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#22990 - 03/09/03 09:24 PM electric chair voltage
Edward Offline
Member

Registered: 12/14/02
Posts: 309
Loc: California
If it is the current that kills, then why does the electric chair use high voltage to execute?
If they use 480 Volt the person in the chair will probably die with in seconds right??

then why use higher voltage?

Edward
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#22991 - 03/09/03 09:59 PM Re: electric chair voltage
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Edward,
An Electrical Electrocution Device, must by International Law, use no more than 120V, the current is only limited by the resistance of the "load".
Anything you heard ahout High Voltage, is Media Hype!.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

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#22992 - 03/10/03 05:16 AM Re: electric chair voltage
frank Offline
Member

Registered: 05/29/01
Posts: 361
Loc: windsor ontario canada
Heres a link old sparky's FAQ.See question #16. http://www.albany.edu/~brandon/ecfaq.html

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#22993 - 03/10/03 06:04 AM Re: electric chair voltage
txsparky Offline
Member

Registered: 05/25/01
Posts: 578
Loc: Magnolia,.Texas U.S.A.
from link...
 Quote:
The voltage has tended to increase over time and in the modern era the voltage is usually 2,000 to 2,200 volts at seven to twelve amps.
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#22994 - 03/10/03 09:22 AM Re: electric chair voltage
C-H Offline

Member

Registered: 09/17/02
Posts: 1508
Loc: Stockholm, Sweden
Trumpy,
120V would be more like what you use for torturing people, when you don't want to kill them.

The electrical chair is one inefficient way of killing people. When you have hand guns which nearly always work, why invent something that is both complex and inefficent?

Edward,
the voltage used has to do with probability: A current of 10mA can kill, but will not in 99% of cases. Still, when it comes to safety you want to save that last percent of people too. Therefore the trip current of GFCI's is very low.

Something like 500mA will kill 99% of people, but you want 100% of people to die in an electric chair. Therefore, a higher voltage and with it a higher current is used.

Also, you die in different ways depending on the the current: If it's really high you burn. If it's not that high, you're hearth will stop instantly. Lowering it further means that the hearth will not work correctly, which will kill you a bit slower. A really low current will "just" paralyse your muscles, which means that your breathing will be affected. This can kill you too, but it will take some time.


[This message has been edited by C-H (edited 03-10-2003).]

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#22995 - 03/10/03 01:56 PM Re: electric chair voltage
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Somewhere in the 1500-2400V range seems to be the norm, but apparently the systems used (or formerly used) in some states would automatically cut the voltage back after a few seconds.

I've found documents which state that the Georgia chair, for example, was specified as 2000V for 4 seconds, followed by 1000V for 2 seconds, followed by 208V for the remainder of the 2 minute cycle.

I've seen another spec (VA I think) which applied something like 1800V for 15 or 20 seconds, followed by 600V for another 40-45 seconds.

The explanation is that the initial higher voltage is to knock out the brain and render the prisoner unconscious as quickly as possible, then the reduced voltage is to minimize burning. The 1 to 2 minute cycle is supposedly necessary to ensure complete cardiac and respiratory failure.

All texts that I've read suggest that most of the resistance of the human body is in the outer layers of skin. Once they are broken, the resistance of the body tissues inside is quite low. Another point I've seen put forward for the high voltage is that it breaks down the skin's insulation and allows a greater current to flow.

I recalled a discussion we had about this some months ago, and I found the link from back then. The table below gives voltage and current readings from Florida's chair, which in its modern form apparently had a more sophisticated control system which regulated the current by reducing the voltage as necessary during each of 3 cycles.

 Quote:

The last five executions provided the following:

Inmate Cycle Volts Amps Ohms
Buenoano
1 2000 9.4 212.8
2 650 2.9 224.1
3 1900 9.4 202.1

Remeta
1 2100 9.2 228.3
2 675 2.9 232.8
3 1850 8.9 207.9

Stano
1 1600 9.1 175.8
2 550 2.9 189.7
3 1500 9.0 166.7

Jones
1 1600 9.1 175.8
2 500 2.9 172.4
3 1450 9.2 157.6

Davis
1 1500 10 150
2 600 4.5 133
3 1500 10 150


Just see how low the resistance of the body (head-to-ankle) can get.

{Edit: The auto formatting in the forum software has distorted the tables a little. They're from this link .}

By the way, the case of Willie Francis referred to in the FAQ linked above is fairly well documented. Although he did indeed survive the first attempt at his execution, he did so only because the officials in charge made a mistake. Apparently Louisiana at that time (1940s) used a portable chair which was taken to the parish in question for each execution. A guard made the wrong connections which resulted in only 200V or so being applied when the switch was thrown (I'm guessing 208V from a normal 120/208 system?).


[This message has been edited by pauluk (edited 03-10-2003).]

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#22996 - 03/10/03 08:21 PM Re: electric chair voltage
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
paul — Killer Link! [pun intended]

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#22997 - 03/10/03 08:37 PM Re: electric chair voltage
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
My God!,
I bet the people on Death Row are glad, I don't run the executions, eh!.
Can't remember where I read that, but I won't reading that tripe again.
Can I take my foot out of my mouth,now?.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

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#22998 - 03/11/03 12:28 AM Re: electric chair voltage
C-H Offline

Member

Registered: 09/17/02
Posts: 1508
Loc: Stockholm, Sweden
 Quote:
I bet the people on Death Row are glad, I don't run the executions, eh!.

You'd probably have to leave them on all night...

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#22999 - 03/11/03 02:50 AM Re: electric chair voltage
gramps Offline
Member

Registered: 08/25/02
Posts: 120
Loc: ohio
ah, for the days of Judge Roy Bean (the hangin' judge)!! all you needed then was a rope, and a good, stout tree.


gramps

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