Oklahoma Electrical Practice Exam

What load is considered for branch circuits supplying loads in an electrical system?

1. Resistive Loads

2. Incandescent Loads

3. Inductive Loads

4. Capacitive Loads

The correct answer is: Incandescent Loads

When considering which type of load to account for when sizing branch circuits in an electrical system, incandescent loads are especially relevant. Incandescent loads, typically associated with light bulbs, are primarily resistive in nature. This means that they convert most of the electrical energy they consume directly into light and heat, offering a straightforward calculation of their energy consumption without introducing significant power factor complications. Resistive loads, while closely related, are a broader category that encompasses any load consuming electricity without generating a magnetic field, so they could include devices like electric heaters and toasters. However, in most residential and commercial settings, incandescent bulbs are a common representation of this category because they serve as general-purpose lighting. Inductive loads, such as motors, and capacitive loads, typically found in certain types of equipment and power factor correction devices, are relevant but introduce additional complexity into calculations due to their reactive nature. These types of loads affect the total power factor of a circuit, which isn't the primary consideration when sizing branch circuits for standard residential or commercial lighting circuits. Therefore, focusing on incandescent loads is particularly pertinent in practical scenarios when addressing the standard branch circuits designed to supply lighting in a typical electrical system, making it the ideal point of reference for this question.