Journeyman Electrician’s Exam Journeyman Electrician's Emergency and Standby Systems 2 — Questions and Answers
Question 1: Under NEC Article 701, Legally Required Standby Systems must restore power within how many seconds of normal power loss?
- 10 seconds
- 30 seconds
- 60 seconds (Correct answer)
- 120 seconds
Correct answer: 60 seconds
NEC 701.12 allows legally required standby systems up to 60 seconds to restore power, compared to the 10-second requirement for emergency systems.
Question 2: Optional Standby Systems covered by NEC Article 702 are primarily intended to:
- Protect life safety during power outages
- Meet government-mandated safety requirements
- Protect private business interests and equipment (Correct answer)
- Supplement legally required standby loads
Correct answer: Protect private business interests and equipment
NEC Article 702 covers Optional Standby Systems, installed voluntarily to protect equipment or business operations rather than by government mandate.
Question 3: NEC Article 708 covers which specialized power system type?
- Emergency Systems
- Legally Required Standby Systems
- Optional Standby Systems
- Critical Operations Power Systems (COPS) (Correct answer)
Correct answer: Critical Operations Power Systems (COPS)
NEC Article 708 covers Critical Operations Power Systems (COPS), designed for facilities vital to national security such as 911 dispatch centers and data centers.
Question 4: Per NEC 700.12(B)(2), the minimum duration for monthly load testing of an emergency generator is:
- 15 minutes
- 30 minutes (Correct answer)
- 60 minutes
- 90 minutes
Correct answer: 30 minutes
NEC 700.12(B)(2) requires monthly testing of emergency generators under load for a minimum of 30 minutes to verify operational reliability.
Question 5: A separate utility service is permitted as an emergency power source under NEC 700.12(D) when:
- The normal service exceeds 400 amperes
- The AHJ approves it and the conductors are adequately protected (Correct answer)
- The building is classified as a high-rise occupancy
- The utility provides a dedicated redundant feed
Correct answer: The AHJ approves it and the conductors are adequately protected
NEC 700.12(D) allows a separate service as an emergency source when the Authority Having Jurisdiction approves and the service conductors are protected from physical damage.
Question 6: NEC 700.3(D) requires periodic testing of emergency systems by a qualified person at intervals not exceeding:
- 7 days
- 30 days (Correct answer)
- 90 days
- 6 months
Correct answer: 30 days
NEC 700.3(D) mandates testing of emergency systems at intervals not exceeding 30 days to ensure the system will operate when needed.
Question 7: Which of the following is a load typically served by a Legally Required Standby System under NEC Article 701?
- Exit and egress lighting
- Ventilation systems in hazardous locations required by the AHJ (Correct answer)
- Residential backup power for household appliances
- Optional UPS systems for office equipment
Correct answer: Ventilation systems in hazardous locations required by the AHJ
Legally required standby loads include ventilation systems in hazardous areas and other loads mandated by governmental authorities that are not immediate life-safety loads.
