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RE: Inexperience was RE: Mad experiment or Re: PDT



Original poster: "Dave Hartwick by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ddhartwick-at-earthlink-dot-net>

Original poster: "Crow Leader by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<tesla-at-lists.symmetric-dot-net>

All these "horror" stories are wonderful and such, but don't actually
educate anybody as to say prevent accidents with a tesla coil. I cannot
imagine most tesla coils are powered off 3 phase 480 volts factory buss bar
with nearly unlimited power levels. Your average tesla coil will not weld
you into a breaker box, or make you fall off a utility pole while setting
you on fire.
>>>>>>>>
Wow, you are mistaken Ken. Once you start powering with PDTs or MOT supplies
connected to 240 VAC service, you are dealing with potentially devastating
energy levels at all system locations:
Supply LV, and HV, and coil discharge. I would afford as much respect to
single phase 240 service as 3 phase 480 VAC service.

You did mention average tesla coils, of course. If this is a coil powered by
1 or 2 15/30 NSTs, then you're right; but anything above this, especially if
powered by minimally current limited transformers, should command infinite
respect. All coils should command respect, at least as a matter of course.
This is not to say that one should become overly fearful. Solid, measured
safety levels should be observed. I do not think scads of interlocks are
necessary, for example.

I'm thinking that a coil powered by a 5 kVA PDT is about an average coil--a
highly subjective standard, obviously. Maybe 1.5-2 KW NST powered coil is
more realistic.

As always, I yield to the masters on this stuff, and address my comments to
your thoughts with all due respect.
Dave H
>>>>>>>>


As for Viktor's questions, keep in mind that the output of a small coil
might not do much aside from burn you. The primary coil and caps can kill
you easily. If you do feel the need to play with the output of the secondary
directly, you will want to avoid any means of falling into anything dealing
with the primary. You will want to make sure that your secondary arcs are
not picking any current from the primary as well. As you can tell from
reading posts, people get strikes to their primary all the time. It
inherently seems like a bad idea to intentionally play with your secondary
arcs knowing this. Tesla coils behave in strange ways and you will probably
want too observe the strange things that happen (as in sparks glong long
distances and not to the nearest grounded object) before trying your
"experiment".

KEN


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, September 23, 2002 11:28 PM
Subject: Re: Inexperience was RE: Mad experiment or Re: PDT


> Original poster: "Daniel Barrett by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <dbarrett1-at-austin.rr-dot-com>
>
> >
> > Another example of the cavalier attitude about the danger of high
> > potentials is prevalent is my current profession. I work in Commercial
> > Kitchen Equip. Repair. I commonly work with voltages of 240 and 480 with
> > supplies of up to 200A or greater! There isn't one time that I open a
> > panel of 480/150A that I don't pause for the cause, but I watch techs
> > poke and prod around live circuits like it's all made of 120/10A! I
> > watched one trainee check a circuit with a Fluke voltage probe (the
> > little ones that glow if voltage is present) find no indication and then
> > promptly grab the lines and shock the smile right off his face!! He did
> > not know that if you test with the Tester, putting it in certain places
> > (i.e. directly between two lines) you'll get false readings. His
> > inexperience cost him a couple of burns and a bruised ego. He was lucky!
> >
>
>
>     One this note, a story related to me by a coworker-
> A trained/cluefull/careful technician was working on a piece of HV gear
and
> got zapped. That was not much of a problem in and of itself. His life got
> complicated because the jolt threw him into an open 440VAC panel, and a
> wrench in his tool bag found two of the three legs in the panel. The
> resulting explosion blew his left buttock OFF.
>     The point is that the collateral damage that may occur when you get
> zapped can be worse than the zap itself- if a little streamer hit from
your
> coil cause you to spaz out and dump your beer onto your primary...
>
> db
>
>
>
>
>