Re: Of Mice and HV (fwd)

["High Voltage list" <hvlist@xxxxxxxxxx>]

Original poster: Steven Roys <sroys@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Sat, 15 Apr 2006 13:23:37 -0400
From: Luc Benard <ludev@xxxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Of Mice and HV (fwd)

HI Matthew,

As dangerous electricity is, killing in a reliable way with it is 
really hard; read about electric chair execution, they used a lot of 
power with good contact ( they used salt saturated water pad ) some 
time they need to applied the tension many time to finally kill. I also 
know a man who was strike by a power ( 14.4KV ) line, he loose an arm, 
a leg and have internal organ damage but he survived...

Cheers,

Luc


On 13-Apr-06, at 1:07 PM, High Voltage list wrote:

> Original poster: Steven Roys <sroys@xxxxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Tue, 11 Apr 2006 07:20:03 +0930
> From: Matthew Smith <matt@xxxxxxxxxx>
> To: High Voltage list <hvlist@xxxxxxxxxx>
> Subject: Of Mice and HV
>
> Greetings All
>
> CONTENT WARNING: If you are distressed by nasty things happening to
> vermin (small furry creatures to those not infested with them), please
> do not read any further.
>
> They don't make 'em like they used to!  Our house, completed just over
> two years ago (actually not completed, but that's another story!)
> appears to have been built to accommodate rodents just as comfortably 
> as
> humans.
>
> Snap traps have proved anything but reliable (bait gone, trap still 
> set)
> and when they do operate, frequently kill in an unclean manner.
>
> So, I have decided to build an electric mousetrap.  Idea is simple:
> mouse enters trap and has to pass through a narrow gap between two
> aluminium plates arranged in a V.  (Mouse enters the larger part of the
> V.)  One plate is fixed, the other against light spring tension so that
> the subject has to push between the two plates to get to the bait.
>
> Plates are connected to a charged capacitor.  Charging will be from a
> PWM supply driven by a microcontroller which stops when capacitor
> voltage reaches an upper threshold and starts again once it has
> discharged (mostly through the feedback voltage divider) down to a
> minimum voltage.  The idea being that this device is battery-operated
> and tries to save power.
>
> Does anyone have any idea what minimum voltage I would need to apply to
> guarantee fatal fibrillation?
>
> I had considered powering from a disposable camera supply (no
> microcontroller - simply pulse the start button when the neon goes out)
> but, whilst photoflash capacitors can give us a ghastly bite, is the
> 300V or so enough to take out a mouse in its insulating fur coat?  I've
> serviced equipment before where mice have gone in a mains (240V) PSU 
> and
> have blown the fuses but am still unsure about the certainty of a clean
> kill.
>
> Once I've got this idea working, I want to motorise it so that the
> defunct rodent can be cleared from the plates and the trap be readied
> for another "client".
>
> Cheers
>
> M
>
> -- 
> Matthew Smith
> IT Consultancy & Web Application Development
> http://www.kbc.net.au
>
>
>