On 7/7/11 12:03 PM, Phil Tuck wrote:
Wow that was news to me, I worked on the principle that the increased current flow through the primary winding must cause more flux to be created in the core. So either that is not the case, which I am not sure why, or it does increase the flux, in which case if it is the latter would the secondary flux increase cancel it out then? Otherwise what is happening?
You've got it, sort of... Consider the transformer with no secondary load...You put a voltage on it, and it has a certain (low) current, with a certain magnetizing flux. The "impedance" seen by the source into the primary is high (which is why the current is low)..
Now start loading the secondary...Current flows in the secondary (and, yes, there is a flux from that), but it's exactly balanced by an increase in the flux in the primary (because there's more current there, too..)
So the net flux in the core is exactly the same. _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla