Electrical Contractor Electrical System Design & Installation Flashcards
6 cards from real Licensed Electrical Contractor practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Electrical Contractor Electrical System Design & Installation flashcards as text
When sizing a transformer for a new commercial installation, which NEC article governs the installation requirements for transformers rated 1000 volts or less?
Answer: Article 450
NEC Article 450 covers the installation requirements for transformers, including overcurrent protection and ventilation requirements.
For a parallel conductor installation using two sets of 500 kcmil conductors per phase, what is the NEC requirement for conductor arrangement?
Answer: Each phase must have the same length, type, and termination method
NEC Section 310.10(G) requires parallel conductors to be the same length, material, circular mil area, insulation type, and termination method.
What is the NEC-required working space clearance in front of a 480V electrical panel?
Answer: 3 feet
NEC Table 110.26(A)(1) requires a minimum of 3 feet of clear working space in front of electrical equipment rated 480V under Condition 1.
When designing an emergency power system for a commercial building, which NEC article specifically covers emergency system requirements?
Answer: Article 700
NEC Article 700 covers emergency systems that are legally required and classified as essential for safety to human life.
In a commercial electrical design, what is the minimum circuit ampacity required for a continuous load per NEC Section 210.20?
Answer: 125% of the continuous load
NEC Section 210.20(A) requires branch circuit conductors to have an ampacity of not less than 125% of the continuous load.
What is the maximum number of disconnecting means permitted for a single service per NEC Section 230.71?
Answer: 6
NEC Section 230.71(A) permits a maximum of six disconnecting means grouped in a single location for each service.