RE: Simple Ballast - Photos and data

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

Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Gary.Lau-at-hp-dot-com>

Hi Terry:

Yes, that is indeed me in the photo testing the ballast spool.  As you
reported, the outside was slightly warm, not at all close to being a
concern.  I also tried to feel the inside cylinder of the spool, but it was
inconclusive.  Again, slightly warm, but not clear if the plastic spool was
insulating the surface I touched from the (warmer?) wire on the inside.  My
concern was and is for the inner turns not accessible to touch or
convection cooling.  With no mechanism to remove heat from the inner
layers, their temperature will no doubt go higher than the outer layer.
Short runs are clearly no problem, but as we all know, it's sometimes
difficult to say enough...

I also wanted to go on record for being truly impressed with your
propeller-style RSG construction (see link below).  Folks wanting to build
an RSG may want to consider this.  I think a set screw to lock the rotating
rods in place as well as a shrapnel shield would be wise additions, but
your construction is much simpler than disk-based RSG's.  I also gave the
rotating rod the finger test immediately after your demo.  They were very
warm near the tips, but apparently Tungsten is a poor thermal conductor,
and with so much air flow, the rod near the HDPE arbor (?)  was cool to the
touch.

Regards, Gary Lau
MA, USA


Original poster: "Terry Blake by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<tb3-at-att-dot-net>

Hi Dan,

I started this Tesla stuff about 16 months ago and do not feel like an
expert on the topic.  There are lots opinions and it can be hard to figure
out what is OK and what is a no no.  The gist of most coilers seems to be
that it is OK to run transformers beyond the rating for a short time.  It is
usually a heat build-up sort of thing.  So why not a spool of wire, I ask
you?

I have not done testing on my ballast to see if there are areas inside that
are getting too hot.  The outside never really gets that warm.  I have a
fellow coiler on video (Gary Lau, I think) saying that it is "slightly
warm".  He also tried to put his fingers inside, but did not report
anything.  I'll have to get things set back up and check it out in further
detail for myself..

I have put together a bunch of information about what I am running and video
clips from the tesla event.

Check it out.  All feedback welcome.

http://www.tb3-dot-com/tesla/mrun/index.html


Terry Blake
Coiling in Chicago.