Re: MOT Coil operational notes

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

Original poster: "Finn Hammer by way of Terry Fritz <twftesla-at-qwest-dot-net>" <f-h-at-c.dk>

Ted,all

it is a 50Hz system, I assume this is what you have too?

You can see the relationship btwn. mains voltage and the resulting
voltage across the cap.

http://home5.inet.tele.dk/f-hammer/tedNZ.jpeg
To illustrate the chaos, I  made a run of your present settings:

http://home5.inet.tele.dk/f-hammer/tedNZown.jpeg


Cheers, Finn Hammer, Denmark

Tesla list skriver:
 >
 > Original poster: "tesla by way of Terry Fritz <twftesla-at-qwest-dot-net>" 
<tesla-at-paradise-dot-net.nz>
 >
 > Greetings Finn et al
 > Many thanks for your input Finn
 > I'm rushed today but wil look closely at your timings and perhaps contact
 > you off list to clarify some points.
 > Yes you do have the correct notion
 > Firing at top dead centre and then 15deg eithr side.
 >
 > Agree this is very close.
 > This was arrived at after measuing the O/P current spike of >2A that the MOT
 > could deliver.
 >
 > Agree things are chaotic with this system as those ring up voltages would
 > suggest.
 >
 > What I did not understand at first reading re firing times was are these WRT
 > the zero crossing time and was it a 50 or 60Hz system
 >
 > Best
 > Ted L
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Sunday, December 01, 2002 4:07 PM
 > Subject: Re: MOT Coil operational notes
 >
 >  > Original poster: "Finn Hammer by way of Terry Fritz <twftesla-at-qwest-dot-net>"
 > <f-h-at-c.dk>
 >  >
 >  > Ted,
 >  >
 >  > Having done some work on both MOT supplies and 300 BPS systems I dare
 >  > say:
 >  >
 >  > 1) There is nothing about a mot that makes it special in terms of
 >  > magnetics.
 >  >
 >  > 2) You cannot set the electrodes of a 300 BPS SRSG without either a
 >  > simulation package, and a scoped primary circuit for fine tuning. Things
 >  > get really hysterical with these systems, and their behaviour beats
 >  > intuition. At least mine :o)
 >  >
 >  > Am I reading you right, that you have an electrode at -15 deg, top, and
 >  > +15 degrees of the incoming voltage waveform? 15 degrees sound awfully
 >  > close to me.....0.83 mS
 >  >
 >  > Perhaps you will find it interesting to see the timing that I used on
 >  > the Museum coil.
 >  >
 >  > In that setup, the firing af the gaps happens at 2.4mS  6.45mS and
 >  > 8.85mS
 >  >
 >  > http://home5.inet.tele.dk/f-hammer/tesla/museum/setup/setup.htm
 >  >
 >  > I ran a sim of your primary, and came up with these firing points:
 >  >
 >  > 0.2mS  5mS and 7.4mS,
 >  >
 >  > Richie has got some info along these lines:
 >  >
 >  > http://www.richieburnett.co.uk/external.html
 >  >
 >  > but it is getting late so I:
 >  >
 >  > hope this helps, Finn Hammer
 >  >
 >  >
 >  > Tesla list skriver:
 >  >  >
 >  >  > Original poster: "tesla by way of Terry Fritz <twftesla-at-qwest-dot-net>"
 >  > <tesla-at-paradise-dot-net.nz>
 >  >  >
 >  >  > Team
 >  >  > A few observations re 6MOT coil FYI and possible comment re excess Vp
 >  >  >
 >  >  > 88nF/57kHz/6MOT's/Primary ballasting 22mH/6 to 8kVA/300mm x 1200mm
 > toroid/
 >  >  >
 >  >  > 1) ASRG (up to 3000bps) works but not as well as SRSG  (in terms of
 > spark
 >  >  > intensity and length)
 >  >  > 2) Safety gap fires furiously with gap at 12mm with SRSG banging at
 > 300bps
 >  >  > (Vpk+/- 15deg)
 >  >  > 3) 300bps SRSG seems to excite resonance due Cp 88nF and source
 > inductance
 >  >  > of MOT psu. Where else is the excess Vp coming from ?? (see 2 above)
 >  >  > 4) Even with stress of Vp jumping 12mm (6mm per side) MOT's hold
 > up.(oil
 >  >  > baths used)
 >  >  > 5) High bps on ASRG drives streamers near vertical. Ground capacitance
 >  >  > shunts field at high bps ??
 >  >  >
 >  >  > Best
 >  >  > Ted L in NZ
 >  >
 >  >
 >  >