Re Mot DC Ps

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Charles Hobson by way of Terry Fritz <twftesla-at-uswest-dot-net>" <charles.a.hobson-at-btinternet-dot-com>

Hi Luc

You sent:
----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, February 19, 2001 2:49 AM
Subject: Re: Mot DC Ps


> Original poster: "Luc by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<ludev-at-videotron.ca>
>
> Hi Chuck
>
> Tesla list wrote:
>
> > Original poster: "Charles Hobson by way of Terry Fritz
> <twftesla-at-uswest-dot-net>" <charles.a.hobson-at-btinternet-dot-com>
> >
> > Hi Luc,
> >
> > I looked at your web page gif:
http://pages.infinit-dot-net/luc2/mot_dc_ps.gif
> > It was a pleasure to see such a well drawn schematic. Several comments
on
> > the circuit though:
> >
> > 1. I can not see the need for the two lower sets of diodes connected
across
> > the 2.2uF capacitors. They don't appear to be doing anything.
>
> The P.I.V. on the diode is equal at the peak V of the transfo, with out it
> it's equal to 2X the peak V of the
> transfo and you have a little gain on the current ( around 5% )

I didn't think about that. A new one for my note book.
>
> >
> >
> > 2. I bread boarded your bridge circuit and applied a low A.C. to it to
test
> > it. Yes, it doubles the voltage. I then removed the diodes I mentioned.
> > Voltage doubling still occurred.
> >
> > 3. I don't think the circuit can be regarded as a full wave rectifier.
>
> English is not my natural language when I said full wave I mean double
> alternation .
Maybe not, but we speak the same technical language. "Double alternation" A
good way of putting it. Another one for my notebook.
>
> > The
> > 2.2uF on the right charges to the peak value of the two MOT's in series
> > (around 6kV) via the two top right diodes during 1/2 the ac cycle. Then
the
> > left 2.2uF capacitor charges to the peak ac value through the top left
> > diodes to  6kV during the other half of the ac cycle..The 2.2uF caps
with
> > their 6kV in series deliver the  12kV to the load.
> >
> > 4. This is still a pretty hefty 12kV dc power supply. I would be
concerned
> > about the 500k ohm power control. If you are after dc voltage control, I
> > think a conventional variac controlling the voltage to the MOT primaries
> > would be a better option:
> > .i e. safer to operate, efficient, etc.
>
> I choose this way because I plan to use this power supply with a RSG 20 to
> 800 bang /sec. the cap on the PS will
> always be charge at the maximum available ( less 60 Hz ripple ) and the
> resistance will help to decouple the PS
> cap from the tesla circuit.  Any way I have both: resistance and variarc.
> Operation will tell me what is the best
> set-up.

Good design approach. I am curious about the 2.2uF capacitors. That's all I
need to build a similar Power Supply.
>
> >
> >
> > 5. I may be stepping into a mine field here by saying the 120 Bangs is
not
> > applicable with a DC power supply. I think DC charging,  resonant
through an
> > inductor, or RC through a resistor, of your Tesla Coil primary capacitor
is
> > more appropriate. Bangs per second would be limited or determined by the
RC
> > time constant or the LC resonance.
>
> This is why I build this PS,  I want to use it at different rate of bang

I have been thinking about doing the same thing and am at present cogitating
on some sort of charging choke to use. At present it looks like I am going
to have to have a negotiate with an acquaintance in the transformer winding
business to build one for me.
>
> >
> >
> > 6. Finally, I don't know your background or experience Luc, so I feel
> > obligated to say that your power supply can be very lethal have 12kV
with
> > plenty of current behind it. Good luck, take care and carry on.
>
> Tx I take it like a mark of friendship. I'm near 50 years old, I start to
> fool around with electricity  at 8 Years
> old ( get shock more often than I like ) I learn to be cautious almost
> frightened by high voltage  and I was in
> charge of the engineering section of the film department of a national TV
> station for 10 years. I have the same
> reaction then you when I read post of teens playing with MOT or PIG.
>
> Luc Benard

Yes indeed Luc. You are quite welcome. I tend to be like a mother hen when
it comes to youngsters dealing with electricity. My beginnings and
experience in the electrical/electronic world are very similar to yours. (I
am over 70 now, but my curiosity in the field hasn't dwindled one iota)

Thanks again for the information exchange.

Chuck