NCCER Electrical Module 7 Study Guide Questions and Answers | Latest Version | 2024/2025 | Correct & Verified

NCCER Electrical Module 7 Study Guide Questions and Answers | Latest Version | 2024/2025 | Correct & Verified Why is it important to check the continuity of a circuit before energizing it? Checking continuity ensures that the circuit is complete and free from open connections that could cause a short or system failure when energized. What does a voltmeter measure? A voltmeter measures the potential difference (voltage) between two points in an electrical circuit. What is the purpose of a junction box in an electrical system? A junction box houses wire connections, protecting them from damage and keeping them secure. How do you calculate the power in an electrical circuit? Power is calculated using the formula: P = V × I, where P is power, V is voltage, and I is current. 2 What is a short circuit and how does it occur? A short circuit occurs when there is an unintended path with low resistance, allowing excess current to flow, potentially causing damage or a fire. What is a lighting contactor used for in an electrical system? A lighting contactor is used to control lighting circuits, allowing remote or automated switching of lights. Why is it necessary to follow the National Electrical Code (NEC) in installations? The NEC provides guidelines to ensure electrical systems are safe, efficient, and code- compliant, reducing the risk of accidents and failures. What is the purpose of a disconnect switch in a system? A disconnect switch provides a means to safely isolate a circuit or equipment from its power source for maintenance or emergency purposes. How do you measure current in a circuit? 3 Current is measured by placing an ammeter in series with the circuit to detect the flow of electrical charge. What is the purpose of grounding in an electrical system? Grounding provides a safe path for electricity to flow into the earth in case of a fault, protecting both the system and individuals from electrical shock. Why is it important to size a conductor properly? Proper conductor sizing ensures that it can safely carry the electrical load without overheating or causing a fire hazard. What is the role of a circuit breaker in an electrical system? A circuit breaker interrupts the flow of electricity in case of an overload or short circuit, preventing damage to the system. How does a GFCI (Ground Fault Circuit Interrupter) work? A GFCI detects differences in the current between the hot and neutral conductors and quickly shuts off power to prevent electric shock.