Re: Transformer core

In a message dated 10/6/99 5:57:37 AM Eastern Daylight Time, tesla-at-pupman-dot-com 

<< Original Poster: "Matt Behrend" <electronxlc-at-earthlink-dot-net> 
 Hi all,
 I have a large transformer core that I want to wind for my inductive 
 ballast - 13mH.  It must handle 3kVA without saturating, so could 
 some of the transformer experts tell me if my core is large enough, 
 and minimum number of turns required?
 Overall dimensions are 7.5" x 6.25" x 2.5"
 cross sectional area 1.25" x 2.5" on perimeter sides and 2.5" x 
 2.5" in center leg of the El  shape.
 This is from a 1kVA Topaz isolation transformer, but the size of the 
 core seems like it can take much more power.
I'm not an expert on HV or HF stuff, but seems to me all that counts is the 
number of ampere-turns.  This will determine the flux density which causes 
saturation.  Generally, LF uses a larger cores than HF - the slower cycle 
times allows higher flux buildup and saturation.  It would be nice to know 
how many turns were on the original core.