Grounding and Bonding Flashcards
7 cards from real PC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Grounding and Bonding flashcards as text
What minimum diameter is required for a driven ground rod made of steel or iron per NEC 250.52(A)(5)?
Answer: 5/8 inch
NEC 250.52(A)(5) requires steel or iron ground rods to be at least 5/8 inch in diameter.
In a multi-building installation fed from a single service, which conductor carries fault current back to the source in a subpanel without a neutral-to-ground bond?
Answer: The equipment grounding conductor (EGC)
In a subpanel (separately fed structure), the EGC carries fault current back to the main service where the MBJ provides the return path to the source.
Under NEC 250.119, which color or marking identifies an equipment grounding conductor for conductors larger than #6 AWG?
Answer: Green tape, green paint, or other green marking at terminations
For EGCs larger than #6 AWG, NEC 250.119 allows identification by green tape, green paint, or other green marking at every point where the conductor is accessible.
A plate grounding electrode must expose at least how many square feet of surface area to the soil?
Answer: 2 sq ft
NEC 250.52(A)(7) requires plate electrodes to have at least 2 square feet of surface area in contact with the surrounding soil.
Which bonding method is acceptable for rigid metal conduit (RMC) at a service entrance where the conduit is used as the raceway for service-entrance conductors?
Answer: Listed fittings designed for bonding, grounding bushings, or bonding locknuts
NEC 250.92(B) permits listed fittings, grounding/bonding bushings, or bonding locknuts for bonding service raceways.
When a grounding electrode conductor is spliced, which of the following methods is permitted?
Answer: Irreversible compression connectors listed for grounding or exothermic welding
NEC 250.64(C) requires GEC splices to use irreversible compression connectors listed for grounding or exothermic welding.
What is the purpose of the supply-side bonding jumper (SSBJ) in an electrical system?
Answer: To connect the grounded conductor on the supply side of a disconnecting means to the equipment grounding conductor
The SSBJ connects the grounded (neutral) conductor on the supply side of a service disconnect to the EGC, ensuring fault current return paths for separately derived systems.