Electrical System Components Flashcards
7 cards from real CEI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Electrical System Components flashcards as text
What is the maximum voltage rating for a standard residential duplex receptacle installed in the US?
Answer: 120V
Standard residential duplex receptacles are rated for 120V use in the US.
Which component in a panelboard provides overcurrent protection for individual branch circuits?
Answer: Circuit breakers
Circuit breakers in a panelboard provide overcurrent protection by tripping when current exceeds rated capacity.
A Type SE (service entrance) cable is primarily used for what application?
Answer: Connecting service equipment to the utility
Type SE cable is designed for use as a service entrance conductor connecting service equipment to the utility supply.
What does the term 'ampacity' refer to in electrical systems?
Answer: The current-carrying capacity of a conductor
Ampacity is the maximum current a conductor can carry continuously without exceeding its temperature rating.
Which type of conduit is NOT suitable for direct burial without additional protection?
Answer: Electrical metallic tubing (EMT)
EMT is not listed for direct burial because its thin walls provide insufficient protection against soil corrosion and physical damage.
In a three-phase, 4-wire wye system, what is the relationship between line voltage and phase voltage?
Answer: Line voltage is 1.73 times phase voltage
In a wye system, line voltage equals phase voltage multiplied by the square root of 3 (approximately 1.732).
What is the purpose of an equipment grounding conductor (EGC) in a branch circuit?
Answer: Provide a low-impedance fault path to facilitate overcurrent device operation
The EGC provides a low-impedance return path for fault current so overcurrent devices will operate quickly and clear faults.