Which NEC article addresses emergency power systems?

Which NEC article addresses emergency power systems?

• A. NEC Article 300
• B. NEC Article 725
• C. NEC Article 250
• D. NEC Article 700

Answer: (D)

Emergency power systems require rules that specifically ensure they will operate safely and reliably when normal power is unavailable. NEC Article 700 is dedicated to these systems, covering how emergency power sources (like generators or stored-energy systems) are to be connected, wired, protected, and coordinated with the building’s circuits. It also addresses automatic transfer switches and the interconnections that switch loads from normal power to the emergency source without backfeeding or creating hazards, along with requirements for testing and maintenance. The other articles referenced deal with grounding and bonding (safety paths for fault currents), general wiring methods, or power-limited circuits, none of which govern emergency power systems themselves.

Emergency power systems require rules that specifically ensure they will operate safely and reliably when normal power is unavailable. NEC Article 700 is dedicated to these systems, covering how emergency power sources (like generators or stored-energy systems) are to be connected, wired, protected, and coordinated with the building’s circuits. It also addresses automatic transfer switches and the interconnections that switch loads from normal power to the emergency source without backfeeding or creating hazards, along with requirements for testing and maintenance. The other articles referenced deal with grounding and bonding (safety paths for fault currents), general wiring methods, or power-limited circuits, none of which govern emergency power systems themselves.