# Full load condition of real transformer

1. ### arpansen

4
What is the full load condition of a transformer.

Then in reference to the equation:

Vp = aVs + Req*Ip + jXeq*Ip (the very common complex equation of a simple equivalent circuit )

Should I use Vs= 230 V or Vp = 2300 V in full load load condition or will the magnitude of the primary voltage be greater than 2300 V in full load condition , if it is given that the secondary current is 0.8 power factor(PF) lagging.
if so why??

Last edited: Aug 17, 2014

97
Usually we take VS, Rp, Xp but R’s, X’s and V’L that means the secondary parameters referred to primary. R’s=Rs*np/ns; X’s=Xs*np/ns V’L=VL*np/ns If np/ns=Ep/Es~ Vprated/Vsrated then V’L=VL*Vprated/Vsrated[Vsrated at no-load].
The load p.f. it is cos(fi) –fi the angle between VL and Iload.

97
Correction:
R's=Rs*np^2/ns^2; X's=Xs*np^2/ns^2