Breaker Sizing Breakers are typically sized based on the maximum current that the equipment they are protecting will draw. In this case, the generator is rated at 438 kVA. Using the formula: kVA = kW PF, where PF (power factor) is typically assumed to be 0.8 for generators, we get:

kW = kVA / PF = 438 kVA / 0.8 = 547.5 kW

To calculate the maximum current, we use the formula: Current = kW / (Voltage √3) PF. Substituting the given values, we get:

Current = 547.5 kW / (208 V  √3)  0.8 = 1,593 A

Breaker Rating The indicated circuit breaker is rated at 1000 A. This breaker would not be sufficient to protect the generator because it is lower than the maximum current that the generator can draw.

Breaker Selection The correct breaker rating for this generator would be 1600 A (the next standard breaker rating above 1593 A). It is important to select a breaker with a rating that is equal to or greater than the maximum current that the equipment will draw.

Conclusion The 1000 A breaker indicated on the drawings would not be sufficient to protect the generator as it is lower than the maximum current that the generator can draw. The correct breaker rating for this generator would be 1600 A. Breakers are typically sized based on the maximum current that the equipment they are protecting will draw, which can be calculated using the kVA rating and the power factor. Flag for review