High voltage safety precautions

[bz]

"JB" <nospam@goofball.net> wrote in news:C31Nl.69$5F2.54
@nwrddc01.gnilink.net:

"PeterD" <peter2@hipson.net> wrote in message
news:aaa805lqp2tcbkcoa4g29l3hfqmo4g6svu@4ax.com...
On Fri, 8 May 2009 06:04:06 -0500, "Mark Zacharias"
mark_zacharias@labolgcbs.net> wrote:



More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap.
Gotta
be more careful..."


Mark Z.

Funny thing is that 120 volts AC is actually more likely to kill you
than 240 volts!

Only because you may be exposed to it a lot more often.

No! Because 240 is more likely to 'throw you off' and 120 is more likely to
'freeze you on'.

15 micro amps across the heart kills. 60 Hz is especially bad for causing
V-fib. Without a defibrillator, or CPR you are dead in 6 minutes.

15 milli amps is sufficient to 'freeze your muscles' so you can't let go.
You start with relatively dry skin and get a good grip onto a hot item.
You can't let go.
Skin at the points of contact blisters.
resistance goes down.
current goes up.
you cook.

Higher voltages produce very violent muscle contractions and can (if you
are lucky) throw you clear of the circuit.

Consider that at
240v you will be dissipating 4 times the power through your bod!

--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+ser@ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap

 

On May 6, 7:36 am, 1PW <barcrnahgjuvf...@nby.pbz> wrote:

On 05/04/2009 04:52 AM, ragno.stef...@gmail.com sent:

Hi,

I'm going to do some experimentation on high voltage equipments
( transformers, power supplies, capacitor banks, lasers , etc.. ).

Does anyone know where I could find some safety guidelines or notes
about working with this dangerous stuff ?

( I wouldn't like to die because of a spark jump and make my wife a
widow... )

Thanks

Stef

Hello Stef:

Please define the levels of high voltage you are referring to.

Laser safety is also an entirely different subject. What type & class
laser?

Pete
--
1PW @?6A62?FEH9E=6o2@=]4@> [r4o7t]

I refer to voltages found for example in CO2 lasers and CRT chassis.

I found a nice page with guidlines: http://www.repairfaq.org/sam/safety.htm

Is there a rule for how long a spark can jump, given the voltage and
the dielectric ( tipically air at certain humidity) ?

Furthermore, why should I keep a hand in my poket while around HV ?