How is full load amps for the secondary side of a transformer (Is) calculated?

The calculation of full load amps for the secondary side of a transformer is crucial for understanding how much current the secondary side will carry under full load conditions. The formula provided in the correct answer effectively combines the apparent power in kilovolt-amperes (KVA) with the secondary voltage to determine the full load current.

In this context, Is represents the secondary current, KVA is the apparent power the transformer can handle, and Es is the secondary voltage. The factor of 1.732 is introduced in the formula to account for three-phase systems, which is common in transformer applications. In this scenario, the equation can be broken down as follows:

1. Multiply the KVA rating by 1000 to convert it to watts, since 1 KVA equals 1000 watts.

2. Divide this result by the secondary voltage (Es), which provides the total current in amps.

3. The 1.732 factor is included to correct the calculation for three-phase systems, reflecting the relationship between line and phase currents.

This formula ensures the result gives the correct representation of current in a three-phase system, which is critical for safe and effective transformer operation.

The other options do not utilize the appropriate conversion for calculating the full load