Question

An office building has a noncontinuous load subtotal of 10,350 VA and a continuous load subtotal of 18,180 VA. What does the smallest single phase, 240 volt overcurrent protection device REQUIRE?

Answer 1

The smallest single phase, 240 volt overcurrent protection device required is 95 A.

Step-by-step explanation:

To determine the required overcurrent protection device, we need to calculate the maximum current. For the noncontinuous load subtotal of 10,350 VA, we divide it by the voltage to get the maximum current, which is 43.125 A. However, since it is a noncontinuous load, it is subject to a 25% demand factor for overcurrent protection. Therefore, the noncontinuous load requires a minimum overcurrent protection device of 54 A.

For the continuous load subtotal of 18,180 VA, we divide it by the voltage to get the maximum current, which is 75.75 A. Since it is a continuous load, it is subject to an 80% demand factor for overcurrent protection. Therefore, the continuous load requires a minimum overcurrent protection device of 95 A.

Since the maximum value between the noncontinuous and continuous load is 95 A, the smallest single phase, 240 volt overcurrent protection device required is 95 A.