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Old May 1st 12, 04:15 AM posted to rec.radio.amateur.homebrew
raypsi raypsi is offline
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First recorded activity by RadioBanter: Jul 2008
Posts: 242
Default 2.5KVA transformer on square wave 1000hz mains

On Apr 28, 12:21*pm, "Leland C. Scott" wrote:
raypsi,

Running the transformer at 1KHz will likely cook the core. The laminations
will be much too thick at that frequency to keep the eddy current heating to
an acceptable level. Generally the higher the frequency the thinner the
laminations have to be. At some point the core material is changed to
something else, like ferrite, to keep the heating down.

73's

Leland C. Scott
KC8LDO

Hey OM:

I've seen 400 Hz transformers from old air force airplanes it's true
the lamination's are thinner but the physical size per unit power is
1/6 that of a 60 hz transformer. To wit a 2.5 k VA transformer made
for 400 Hz would weigh in at about 6 pounds compared to my Hammond
Canadian made performer at 40 pounds.

Looks like I'm going to be switching 230 v Dc from 2 separate 115 vac
lines on the same side of the main 230 vac line. I'll keep the switch
speed down to 120 Hz Since I found a stacked doubler that gives a
quadruple output. Thus the output capacitor charges twice as fast over
a ladder style multiplier.

Though one fellow ham told me to just buy a 1.5 k VA isolation
transformer to convert 115 to 230 vac. He is a Canadian ham also since
I have a Canadian Transformer.

Thanks for the advise

73 OT
de N8ZU