Re: How long? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sun, 05 Aug 2007 13:32:50 -0700
From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: How long? (fwd)

Hi Tony,

It is dependent on the coil parameters and the components themselves. 
Heat is the killer if a transient voltage doesn't get you first. Area's 
of heat are the spark gap, transformer, capacitors, and interconnect 
wiring. If those items can handle the power applied without 
over-heating, you can run continuously.

On my 4.5" coil using an NST (modified to 10.6kV, 200mA) and a static 
gap (tcbor type), I can run it for several minutes, but I usually run 
about 1 minute as the coil is usually inside the garage. The 4th of July 
I ran it for several 5 minute runs. I noticed the NST and the extension 
cord I ran out in the driveway was warm after the last run. I use a 
Terry Filter and run slightly LTR. I kept the input voltage via a variac 
at about 90% to keep the circuit breaker from tripping (just pulls too 
much current if I crank it up). But still, plenty of spark length at 48 
to 52 inch sparks at 90% variac on Independence Day! Neighbors were 
thrilled and pictures were being flashed!

As far as the coil components, they remained nice and cool (cap, 
secondary, primary). I use 8 awg along the discharge path and small 16g 
hv wire in the charging path.

Here's a schematic of the coil which details the Terry Filter, discharge 
path, etc..
http://www.classictesla.com/photos/ba45/sch45.pdf

Here's photo's of the coil (the Filter has been rebuilt, wiring cleaned 
up, etc.. since)..
Lot's of pics (high speed internet helpful)
http://www.classictesla.com/photos/ba45/ba45.html

Take care,
Bart



Tesla list wrote:

>---------- Forwarded message ----------
>Date: Fri, 3 Aug 2007 21:49:28 -0700
>From: Anthony R. Mollner <penny831@xxxxxxxxxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Subject: How long?
>
>I was wondering if anyone in the group can give some kind of indication of
>how long is safe to run a coil. I am referring to the durability of a static
>gap compared to a SRSG, not to mention the ratings on the capacitors? How
>about between running with or without a terry filter or chokes? Any of the
>frailties that might kill a coil. How long do most of you run your coils at
>one time, 3- seconds, a minute, five even? These tungsten rods should be
>able to just run and run for hours. Comments?
>
>Tony
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