A transformer is used to step down a voltage of 11KV to 220V. Given that the transformer has 3200 turns in the primary, calculate the number of turns in the secondary coil.Another transformer is used to further to step down 220V to 110V. its input current is 3A and the output current is 5.6A. Calculate its efficiency
Q1. Let the number of primary turns Np; number of secondary turns Ns. Let the primary voltage Vp; secondary voltage Vs. Then fundamental transformer theory gives us: Vp/Vs Np/Ns. So: Ns (Vs/Vp).Np i.e.: Ns (220 / 11,000).3200 64. The turns ratio is 50:1 Q2. The product of volts and amps is called the V-A of the transformer: volts x amps. An ideal transformer would generate zero losses in transferring electrical energy from primary winding to the secondary winding. But there is no such thing as an ideal transformer: the transference of energy means that some energy gets lost: in heat, eddy currents and hysteresis losses. For this Q, the input VA 220 x 3 660 V-A, and the output V-A 110 x 5.6 616 V-A. The V-A efficiency (V-A out) ÷ (V-A in) 616 / 660 0.933 93.3 % N.B. This is not the same as the watts efficiency, power in ÷ power out: the V-A efficiency does not take power factor into consideration.
you have fifteen watts moving into, and in basic terms 5 going out, so the customary gadget performance is merely 33%. yet dissimilar the loss arises from themes different than the transformer; specifically, the rectifier gadget will chew up approximately 10% all by ability of itself.
Transformers work at constant voltage/turn ratio, so : V1/n1 V2/n2 n2 n1*V2/V1 3200/11000*220 64.0 turns Eff.cy 100*5.6/6.0 93%
