What is the approximate current in the secondary of a 480:240 volt transformer when the primary current is 100 amps?

To determine the approximate current in the secondary of a 480:240-volt transformer when the primary current is 100 amps, it is important to understand the principle of conservation of power in transformers, which states that the power in the primary side is equal to the power in the secondary side (ignoring losses).

The power can be calculated using the formula:

Power = Voltage × Current

For the primary side of the transformer, with a voltage of 480 volts and a current of 100 amps, the power is:

Power (Primary) = 480 volts × 100 amps = 48,000 watts

On the secondary side, the voltage is 240 volts. To find the current in the secondary winding, we can rearrange the power formula to find the current:

Current (Secondary) = Power (Secondary) / Voltage (Secondary)

Since we know the power should be approximately the same (ignoring losses):

Current (Secondary) = 48,000 watts / 240 volts = 200 amps

This calculation shows that the secondary current is approximately 200 amps when the primary current is 100 amps. This relationship reflects the transformation ratio of the transformer, which in this case is 2:1 (480