Re: x-ray transformer questions

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Original poster: "David Rieben" <drieben-at-midsouth.rr-dot-com> 

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, September 24, 2004 7:52 PM
Subject: x-ray transformer questions


 > Original poster: "Jack Vandam" <snotoir7674g-at-mindspring-dot-com>


Hi Jack,

Since I have some limited experience with x-ray transformers, I'll
try to answer what I can....

 > Hello all once again,
 >
 > Tonight's questions concern a Westinghouse x-ray transformer.  There are
two
 > things I'm wondering about with this unit: its specs and input/ output
 > information.
 >
 > Here's what's on the label:
 > cycles 50/60
 > wiring 3D 8939
 > style 981928
 > Volts AC, KVA, and Amps are all blank.
 > Under the word "Westinghouse", there are the following tiny numbers:
36233-D

I can't really tell much from these part numbers and finding matches
for GE part #s is no easy task.

 > Can anyone figure out the complete specs with this info?
 >
 > Now for the input connections:
 > XFL, XFC, XFS, G, MA, A, AA

 > Input hookup info?
 >

I think the "X" inputs are probably the main primary inputs for
this transformer. Do you know if it's 3-phase? "G" is most likley
ground and I'm not sure what the "M" electrodes are but they're
probably inputs to the filament transformers inside.


 > And, finally, there are two high voltage recessed terminals.  One has a
 > single center conductor; the other side has three (their purpose?).  The
 > diameter of the sockets is 1.25".  I did manage to obtain some high
voltage
 > cable at one point, but the end diameters are too large.  I'm considering
 > making new ends out of epoxy or if I could obtain the correct size cable
 > economically, I would go with that.

That seems a little strange as all of the x-ray trannies that i've seen have
three conductor pins in each of the recessed high voltage terminals. Some
of the sub-100 kV transformers only have one recessed high voltage
terminal but would still have the three electrodes inside. The two extra
electrodes are for the low filament voltage. Sometimes, cable with
the male terminlas that match and fit the female recessed terminlas
of the transformer can be found on ebay but these cables would be
quite expensive if purchased retail.
 >
 > Dimensions are about 13.5x17x15 inches and it must weigh at least 250 lbs
I
 > would guess.  Not sure what I'm going to use it for, but my purpose right
 > now is to just find out about it and get it going, using an appropriate
 > variac for current limiting of course.

At this size, which is rather small for an x-ray tranny BTW, I'd guess
that it's rated around 125 kVp -at- 300 mA, give or take. To properly
current limit it, you will need a reactive ballast in addition to the variac
to be able to push it up to near its maximum rated voltage. X-ray
trannies, just like pole pigs and plate transformers, are not current
limited and can draw a tremendous current if fired up without
proper input ballasting.

You'd need to remove the internal diode sticks if you want
to use it for a Jacob's ladder.
 >
 > If anyone has any info on this or a similar unit, I would appreciate your
 > sharing of it.
 >
 > Thanks,
 > Jack
 >
 >

David Rieben