WALMART MAINTENANCE Electrical Systems 2 — Questions and Answers
Question 1: What is the National Electrical Code (NEC)?
- A building design standard
- The US standard for safe electrical installation and maintenance practices (Correct answer)
- A code for emergency communication
- A data encryption standard
Correct answer: The US standard for safe electrical installation and maintenance practices
The NEC (NFPA 70) is the widely adopted US standard that provides guidelines for safe electrical installation, wiring methods, and equipment to minimize fire and shock hazards.
Question 2: LED lighting is replacing fluorescent in many retail stores primarily because:
- LEDs are brighter
- LEDs use less energy, last longer, and require less maintenance (Correct answer)
- LEDs are cheaper to purchase
- Fluorescent lights are illegal
Correct answer: LEDs use less energy, last longer, and require less maintenance
LEDs offer significant advantages in energy efficiency (using 50-70% less energy), lifespan (50,000+ hours vs 20,000), and reduced maintenance costs.
Question 3: What should you do if you smell burning insulation near an electrical panel?
- Open the panel to investigate
- Evacuate the area, de-energize the panel from a safe distance if possible, and call for qualified help (Correct answer)
- Spray water on the panel
- Continue working and monitor the smell
Correct answer: Evacuate the area, de-energize the panel from a safe distance if possible, and call for qualified help
Burning insulation indicates a serious electrical fault that could cause fire or arc flash. The area should be evacuated and power disconnected safely.
Question 4: What is an arc flash hazard?
- A camera flash in the electrical room
- An explosive release of energy caused by an electrical arc between conductors (Correct answer)
- A type of lightning
- A flickering light
Correct answer: An explosive release of energy caused by an electrical arc between conductors
An arc flash is an explosive release of energy that occurs when current flows through air between conductors, producing extreme heat (up to 35,000°F), pressure waves, and intense light.
Question 5: What tool is used to verify that a circuit is de-energized before working on it?
- A flashlight
- A voltage tester or multimeter (Correct answer)
- A screwdriver
- A circuit breaker finder
Correct answer: A voltage tester or multimeter
A voltage tester or multimeter measures voltage to confirm zero energy before work begins. Always test the tester on a known live circuit first to verify it is working.
Question 6: What is the purpose of emergency lighting in a retail store?
- To highlight sale items during power outages
- To illuminate exit paths for safe evacuation during power failures (Correct answer)
- To provide security lighting
- To keep freezers visible during outages
Correct answer: To illuminate exit paths for safe evacuation during power failures
Emergency lighting activates during power failures to illuminate exit routes and emergency exits, enabling safe evacuation of customers and employees.
WALMART MAINTENANCE Electrical Systems 2
What is the National Electrical Code (NEC)?