NCCER ELECTRICAL LEVEL 2
GROUNDING AND BONDING EXAM
QUESTIONS WITH CORRECT ANSWERS
NEC Article 250 - Answer-Is the primary governing article for the proper use and
installation of grounding and bonding
short circuit - Answer-a conducting connection, whether intentional or accidental,
between any of the conductors of an electrical system, whether it is from line-to-line or
from line-to-neutral
Ground fault - Answer-as defined in NEC Article 100, is an unintentional, electrically
conducting connection between an ungrounded conductor of an electrical circuit and the
normally noncurrent-carrying conductors
equipment grounding conductor - Answer-the conductive path used to connect the
noncurrent-carrying metal parts of equipment, raceways, and other enclosures to the
system grounded conductor, the grounding electrode conductor, or both.
Grounding systems less than 50v - Answer-grounding is required in the following
situation where supplied by transformers if the supply voltage to the transformer
exceeds 150v to ground
Grounding AC systems over 1kV - Answer-must be grounded if they supply mobile or
portable equipment as covered in NEC Section 250.188
5A ( 50-45=5) - Answer-a single phase system has two legs, Leg A and Leg B. Leg A is
carrying 50A and leg B is carrying 45A, the current carried by the neutral is what
-Lightning,
-voltage surges higher than that for which the circuit is designed - Answer-a grounded
system must limit the voltage on the electrical system and protect it from
Grounding electrode system - Answer-In general, all the following electrodes that are
present must be bonded together to form
steel or iron must be at least 1/4" thick
copper need only be 0.06" (1.5mm) thick - Answer-how thick must plates of iron or steel
how thick must nonferrous metal like copper be
20 ohms or less - Answer-Rod, pipe, and plate electrodes must have a resistance to
ground of__. If not, they must be augmented by an additional electrode spaced not less
than 6' from the first
GROUNDING AND BONDING EXAM
QUESTIONS WITH CORRECT ANSWERS
NEC Article 250 - Answer-Is the primary governing article for the proper use and
installation of grounding and bonding
short circuit - Answer-a conducting connection, whether intentional or accidental,
between any of the conductors of an electrical system, whether it is from line-to-line or
from line-to-neutral
Ground fault - Answer-as defined in NEC Article 100, is an unintentional, electrically
conducting connection between an ungrounded conductor of an electrical circuit and the
normally noncurrent-carrying conductors
equipment grounding conductor - Answer-the conductive path used to connect the
noncurrent-carrying metal parts of equipment, raceways, and other enclosures to the
system grounded conductor, the grounding electrode conductor, or both.
Grounding systems less than 50v - Answer-grounding is required in the following
situation where supplied by transformers if the supply voltage to the transformer
exceeds 150v to ground
Grounding AC systems over 1kV - Answer-must be grounded if they supply mobile or
portable equipment as covered in NEC Section 250.188
5A ( 50-45=5) - Answer-a single phase system has two legs, Leg A and Leg B. Leg A is
carrying 50A and leg B is carrying 45A, the current carried by the neutral is what
-Lightning,
-voltage surges higher than that for which the circuit is designed - Answer-a grounded
system must limit the voltage on the electrical system and protect it from
Grounding electrode system - Answer-In general, all the following electrodes that are
present must be bonded together to form
steel or iron must be at least 1/4" thick
copper need only be 0.06" (1.5mm) thick - Answer-how thick must plates of iron or steel
how thick must nonferrous metal like copper be
20 ohms or less - Answer-Rod, pipe, and plate electrodes must have a resistance to
ground of__. If not, they must be augmented by an additional electrode spaced not less
than 6' from the first
