Re: Transformer Oil

In a message dated 96-02-20 11:49:37 EST, tesla-at-grendel.objinc-dot-com writes:

>I downloaded the COILBLD file and found it extremely helpful.  My
>plans are to build a 6" dia. secondary 24" long with #22 magnet wire.
>First, to clarify the transformer that I have - I had several similar
>questions - It is 12KV -at- .12A sunk in oil.  I am pretty sure it does not
>have any internal current limiting.

Dan,  Nice transformer.

>Can I use a variac to current limit this transformer?  I will be using a
>another variac to vary the input voltage.

As I posted recently, and Richard has before, variacs to not work well for
current limiting.  If you can not get an inductive current limiter like a
welder you should try resistive current limiting.  Try using a few 2000 watt
oven elements in parallel with each other.   I got mine at the St. Vincent
dePaul salvage store.  The only problem with resistive ballasting is the
voltage drop across the resistance will decrease your primary input voltage
and thus the secondary high voltage output.  Most variacs will put out more
than the line voltage in, that will help.

>I am also trying to determine the kind of oil inside this thing.  Does
>anyone know how to tell?  The transformer is in a large metal casing
>and is from around 1948 or so.	It came out of a source unit for a
>spectrograph. (Wondering if it contains PCB's)

If it is 1948 vintage, I would guess it contains PCBs.  I would not open them
>It turns out that I have 2 of these things.  I am planning on paralleling
>them.  This means I will have close to 3KW available.  Is that power
>level still appropriate for a 6" diameter secondary?
>	-Dan

I run my 6" dia coil up to 8 to 9 kva.

Ed Sonderman