What size overcurrent device should be used to protect the primary of a 480/120 volt 15 kVA transformer?

The ratings of a single-phase three-winding transformer are as follows:*primary winding: 300 MVA, 14kV*secondary winding: 300MVA, 200kV*tertiary winding: 40MVA, 20kV. The leakage reactances are:*Xps = 0.1 at 300MVA, 14kV*Xpt = 0.16 at 40MVA, 14kV*Xst = 0.14 at 50MVA, 200kV Neglecting the winding resistance and exciting current, calculate Xp, Xs and Xt using 300 MVA and 14kV as the base for the primary winding.

Why shouldn't rated voltage be applied to the transformer in the inductive strike method?

4. A single-phase, 1000-kVA, 2400/8000-V, 60HZ distribution transformer has the following parameters: Resistance of the 2400-V winding: R1 = 2.75 2 Resistance of the 8000-V winding: R2 = 29.4 2 Leakage reactance of the 2400-V winding: X1= 1.8 Q Leakage reactance of the 8000-V winding: X2 = 20 2 Exciting admittance on the 2400-V side: 0.002 - j0.008 S %3| Draw the equivalent circuit referred to the high voltage side of the transformer. a. b. Draw the equivalent circuit referred to the low voltage side of the transformer. Show the numerical values of impedances on the equivalent circuits. 5. The transformer in Problem 4. is supplying a rated load of 1000-kVA at a rated secondary voltage of 8000 V and at 0.8 power factor lagging. Neglecting the transformer exciting current, determine the input terminal voltage of the transformer on the low-voltage side.

The core loss of a single phase, 230/115 V, 50Hz power transformer is measured from 230 V side by feeding the primary (230 V side) from a variable voltage variable frequency source while keeping the secondary open circuited. The core loss is measured to be 1050 W for 230 V, 50 Hz input. The core loss is gain measured to be 500 W for 138 V, 30 Hz input. The hysteresis and eddy current losses of the transformer for 230 V, 50 Hz input are respectively

The equivalent circuit impedances of a 20-kVA, 8000/240-V, 60-Hz transformer are to be determined. The open-circuit test and the short- circuit test were performed on the primary side of the transformer, and the following data were taken: Open-circuit test (on primary) Short-circuit test (on primary) 8000 V V= 489 V I0.214 A 2.5 A P= 400 W P= 240 W Find the impedances of the approximate equivalent circuit referred to the primary side, and sketch the circuit.

Equivalent circuit parameters R1 = 1ohm, X1 = 2ohm R2 = 0.0035 ohm X2 = 0.0045ohm Xm = 1100ohm Rfe = 6400ohm. The primary voltage of the transformer in idle operation is 220 volts and its secondary voltage is 11 volts. (Xm is magnetizing reactance, Rfe is iron resistance, values ​​indicated by index 1 belong to primary side, values ​​indicated by index 2 belong to secondary side) b. Calculate the idle running iron and magnetizing currents and the efficiency of the transformer in idle operation

What are the objectives of implementing a short circuit test on a single phase transformer?

What does a transformer require on its primary?

What is the KVA rating of the two-winding transformer after conversion as an autotransformer?