RE: HV, oil and air

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Duke, Ronn (CCI-San Diego CCC) by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Ron.Duke-at-cox-dot-com>


Chris,
Air in transformer windings is not quite as critical as in a capacitor.
There are usually only a few hundred volts difference between layers of
windings as opposed to a cap, which would have many thousands of volts
difference between the plates. The coating on the magnet wire will withstand
several hundred volts by itself. Transformers are usually wound with some
sort of treated paper in between layers that increases the voltage standoff.
Transformer builders will usually vacuum down a transformer 2 or 3 times for
18 hours to make sure that the air is out and the oil is in between the
layers. The paper helps this along by letting the oil soak in between the
windings. If the transformer you have came out of an oil bath, than it is
probably already saturated and you wont have a problem. If not, put it in
your custom made housing and cover the core completely with oil. Let it sit
for a week or so to let the oil soak in. You will probably notice the oil
level go down some, just watch it and top it off when needed. I recently
rewound a NST and put it in a modified 30 cal. ammo box. I used Kraft paper
in between layers. After adding the oil, over two weeks time, it absorbed
about 1 pint worth of oil. ( It was a 15/60 NST, it's now a 14/300  SNT) 
 
Keep on Coilin'

Sparky
 

	-----Original Message-----
	From:	Tesla list [SMTP:tesla-at-pupman-dot-com]
	Sent:	Wednesday, April 11, 2001 5:18 PM
	To:	tesla-at-pupman-dot-com
	Subject:	HV, oil and air

	Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<CTCDW-at-aol-dot-com>

	Hello all!

	I have aquired a HV transformer, a tank, and about 4 gallons of
transformer 
	oil. Here's the question..
	I am going to drown this transformer in oil. when they fill pole
transformers 
	with oil, (which does not completely fill them) do they put a vacuum
on the 
	tank to get any air pockets out? I know this is very important for
caps, but 
	I would think that it is just a critical for transofrmers. Any
thoughts?

	Thanks!

	Chris W