Re: Mot DC Ps

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

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% ).

>
>
> 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 .

> 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.

>
>
> 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.

>
>
> 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.

>
>
>  Chuck

If you have more comment please post it

Luc Benard