[AMRadio] Ferroresonant transformer revisited


W5OMR/Geoff w5omr at satx.rr.com
Sun May 7 07:14:38 EDT 2006


Jim Candela wrote:

>Rick,
>
>    The ferroresonant transformer is not really
>resonant at all since the winding that feeds the
>capacitor is wrapped around a portion of the core
>that is a saturable reactor. Resonance and saturable
>reactors don't really go together, but in this case we
>do have circulating energy in a ferroresonant
>transformer which consumes about 20% of the VA rating
>of the device. So for a 1 KVA ferroresonant
>transformer the power draw when unloaded may be about
>200 watts, and this is pretty much a constant.
>Therefore with a 1 KVA load, the power input would be
>1.2 kva. Every line cycle runs the core into
>saturation, and this creates eddie core losses, heat,
>buzz, and a quasi square wave output. The output is
>not a sine wave unless yours has a harmonic filter.
>Therefore a true RMS meter is needed to accurately
>measure the AC voltage.
>
>These are really neat devices using very old
>technology.
>

which covers everything *except* what Rick asked, Jim (grinz).

How hot is the darn thing -supposed- to get?  I, too, wouldn't think 
that it's hot enough just sitting there, with no load, that you couldn't 
put your hand on it..

--
-Geoff/W5OMR




More information about the AMRadio mailing list

This page last updated 22 Oct 2017.