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harry harry is offline
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Default Tossing a charged Capacitor in the Bathtub

On Jan 27, 11:48*pm, wrote:
On Fri, 27 Jan 2012 09:56:12 -0800 (PST), DerbyDad03





wrote:
On Jan 27, 11:53*am, wrote:
Most people know that dropping a cord or appliance that is plugged into
an outlet into a bathtub filled with water will electrocute the person
in the tub. *Yet, you can drop a low voltage item such as a flashlight
with batteries in the tub and no one will be hurt. *Even a set up jumper
cables connected to a car battery would not likely do anything, or might
just tingle a little (never tried this, but I've handled plenty battery
cables while standing on wet soil in wet shoes and never felt a thing)..


Not that I'm planning to test this, but what would happen if a large
capacitor, charged with 200 volts or more was tossed into a filled
bathtub while someone was in the tub? *(By large capacitor, I dont mean
the size, but rather, I mean a large capacity, such as 500 MF or one
Farad or more....).


I see no reason this would ever occur, but I'm just curious.


[NOTE: This could be DC or AC]. DC capacitors are used in electronics,
while the AC type are motor start capacitors.


I don't know what will happen when you toss it in the water, but I
know what will happen when a dead man stick is used to short the
terminals of a large cap charged up to 7 or 8 KV DC.


A dead man stick is a device with a wooden handle with a hooked rod
threaded into the handle and a braided strap with a clip on the end.
It was used to both ground towers and other electrical equipment or to
pull an energized human from said equipment.


At a minimum, shoting out the cap will cause a bang and a spark that
is sure to strike fear into the hearts of most mortal men. In some
cases, it will blow 4 inches of threaded rod out of the hardwood
handle.


We used to do it quite often when I was in the Coast Guard as training/
warning exercise.


We had large oil filled caps (5F) that ran at 15 - 20 KV DC in the
LORAN transmitter buildings. We didn't want non-Transmitter Techs in
the building without one of us present. As new men would arrive at the
station, part of the orientation meeting included a demo where we
would use a Hi-Pot to charge up a cap to at least 5KV DC, turn out the
lights and then short it out with a dead man stick. One time we went a
bit overboard with the Hi-Pot and I was left holding a smoking hard
wood handle while my buddy retrieved the metal rod from across the
room. We grabbed another dead man stick and still got quite a bang out
the cap since it didn't completely discharge before blowing up the
other dead man stick.


That one even scared me!


Damn, I never knew they even made caps that big. *What was the actual
size of that thing? (roughly). *Or is there a photo on the web?

That sounds like quite a charge to see (literally) lol..- Hide quoted text -

- Show quoted text -


They make capacitors big enough to run electric vehicles off these
days.
http://en.wikipedia.org/wiki/Super_capacitor