If a transformer supplies power to a 240-volt, 3-phase, non-continuous 32.841 kVA load, what is the maximum rating for the secondary OCPD?

To determine the maximum rating for the secondary Overcurrent Protective Device (OCPD), it's essential to consider the load and the characteristics of three-phase systems. In a three-phase circuit, the apparent power (in kVA) can be converted into current using the formula:

[ I = \frac{P}{\sqrt{3} \times V} ]

where:

• ( I ) is the current in amps,

• ( P ) is the power in kVA, and

• ( V ) is the voltage line-to-line in volts.

For this specific example, with a load of 32.841 kVA supplied at 240 volts, the calculation can be performed as follows:

1. Convert the kVA to watts: 32.841 kVA is equal to 32,841 VA.

2. Apply the formula:

[ I = \frac{32,841}{\sqrt{3} \times 240} ]

Calculating ( \sqrt{3} ) gives approximately 1.732. Now we can substitute:

[ I = \frac{32,841}{1.732 \times 240} ]

[ I = \frac{32,841}{415.68