Re: Problems with Information Unlimited transformer

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Gerald  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

Hi Matt,

If you turn on your transformer driving only the capacitance (no TC primary 
or secondary present, and no sparkgap present),  I can think of only two 
ways to destroy a "good" transformer.  One is if the capacitance is too 
close to resonance with the transformer and with no protection circuit, the 
resonant rise could overvolt the transformer.  Second is if the transformer 
saturates, its effective inductance (I'm assumeing a current limited 
transformer) would decrease and raise the resonant frequency up to the line 
frequency.  Again overvoltage would result.

Indicate the value of your caps are and the type of transformer (also open 
curcuit output voltage and short circuit output current).

Gerry R

> Original poster: Lkeen89@xxxxxxx
> I'm building the BTC3 Tesla coil from Information Unlimited, and tonight 
> we did the first test run of the HV wiring. This step kinda pertains to my 
> situation, so I'll cite it here:
>
> 20: Open up spark gap or place a piece of insulating material between 
> electrodes to prevent firing. Verify proper assembly and plug unit into 
> 115VAC three wire grounded outlet. Check action of S1 (The main power 
> switch), and note the neon indicator light lighting. (It did) Quickly 
> short out the spark gap electrode attached to the capacitor to the chassis 
> ground with the safety probe. Note a loud noisy bright discharge (It did.) 
> Only do this momentarily, as it subjects the components to unusual stress, 
> and only serves to verify proper operation up to this point.
>
> (The actual primary/secondary coils were not attached.)
> (The actual coils are not concerned in this problem. All talk about coils 
> is referring to the transformer.)
>
> Now, here's my problem: As soon as we flipped the switch, there was a bit 
> of sparking inside the secondary of the transformer. We ran through the 
> test as far as grounding it, and it worked just fine, except for the 
> sparking in the transformer. We then shut everything down and attempted to 
> ground the capacitor again to discharge it, to see if it had any residual 
> charge. There was no spark. We were kinda concerned about the spark inside 
> of the transformer, so we turned the coil on again and the transformer 
> started to produce smoke, and there was an orange glow inside of the 
> secondary of the transformer. We tried step 20 again, to ground the 
> capacitor, but with no results. Are there any suggestions as to what might 
> be the problem? I feel that there was an internal problem with the 
> transformer, as we have gone through the wiring several times to verify 
> its accuracy. The coil itself is due next week for a physics project. 
> Could anyone provide any insight?      Thanks, Matt Keen.