308 COMPLETE DETAILED CASE STUDY
I. bare conductor included as part of a listed cable assembly
II. metallic cable sheath or armor
III. metallic water piping system - I & II only
Under conditions of maximum ground-fault current flow, an effective equipment grounding system
should ___.
I. incorporate adequate conductance II. not present a fire hazard - both I & II
When visible, the grounding terminal on a wiring device such as a receptacle is ___. - required to be
green in color and must have a hexagonal head or nut
A circuit is installed in EMT and compression fittings are used. A separate EGC is NOT installed in the
conduit. If a ground fault occurs and one or more couplings were never tightened properly, compared to
normal operation, the fault current will be ___ and the OCPD will take ___ time to open. - lower more
Which part of Article 250 covers equipment grounding and equipment grounding conductors? - VI
During periods of ground fault, loose couplings and connectors used in metal conduit systems can cause
a fire hazard. - True
The equipment grounding conductor is sized according to the type of material (copper, aluminum,
copper-clad aluminum) used for the phase conductors and the cross-sectional area of the phase
conductors. - False
For portable tools used in other than residential occupancies, NEC® 250.114(4)(g) Exception allows the
use of ___ in lieu of grounding. - isolation transformers
The resistance of a conductor is inversely proportional to its cross-sectional area. This means that the
resistance ___ as the cross-sectional area of the conductor increases. - decreases
, To avoid arcing and sparking at threaded joints in RMC and IMC, the threads must be ___ before
assembly. - cleaned
During periods of ground fault, a circuit that utilizes large circuit conductors will have a ___ level of fault
current than a circuit with small conductors. - higher
When a circuit is installed in a metal conduit, installation of an ___ equipment grounding conductor
reduces the ground-fault current path impedance and makes it more effective. - internal
Under ground-fault conditions, inductive reactance will exert a powerful influence in directing the return
(fault) current to flow in a path that is ___ the outgoing power ("hot") conductor. - both a & b
When the EMT is used as the EGC for a circuit, its length has no effect on the opening time of the circuit
breaker protecting the circuit. - False
You have installed 465 feet of PVC underground from a breaker panel to a sign. The sign circuit is
protected with a 15-amp breaker. Instead of installing a grounding conductor with the circuit conductors,
could you drive a ground rod at the base of the metal sign and bond the sign to it? - No
Some types of AC and MC cable are furnished with an integral ___ equipment grounding conductor for
the purpose of establishing an isolated ground. - insulated
The equipment grounding conductor is normally ___ in color. - green
NEC® Section 250.119(A)(2) permits an insulated conductor, larger than 6 AWG, of a basic color other
than green to be used as an equipment grounding conductor when which of the following conditions is
satisfied? - The identification encircles the conductor.
NEC® Section 250.118 permits ___ to be used as an equipment grounding conductor. - the armor of Type
AC cable
I. bare conductor included as part of a listed cable assembly
II. metallic cable sheath or armor
III. metallic water piping system - I & II only
Under conditions of maximum ground-fault current flow, an effective equipment grounding system
should ___.
I. incorporate adequate conductance II. not present a fire hazard - both I & II
When visible, the grounding terminal on a wiring device such as a receptacle is ___. - required to be
green in color and must have a hexagonal head or nut
A circuit is installed in EMT and compression fittings are used. A separate EGC is NOT installed in the
conduit. If a ground fault occurs and one or more couplings were never tightened properly, compared to
normal operation, the fault current will be ___ and the OCPD will take ___ time to open. - lower more
Which part of Article 250 covers equipment grounding and equipment grounding conductors? - VI
During periods of ground fault, loose couplings and connectors used in metal conduit systems can cause
a fire hazard. - True
The equipment grounding conductor is sized according to the type of material (copper, aluminum,
copper-clad aluminum) used for the phase conductors and the cross-sectional area of the phase
conductors. - False
For portable tools used in other than residential occupancies, NEC® 250.114(4)(g) Exception allows the
use of ___ in lieu of grounding. - isolation transformers
The resistance of a conductor is inversely proportional to its cross-sectional area. This means that the
resistance ___ as the cross-sectional area of the conductor increases. - decreases
, To avoid arcing and sparking at threaded joints in RMC and IMC, the threads must be ___ before
assembly. - cleaned
During periods of ground fault, a circuit that utilizes large circuit conductors will have a ___ level of fault
current than a circuit with small conductors. - higher
When a circuit is installed in a metal conduit, installation of an ___ equipment grounding conductor
reduces the ground-fault current path impedance and makes it more effective. - internal
Under ground-fault conditions, inductive reactance will exert a powerful influence in directing the return
(fault) current to flow in a path that is ___ the outgoing power ("hot") conductor. - both a & b
When the EMT is used as the EGC for a circuit, its length has no effect on the opening time of the circuit
breaker protecting the circuit. - False
You have installed 465 feet of PVC underground from a breaker panel to a sign. The sign circuit is
protected with a 15-amp breaker. Instead of installing a grounding conductor with the circuit conductors,
could you drive a ground rod at the base of the metal sign and bond the sign to it? - No
Some types of AC and MC cable are furnished with an integral ___ equipment grounding conductor for
the purpose of establishing an isolated ground. - insulated
The equipment grounding conductor is normally ___ in color. - green
NEC® Section 250.119(A)(2) permits an insulated conductor, larger than 6 AWG, of a basic color other
than green to be used as an equipment grounding conductor when which of the following conditions is
satisfied? - The identification encircles the conductor.
NEC® Section 250.118 permits ___ to be used as an equipment grounding conductor. - the armor of Type
AC cable
