Re: multiple gap question

To: tesla-at-pupman-dot-com
Subject: Re: multiple gap question
From: "Megavolt Nick" <tesla-at-fieldfamily.prontoserve.co.uk> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Sun, 13 Feb 2000 11:39:12 -0700
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Hi All,
          the massage below highlights a problem we have in comparing tesla
coils - we don't all quote the same power figures.  In this mail there are 2
power figures you could interpret as the power rating - 10kVA and 3.3kVA.
However neither of these are anything like the power the system is actuall
processing.  The cap is 0.0263湩 and its charged to 14400V (assuming 60Hz
static gapping) break energy = 2.73J therefore the actual power processed is
163 J/sec (or watts).  If I were to post simliar stats for my small coil
 4kVA psu 8kV, 0.054湩 cap) it would seem that i am processing far less
power, however the 1120bps rotary gap means that i I am actually pumping
1935 real watts - more than 10 times the power on a seemingly smaller
system!

I think it would aid clarity in our comparisons if we all quoted the cap
watts rather than the psu rating or wallplug power.  This may involve some
rather complex maths for those using the double bang sync gaps, well that's
not me so......

Regards
Nick Field
> the system is a 10KVA pole pig (240-->14400) running on .0263uF Cap
> (measured) the primary is 3/8" tubing with 3/8" spacing  tapped at 13.2
> turns primary is at 7 degrees inverted conical    secondary is #22 wire
> on an 8X36 form of lexan  wire wound length is 32.75"  Im using 2
> toroids   a small one at 4X18 (odXod) and a 7X26 on top of the smaller
> one..  the distance between top of secondary wind to bottom of first
> toriod is 5.5"   spark gap is the linear opposed "RQ" cooled with the
> output air from a shop vac...   Im using 3 EI cores each wound with #10
> solid copper THHN insulation as inductor current limiters ( reluctance
> gaps vary to have 3 different amp draws) (( 5 amps, 10 amps, and 15
> amps) this gives me various amperage control ( 5,10,15,20,25,30 amps )
> by turning on a combination of 3 switches...
>
> preformance is ...
> 5 amps .. multiple streamers ( 8 - 10") and lots of corona around toroid
> 10 amps... minimal corona at toroid with multiple streamers 24"
> 20amps...  corona at secondary top   36-40" dual streamers  strikes to
> ground rail (dist. is 37" from rail top to top toroid outer dia.)
> 25 amps... less corona at secondary top 40 - 48" dual streamers
> 30 amps... even less corona ( maybe i dont see it any more due to the
> increased lite from the streamers) single streamer ( rare occasion dual)
> 60-70"
>
> the activity of the streamers increases as the power is increased
>
> i have noticed that the previous spark gap ( a single air blown set)
> produced approximately the same results but at about 10% less length but
> the color was more intence ( seemed to be more whitish) ... streamers
> also seemed to be thicker
>
> with the multi gap i have increased length but the streamers are more
> blue/purple and thinner
>
> since i have a modified async to sync motor now ...   im gonna try the
> sync gap setup...   lets see if it is better ;)
>
>
> Scot D
>
>
>