Re: Soft transformer turn on without a variac

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Original poster: davep <davep-at-quik-dot-com> 


>which supports Gary. It turns out my solid state relays are "zero crossing"
>on the spec sheet, not phase (like I though) control so that screws up my
>project. It does seem interesting you don't see any solid state relays that
>are 90 degrees off zero crossing or maybe "full voltage crossing"  for
>transformers, or are there any?

         At turn on the 'transformer' is a mostly resistive load.
         (mostly) the resistance of the wire (vector) summed with
         the (small) inductive reactance of the coil as a nearly
         air core coil.  The core does not increase the inductance
         untill the mag field penetrates.

         ( USED to have some scope photos that....)

         best
         dwp

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