Services and Distribution Flashcards
6 cards from real Electrician practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Services and Distribution flashcards as text
What is the purpose of an equipment grounding conductor (EGC)?
Answer: To provide a low-impedance path for fault current to operate overcurrent devices
The EGC provides a low-impedance fault current path back to the source, causing the overcurrent device to trip and clear the fault.
What is a 'separately derived system'?
Answer: A system with no direct electrical connection to the supply side conductors of another system
A separately derived system, such as a transformer secondary, has no direct metallic connection to the supply conductors of another system.
What does 'service entrance' refer to?
Answer: The conductors and equipment that bring power from the utility to the building's main disconnect
The service entrance includes the service conductors, service equipment, and all components between the utility connection and the main disconnect.
What is the purpose of the main bonding jumper in a service entrance panel?
Answer: To connect the neutral bar to the equipment grounding bar
The main bonding jumper connects the grounded (neutral) conductor to the equipment grounding conductor at the service entrance, establishing the ground-neutral bond.
What is the minimum clearance required between service drop conductors and a rooftop that is readily accessible?
Answer: 8 feet
NEC 230.24(A) requires a minimum of 8 feet clearance above a rooftop that is readily accessible to pedestrians and persons on the roof.
What size fuse or breaker is typically used to protect a 200-amp service entrance?
Answer: 200 amps
A 200-amp service is protected by a 200-amp main overcurrent device that matches the rated capacity of the service.