22 Sep
2008
22 Sep
'08
10:07 a.m.
Current above 30mA at 50/60Hz is leathal..
48V / 50Hz is presumed to be save and 110V DC is the highest save DC
voltage.
This according to Dutch savety regulations NEN3140.
-Rik
-----Oorspronkelijk bericht-----
Van: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org]
Namens Brian L. Stuart
Verzonden: maandag 22 september 2008 16:55
Aan: General Discussion: On-Topic and Off-Topic Posts
Onderwerp: High voltages (was a new BBS...)
Ok, let's be serious here: Most of the shock
you take from CRTs is
more "oops" than electrical shock. A 26000 volts shock hurts, but not THAT
bad.
There isn't enough power to make your heart stop.
If the monitor is
turned on, the frequency is so high that the electrons travel on the
top of your skin. If the monitor is off, there is NO enough charge on
the tube, and it is discharged by a some megohms resitor to ground.
Period. So it is not a life concern, but only the scare.
Don't be scare of CRTs, they bite but don't hurt :o)
Electricity and the human body are a weird combination with often unexpected
results. Lo these many years ago back in high school, I took my Yaesu HF
rig to school to show the class a little about ham radio. After demoing
things, I powered it down and opened it up to show them what was inside.
Then I made the fateful move (well, not so fateful; I'm still here to tell
the story) to open the cage with the transmitter final tubes. Things had
been powered down for a while, about 20 minutes as I recall. I reached in
to see if the tube was still hot and got close to the plate connection on
the top. The tip of my finger was close to that and the side of my finger
just past the outermost knuckle was close to the grounded cage. The shock
threw me back against the wall behind me. When I looked, there were a
couple of nice little "holes" in my finger. The one on the side looked as
if something inside had blown outward. Of course, after the "what the....?"
my first thought was, "guess the caps in the plate circuit hadn't discharged
yet."
PS: I'm not a medical doctor, I don't
warrant you of nothing I
said here. If you put your tongue on the wrong flyback end and it
hurts, I'm not responsible. Void where prohibited. Your milegage may
vary. Batteries not incluided. If you die because anything I wrote
here, the problem is enteirely yours.
Ditto...
BLS