually, Benjamin Franklin is said to have used charged capacitors (Leyden Jars) to electrocute birds way back in the 1750s, and apparently he got pretty badly zapped himself - I wonder who was the first non-survivor of such an episode?

http://www.masshist.org/objects/cabinet/december2002/december2002.htm
 

capnray

Joined Jul 3, 2010
59
A defibrillator is intended to shock the heart muscle out of an irregular rythm. It actually stops the heart and allows it to restart, hopefully in correct rythm (reboot!). The basic EMT can use it to correct V-fib or pulseless V-tachacardia. Paramedics administering drugs may use it for other arrythmias, including A-fib, however the person with this condition is usually conscious and you only get one shot, the patient gets a little wary.
 

nbw

Joined May 8, 2011
36
I have a 100V 76,000uF capacitor in the shed a friend gave me. He used to call it Eleanor after the brute car in 'Gone in 60 seconds' - warning that shorting the 2 terminals when charged was like a handheld welder.

Yep, I reckon it could kill, don't want to try though.

I also think jumping off a 4 storey building would kill me. Can't be sure - never done it - but I'm going to file that, and Eleanor, in the "extremely likely serioous damage would occur" category :)
 

shortbus

Joined Sep 30, 2009
10,049
Yep, I reckon it could kill, don't want to try though.

I also think jumping off a 4 storey building would kill me. Can't be sure - never done it - but I'm going to file that, and Eleanor, in the "extremely likely serioous damage would occur" category :)
@nbw- as the last thing on your "Bucket List" you could take Eleanor to the roof of a four story building and ......... :p:eek:
 

Jotto

Joined Apr 1, 2011
151
Had a friend die from touching a PFN of a radar that hadn't been properly discharged. Pulse forming network which is a bunch of capacitors.
 

Jotto

Joined Apr 1, 2011
151
It was off. You must discharge the PFN to ground anytime your working on the units transmitting section. If left sitting it can build up another charge and get you again, but usually not fatal.
 

DerStrom8

Joined Feb 20, 2011
2,390
It was off. You must discharge the PFN to ground anytime your working on the units transmitting section. If left sitting it can build up another charge and get you again, but usually not fatal.
And that, my friends, is why you should use bleeder resistors.... :D
 

maxpower097

Joined Feb 20, 2009
816
I've always been told to be careful with power supply caps, and old CRT caps. That may be a direction to narrow your search to find one. I'm sure its happened before its just a matter of searching it out from the millions of other deaths. Anytime you enter killed or died into google you get a flood of results no matter what else you put with it.
 

awright

Joined Jul 5, 2006
92
As one who has been defibrillated with multiple shots on three occasions, I feel like somewhat of an authority.

The strategy, as it was applied to my situation, was to stop the heart (that was arrythmic due to my being born with a fast, redundant nerve path between chambers that "short-circuited" the normal nerve with the necessary chemically-mediated time delay) with one shot, then restart it with a second shot - hopefully with normal rhythm. The fact that I am here to type this indicates that it worked, including the heart stopping phase.

I'll spare you the full story and obligatory viewing of my operation scars except to say that I can guarantee you that a capacitor discharge can stop the heart and, in the hands of an expert, can also start one. And, cjdelphi, defibrillation is exactly discharge of a capacitor through the body. The defibrillator jolt is rated in Joules of energy (or, identically, watt-seconds), just as a photoflash discharge is rated. I assume there is circuitry in the discharge path to control and shape the pulse, but it is a capacitor discharge.

The defibrillator that I happen to be familiar with has energy settings from 2 to 360 Joules, about the range from a small compact camera flash unit to a large professional flash unit. And I doubt that they use it at max energy until they've exhausted the possibility of getting the desired results at much lower than max setting.

So, my advice is, treat any possibly charged capacitor with respect and care.

awright
 
Top