Load Calculations & Branch Circuits Flashcards

What is the maximum overcurrent device rating permitted for a branch circuit supplying a 15-ampere receptacle on a single circuit?

Answer: 15 A

A single 15-ampere receptacle on an individual branch circuit must not exceed a 15-ampere overcurrent device.

On a 20-ampere multi-outlet branch circuit, what ampere ratings of receptacles are permitted per NEC Table 210.21(B)(3)?

Answer: 15 or 20 A

A 20-ampere circuit may serve receptacles rated 15 or 20 amperes.

What is the minimum branch-circuit rating for a fixed appliance that is not a motor-operated load rated over 50% of the circuit?

Answer: Equal to or greater than the appliance load

The branch-circuit rating must not be less than the load it supplies.

When a branch circuit supplies a continuous load, the overcurrent device must be rated at least what percent of the continuous load?

Answer: 125%

NEC 210.20(A) requires the OCPD to be sized at 125% of the continuous load.

A bathroom in a dwelling requires a branch circuit of what minimum rating dedicated to its receptacles?

Answer: 20 A

NEC 210.11(C)(3) requires at least one 20-ampere circuit for bathroom receptacle outlets.

What is the calculated load in amperes for a 1500 VA laundry circuit at 120 V?

Answer: 12.5 A

1500 VA / 120 V = 12.5 A.

A 240-volt, 30-ampere branch circuit serving a single fixed appliance can deliver a maximum continuous load of how many amperes?

Answer: 24 A

Continuous loads are limited to 80% of the rating: 30 A x 0.80 = 24 A.