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Bruce L. Bergman
 
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On Sun, 02 Oct 2005 22:45:15 GMT, "Leo Lichtman"
wrote:
"AL" wrote:


You need a buck boost transformer. A new one
will set you back $100-$150. (clip)

^^^^^^^^^^^^^^^
Maybe you could find a 32 volt transformer with sufficient current rating,
and hook the secondary up to buck line voltage.


Nice idea, but no.

When you hook a transformer up as Buck-Boost you have full primary
line voltage to ground on the secondary windings, so the transformer
you use has to be designed for it. A lot of the surplus transformers
you find are rated B-B, but the nameplate has to be readable, and you
have to dig out the spec sheets and check first.

The cheaper filament transformers that aren't rated for B-B service
will not have the proper insulation on the secondary windings for that
use, and much excitement can happen - think "Fourth Of July Finale".

It might happen the first time you plug it in, or it can wait till
after a few switching transients puncture the insulation. And best of
all it can easily turn into a fire, if you aren't standing there with
a fire extinguisher close at hand...

-- Bruce --

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
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