IEC Final Exam Year 1
IEC Final Exam Year 1 Questions and
Answers 2024
What is the result if the neutral wire becomes open on a multiwire circuit having
unequal loads?
a.
The load of higher resistance would overheat and probably be damaged.
b.
The load of lesser resistance would overheat and probably be damaged.
c.
No effect until one load is turned off or opens.
d.
No effect.
a.
The load of higher resistance would overheat and probably be damaged.
Circuits 7 and 9 share a neutral. This is a multiwire branch circuit. If Ckt. 7 is
drawing 13 amps and Ckt. 9 is drawing 16 amps, how much current is flowing in
the neutral?
a.3
b.13
c.29
d.16
IEC Final Exam Year 1
,IEC Final Exam Year 1
3 Amps
The Code reference that specifies the type of disconnecting means (circuit breaker
for example) that can be used on a multiwire branch circuit that feeds devices
mounted on the same yoke [a stack switch or a duplex receptacle for example] is
___.Note: Select N/A (not applicable) if there is not an NEC® requirement.
a.Article 100
b.240.15(B)(1)
c.404.8(A)
d.N/A
b. 240.15(B)(1)
Voltmeters are connected in ___ with the load when used to measure voltage
across a load in a circuit.
Parallel
The neutral has been removed from the neutral bar in the circuit shown in Figure
128.407. Lamp 3 is connected in ___ with Lamps 1 and 2.
Series
(3 wire parallel circuits turn to series when the neutral is disconnected from the
neutral bar)
IEC Final Exam Year 1
,IEC Final Exam Year 1
What is the minimum number of receptacles required in an unfinished basement?
a.2
b.4
c.1
d.0
c. 1
The overall diameter (including insulation) of a 250 kcmil THHN/THWN copper
conductor is ___ inches?
a..082
b..397
c..765
d..711
e..575
d. 711
NEC Chapter 9 Table 5 pg 701
What part of the NEC® is a reference for calculating conduit fill where all
conductors are the same size?
IEC Final Exam Year 1
, IEC Final Exam Year 1
a.Article 100
b.Table 310.15(B)(16)
c.Annex C
d.Table 314.16(A)
c. Annex C
What is the minimum trade size Schedule 80 PVC required to contain four 8 AWG
THHN/THWN copper conductors?
a.1
b.3/4
c.11/4
d.11/2
e.none of these
b. 3/4
NEC Annex C
Eleven #12, five #10, and six #6 THHN/THWN conductors will be installed in a run
of EMT. The smallest trade size EMT you can use is ___.
a.11/2
IEC Final Exam Year 1
IEC Final Exam Year 1 Questions and
Answers 2024
What is the result if the neutral wire becomes open on a multiwire circuit having
unequal loads?
a.
The load of higher resistance would overheat and probably be damaged.
b.
The load of lesser resistance would overheat and probably be damaged.
c.
No effect until one load is turned off or opens.
d.
No effect.
a.
The load of higher resistance would overheat and probably be damaged.
Circuits 7 and 9 share a neutral. This is a multiwire branch circuit. If Ckt. 7 is
drawing 13 amps and Ckt. 9 is drawing 16 amps, how much current is flowing in
the neutral?
a.3
b.13
c.29
d.16
IEC Final Exam Year 1
,IEC Final Exam Year 1
3 Amps
The Code reference that specifies the type of disconnecting means (circuit breaker
for example) that can be used on a multiwire branch circuit that feeds devices
mounted on the same yoke [a stack switch or a duplex receptacle for example] is
___.Note: Select N/A (not applicable) if there is not an NEC® requirement.
a.Article 100
b.240.15(B)(1)
c.404.8(A)
d.N/A
b. 240.15(B)(1)
Voltmeters are connected in ___ with the load when used to measure voltage
across a load in a circuit.
Parallel
The neutral has been removed from the neutral bar in the circuit shown in Figure
128.407. Lamp 3 is connected in ___ with Lamps 1 and 2.
Series
(3 wire parallel circuits turn to series when the neutral is disconnected from the
neutral bar)
IEC Final Exam Year 1
,IEC Final Exam Year 1
What is the minimum number of receptacles required in an unfinished basement?
a.2
b.4
c.1
d.0
c. 1
The overall diameter (including insulation) of a 250 kcmil THHN/THWN copper
conductor is ___ inches?
a..082
b..397
c..765
d..711
e..575
d. 711
NEC Chapter 9 Table 5 pg 701
What part of the NEC® is a reference for calculating conduit fill where all
conductors are the same size?
IEC Final Exam Year 1
, IEC Final Exam Year 1
a.Article 100
b.Table 310.15(B)(16)
c.Annex C
d.Table 314.16(A)
c. Annex C
What is the minimum trade size Schedule 80 PVC required to contain four 8 AWG
THHN/THWN copper conductors?
a.1
b.3/4
c.11/4
d.11/2
e.none of these
b. 3/4
NEC Annex C
Eleven #12, five #10, and six #6 THHN/THWN conductors will be installed in a run
of EMT. The smallest trade size EMT you can use is ___.
a.11/2
IEC Final Exam Year 1
