Re: Variable Resistor

>From: wl-god-tw-at-society-dot-com
>Date: Mon, 22 Apr 1996 23:04:44 -0500 
>Subject: Variable Resistor
>To: tesla-at-objinc-dot-com

Matt Ptak asks,
>Has anyone ever used a variable resistor in place of a variac on your
>coils?  I have been having a problem because of blown fuses.  My variac
i>s rated at 120V, 7.5A.  My transformer runs at ups that to 15000V,
>60mA, so when I have the variac at 100V, the transformer tries to draw
>9A and blows the 8A fuse in the variac.  I thought I could use a
>variable resistor in it's place.  I understand that this will vary
>power and wondered what type of effects I will see as opposed to the
>with the variac.

>Matt Ptak
>Sent via WorldLink on 04/22/96 at 23:02:12.
>From: Tidal Wave BBS
>      Altamont, NY
>     The best around!


When the manufacturer puts a 7.5 amp fuse in a 7.5 amp variac it is 
to comply with codes that require this device to run continuously all 
day in and day out at full power without overheating.  The Tesla 
Coiler's credo is to always push a component as hard as possible 
without letting too much of the smoke out.  Your 7.5 amp variac is 
identical to one I have and mine always has a 15 amp fast blow fuse 
installed.  Sometimes it blows but I routinely push this thing safely 
to 10-15 amps for many minutes at a time.  The power cord gets hot,
I should change it for a heavier one, but the variac itself does not heat too
much.  The variac will let you know with a little burning odor when 
you are grossly overloading it.  If this ever happens, check your 
circuit for shorts, or back off on the power.  It will come through 
unscathed.  These things are pretty tough given just a little 

Put in a bigger fuse and push that coil man!  I assume that your 
variac does a slight overvoltage to perhaps 140 volts output with 120 
volts input when the control is dialled all the way up, these are 
common. If that is the case with yours, using a resistor won't be as 
much fun, you won't be able to turn your coil up to eleven!, (the 
neon xfmer should handle this OK, just make sure you don't overvoltage 
your capacitor).

Have fun!

Happy coiling!, rwstephens