IBEW Electrical Practice Test 2025 – Complete Exam Preparation

A common cause of overloads in residential circuits is indeed plugging too many devices into a single outlet. This situation occurs because every electrical circuit has a maximum current carrying capacity, which is often determined by the circuit breaker or fuse protecting it. When multiple devices, especially high-draw items like heaters or refrigerators, are plugged into the same outlet, they can draw more current than the circuit can safely handle. This excessive current flow can lead to overheating of wires or components, and potentially cause the circuit breaker to trip or, in more severe cases, lead to electrical fires.

In contrast, options like using LED bulbs or energy-efficient appliances typically do not contribute to overloads; these devices consume significantly less power than their incandescent counterparts or non-efficient appliances. While wiring mistakes can lead to various electrical issues, they are not as directly associated with overloads as the practice of plugging too many devices into a single outlet. Thus, the action of overloading a single circuit by connecting too many devices is the key factor in creating a circuit overload.