Q. What is the maximum allowable primary current of a 2 KVA step-down transformer with a four to one turns ratio if connected across a 440 volt line? 4.5 amps 18.1 amps 27.7 amps None of the given options

Here's how to solve this problem:**1. Determine the secondary voltage:*** The transformer has a 4:1 turns ratio. This means the secondary voltage is 1/4 of the primary voltage.* Secondary voltage = 440V / 4 = 110V**2. Calculate the secondary current:*** The transformer's power rating is 2 kVA (kilovolt-amperes), which is equal to 2000 VA (volt-amperes).* Secondary current (Is) = Power (P) / Secondary voltage (Vs) = 2000 VA / 110V ≈ 18.18 A**3. Calculate the primary current:*** The primary current (Ip) and secondary current (Is) are inversely proportional to the turns ratio.* Ip = Is * (Secondary turns / Primary turns) = 18.18 A * (1/4) ≈ 4.55 A**Therefore, the closest answer is 4.5 amps.** The slight discrepancy is due to rounding during the calculations. The actual primary current is slightly higher than 4.5 amps.