Re: Mystery Transformer

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

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bert.hickman-at-aquila-dot-net>

Greg,

Sounds like you have a nice sized control transformer. These are often used
to step down 480/240 vac to 120 volts, or to 24 volts for for control
sections of industrial equipment (to drive relays, lamps, etc.). The
"input" side will be the "H" side. These transformers are typically
constructed with two identical primary windings, the pairs being H1/H2 and
H3/H4. By connecting the windings in parallel (inputs: H1-H3 and H2-H4),
you can run off 240 volts, and in series (H2+H2 tied together and mains
input between H1 and H4) off 480 volts. The output appears to have a
similar configuration allowing parallel or series connections. If nominally
120 vac out, it can be configured to make one nice sized isolation
transformer. If it has nominal 24 volts out, you can configure it to
deliver 6 or 12 volts (or some other voltage with a small variac on the
primary side) to drive a VTTC filament. Nice catch!

-- Bert --
-- 
Bert Hickman
Stoneridge Engineering
Email:    bert.hickman-at-aquila-dot-net
Web Site: http://www.teslamania-dot-com


Tesla list wrote:
> 
> Original poster: "Gregory Hunter by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <ghunter31014-at-yahoo-dot-com>
> 
> Dear List,
> 
> I have a big, fat, E I type transformer I'm hoping you
> can help me identify. It is labeled: "RANDTRONICS
> 143A00379" and "SDS MAGNETICS".  The dimensions are
> 7.5"W, 6.25"H, and 3.5"D.  The core windows are about
> 1.25"W x 3.25"H.  The center leg is about 2.5" x 3.5".
>  It has eight, screw-type terminals, four to a side.
> The terminals on one side are labeled X1 thru X4, and
> on the other side they are labeled H1 thru H4.  The
> thing is painted gloss black.  It appears to be held
> together by a bolt thru each corner--perhaps it can be
> disassembled?  Does anybody know what I've got?  My
> first thought was that I would use the core to wind a
> HV transformer, but I'm afraid the windows are too
> narrow for that.  Comments anyone?
> 
> Best Regards,
> 
> Greg
> 
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