[sdiy] Transformer question

[jhaible at debitel.net]

> Thanks for the info. Why does the core have to be sheets of iron
> seperated by an insulating material, and not a solid core? 


You need a ferromagnetic material to make a path of low magnetic
impedance in order to direct the magnetic field the way you want 
it to go (i.e. from your primary to secondary winding, without
much stray field). 
You want to avoid eddy currents (i.e. the ferromagnetic material
acting like secondary windings of low electric impedance), so
you either use a ferrite (not electrically conducting), or
lamination (thin layers of material, that is electrically cunducting
as well as magnetically, separated by thin layers of insulation
to avoid the material forming closed loops above a certain size
for the electric current.)

JH.



-------------------------------------------------
debitel.net Webmail