The image shows a short-circuit calculation chart also known as a fault current chart for a new construction project where a 150kVA (150,000-volt) dry-type transformer is installed. The transformer (TX) impedance is represented by TX %Z. The chart shows an Available Fault Current (AFC), also known as available short circuit current (ISC) at the secondary spades of the transformer of 16,654 amps.
After leaving the transformer with a single (not parallel) 25-foot run of 500 kCMIL copper conductor in a plastic raceway, the AFC at the end of the run of wire will be 14,741 amps at the electric panel that the transformer supplies.
Notice the comments provided by the electrical engineer at the top of the chart.
Refer to the image:
Which of the following is true?
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