RE: 6 MOT Coil

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

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

All I've ever used for ballasting a piglet is series/parallel combinations
of MOTs on each leg of the 240 service. I know this is common and probably
not optimum, but I wonder how it works with big MOT supplies?

I think I've read that MOT core saturation is a problem and the use of
multiple units helps; but I do have many multi MOTs to mess with, not an
option for many, I assume.

I'm thinking that any large-ish power transformer is worth a try. the
secondaries being variously shorted to control current flow. I think I read
that you've removed your MOT shunts Ted. I'm thinking that leaving them in
place is desirable if control is a problem.

[Regarding MOTs and NSTs vis a vis current limiting. MOT limiting does not
approach the severe limiting present in NSTs. This is obvious, but rarely
explicitly stated.]

Can a piglet be used for MOT ballast? I guess that is sort of idiotic.

Finally Ted: "really grunty supply"!?. This makes me laugh. I assume this
means stout?

Who would have thunk that this forum would serve as such a rich cultural
exchange medium!

Dave Hartwick
Chambersburg, PA
USA




Original poster: "tesla by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<tesla-at-paradise-dot-net.nz>

Hi Allan

Enjoyee you post and have emplathy for the difficulty of taking steps
forward.
Yes no doubt about it MOT's are harder to tame but I think when achieved
cheap high power coil is achieved.

To respond to a couple of questions.
My Ballast (two big 11mH chokes) were scored from 50v old technology
rectifier set as used in the Telecoms industry. These rectifier set are
rapidly being replaced by effiecient switch mode PSU and if you have
contacts in the telephone exchange or Microwave repeater siter industries
you might get lucky.
Having said this from Tims post it does seem possible to achieve really big
sparks w/o ballasting if you have a really grunty supply (230v two phase in
the USA I think is needed)

I suspect the size of your MMC might be a little low to achieve optimum
results with MOTs. I use 88nF and I see Tim is around 120nF or more. I'd
agree with you you coil may be a little small if you start to hit it with
more power like 4 to 6 MOT's delivers.

Good luck and care
Ted L in NZ