If a feeder circuit has a continuous load of 15A and a noncontinuous load of 10A, what should the feeder overcurrent device be sized at?

To determine the size of the feeder overcurrent device for a circuit with both continuous and noncontinuous loads, it is essential to follow the guidelines provided by the National Electrical Code (NEC). According to NEC 210.20(A), the feeder overcurrent device should be sized based on the maximum continuous load plus a percentage of the noncontinuous load.

In this scenario, there is a continuous load of 15A and a noncontinuous load of 10A. The code requires continuous loads to be calculated at 125% of their value. Therefore, the calculation is as follows:

1. Calculate 125% of the continuous load:

• 15A (continuous load) × 1.25 = 18.75A

2. Add the noncontinuous load, which can be taken at its full value:

• 18.75A (adjusted continuous load) + 10A (noncontinuous load) = 28.75A

Now, since the overcurrent device must be sized to at least this calculated total, the appropriate rating would be the next standard larger size that can accommodate this total load. Since 28.75A is not a standard size for circuit breakers, you would choose the next standard