Two transformers are required for a Scott connection operating from a 440-V, 3- phase supply for supplying two single phase furnaces at 200V on the two- phase side. IF the total output is 150kVA, calculate the secondary to primary turn ratio and the winding currents of each transformer

A small filament transformer has a laminated sheet steel core whose average path length is 20cm and whose cross-sectional area is 5cm2. How many turns must there be on a primary winding to be connected to 120-V 60-Hz source if the flux density is 1.1T (H approximately 600At/m baseon figure 13-14)

In small transformers, the total iron losses may vary from % of the rated output. O 0.5 to 1 O 0.2 to 0.6 O 0.8 to 1.5 O 04 to 1 In DC machine, are collect the current from commutator and given to the external circuit. O Interpoles O Pole shoe O Yoke O Brushes

The rated voltages of a single-phase transformer are 2000 V and 200 V in its primary and secondary respectively. The shunt impedance can be modelled with a resistance of 14000 ohms in parallel with a reactance of 1100 ohm, both refer to primary side. The primary and secondary series impedances are (0.12+j 0.35) ohms and (0.0012+j 0.0035) ohms respectively. A load is connected to the secondary side of transformer, draws 810 KVA with a lagging power factor of 0.85. The load voltage is same as rated voltage, that is 200 V. ▪ Use per unit method for analysis and find the voltage on primary side in pu.

2) 9.2Three - 25 KVA single-phase transformers are connected in delta – delta. One of the transformers has been defected. What is the maximum real power that the transformer bank can deliver at a power factor of 0.8?

The distribution factor for 90 slots, 10-pole, 3-phase winding is A 0.90 B 0.895 C 0.959 D 0.978

Three single phase transformers are connected in a Delta-Wye configuration.  Each transformer is rated 13kV/64kV.  The transformers are connected to a 3 phase 13kV (L-L) supply and the balanced three phase load is 788KVA. What is the current magnitude in the secondary winding of each transformer? explain the steps too please

In no load phasor diagram of practical transformer, the magnetizing current Imag is with flux Ø O Leading by 30° O Lagging by 60° In phase O 90° out of phase

A voltage multiplier has 12 stages Capacitances, all equal to 0.08 μF. Thesupply transformer secondary voltage is 150 kV at a frequency of 100 Hz. Load current 0,006A.What is the percentage ripple, the regulation and the optimum number of stages for minimumregulation or voltage drop.

Open circuit test on transformers is conducted to determine Eddy current losses Copper losses O Hysteresis losses Core losses