Master Examination Practice Drill #1 2011
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Transcript Master Examination Practice Drill #1 2011
Master Electricians
Drill 2011 #9
O 1. After all demand factors have been taken
into consideration for an office building, the
demand load is determined to be 90,000
VA. Where the building has a 120/240 volt,
single-phase electrical system, what
MINIMUM size copper conductors with
THHW insulation are required for the
underground service-lateral conductors?
400 kcmil
B. 350 kcmil
C. 300 kcmil
D. 500 kcmil
A.
Question Answer
1.
D
Reference
NEC PG. #
Tbl. 310.15(B)(16)
Single –phase current
154
Formula
I= Power
Volts
I = 90,000VA = 375 amperes
240 volts
*Note – Size 500 kcmil THHW conductors with
an allowable ampacity of 380 amperes should
be selected.
O 2. A commercial building is to be supplied
with a transformer having a 480Y/277 volt,
3-phase primary and a 208Y/120 volt, 3phase secondary. The secondary will have a
balanced computed demand load of 416
amperes per phase. The transformer is
required to have a MINIMUM kVA rating of
_______.
100 kVA
B. 150 kVA
C. 86 kVA
D. 200 kVA
A.
Question Answer
2.
B
Reference
NEC PG. #
3 – phase power
Formula
VA = I x E x 1.732
O VA = 416 amperes x 208 volts x 1.732
O 149,866 VA ÷ 1,000 = 149.8 kVA
O 3. What is the MINIMUM size equipment
bonding jumper allowed for receptacles
connected to a 20-ampere branch circuit in
a critical care area of a hospital?
8 AWG
B. 10 AWG
C. 12 AWG
D. 14 AWG
A.
Question Answer
3.
B
Reference
NEC PG. #
517.19(C)
444
O 4. The branch circuit conductors supplying
one or more units of information technology
equipment shall have an ampacity of NOT
less than ________ of the connected load.
80 percent
B. 100 percent
C. 115 percent
D. 125 percent
A.
Question Answer
4.
D
Reference
NEC PG. #
645.5 (A)
561
O 5. In Class II, Division I hazardous locations,
an approved method of connection of
conduit boxes is __________.
Compression fittings
B. Threaded bosses
C. Welding
D. All of these
A.
Question Answer
5.
B
Reference
NEC PG. #
502.10(A)(1)(4)
386
O 6. Where a motor of more than 1 horsepower
has a temperature rise of 50°C indicated on
the nameplate, for the purpose of selecting the
overload device, this device shall be selected to
trip at NO more than ________ of the motor’s
full-load ampere rating.
(No exceptions or modifications permitted.)
100 percent
B. 115 percent
C. 125 percent
D. 130 percent
A.
Question Answer
6.
B
Reference
NEC PG. #
430.32(A)(1)
319
O 7. The MINIMUM burial depth for conduit or
cables installed under an airport runway,
concourse or tarmac is ______.
1 ½ feet
B. 2 feet
C. 3 feet
D. 1 foot
A.
Question Answer
7.
A
Reference
NEC PG. #
Tbl. 300.5
138
O 8. Liquidtight flexible metal conduit (LFMC)
is approved for use as an equipment
grounding conductor if it does NOT exceed
_______ in length.
10 feet
B. 12 feet
C. 6 feet
D. 8 feet
A.
Question Answer
8.
C
Reference
NEC PG. #
250.118(6)d.
122
O 9. Conductors supplying more than one (1)
motor shall have an ampacity of NOT less
than ______ of the full-load current rating of
the largest motor in the group and 100% of
the full-load current ratings of all the other
motors in the group.
125 percent
B. 110 percent
C. 150 percent
D. 175 percent
A.
Question Answer
9.
A
Reference
NEC PG. #
430.24(1)&(2)
318
O 10. Determine the MINIMUM size THWN
copper branch-circuit conductors permitted
to supply an ac motor when given the
following related information:
All terminations are rated for 75°C
Nameplate current rating is 25 amperes
15 minute rated motor
Short-time duty
12 AWG
B. 10 AWG
C. 8 AWG
D. 6 AWG
A.
Question Answer
10.
B
Reference
NEC PG. #
430.22(E)
Tbl. 430.22(E)
Tbl.310.15(B)(16)
316
317
154
FLC of motor = 25 amperes x 120% = 30 amperes
* NOTE – Size 10 AWG THWN copper conductors with an
allowable ampacity of the 35 amperes should be selected
O 11. When intermediate metal conduit (IMC)
is threaded in the field, a standard cutting
die with a ________ taper per ft. shall be
used.
3/8 in.
B. 1/2 in.
C. 3/4 in.
D. 1 in.
A.
Question Answer
11.
C
Reference
NEC PG. #
342.28
202
O 12. Apply no exceptions and determine the
MAXIMUM standard size nontime-delay fuse
permitted for branch-circuit, short-circuit,
and ground-fault protection for an ac motor
where given the following related
information:
2 hp – 120 volts, single-phase
Continuous-duty
Nameplate current rating – 22 amperes
No code letter
70 amperes
B. 80 amperes
A.
C. 85 amperes
D. 90 amperes
Question Answer
12.
A
Reference
NEC PG. #
430.6(A)(1)
Tbl. 430.248
240.6(A)
311
337
91
FLC of motor - 24 amperes x 300% = 72 amperes
* NOTE - In this case you must go down to the next standard
size nontime - delay fuse with an ampere rating of 70 amperes
O 13. Which of the following listed is NOT
permitted for sues as both controller and
disconnecting means for a motor?
Inverse time circuit breaker
B. Instantaneous-trip circuit breaker
C. Oil switch
D. Air-break switch
A.
Question Answer
13.
B
Reference
NEC PG. #
430.111(B)(1),(2)&(3)
332
O 14. Under which, if any, of the following
conditions is the neutral conductor to be
counted as a current-carrying conductor?
O I. When it is only carrying the unbalanced
current of a single-phase system
O II. When it is the neutral of a 3-phase wyeconnected system that consists of nonlinear
loads.
I only
B. II only
C. Neither I nor II
D. Both I and II
A.
Question Answer
14.
B
Reference
NEC PG. #
310.15(B)(5)(a)&(c)
152
O 15. Ceiling-suspended luminaires or paddle
fans located ______ or more above the
maximum water level of a spa or hot tub
shall NOT require GFCI protection.
10 feet
B. 7 ½ feet
C. 8 feet
D. 12 feet
A.
Question Answer
15.
D
Reference
NEC PG. #
680.43(B)(1)(a)
587
O 16. A junction box to be installed will contain
the following:
Three – size 6 AWG ungrounded conductors
Three – size 6 AWG grounded conductors
One – size 8 AWG equipment grounding
conductor
Three – size 12 AWG ungrounded conductors
Three – size 12 AWG grounded conductors
One – size 12 equipment grounding conductor
Four – internal clamps
O The junction box is required to have a
volume of at LEAST _______.
A.
B.
51.50 cubic inches
53.75 cubic inches
C. 46.50 cubic inches
D. 56.50 cubic inches
Question Answer
16.
A
Reference
NEC PG. #
Tbl. 314.16(B)
314.16(B)(1)&(2)
179
178
Size 6 AWG ungrounded conductors
3 x 5.00 cu. In. =
15.00 cu.in.
Size 6 AWG grounded conductors
3 x 5.00 cu. In. =
15.00 cu.in.
Size 8 AWG grounding conductors
1 x 3.00 cu.in. =
3.00 cu.in.
Size 12 AWG ungrounded conductors
3 x 2.25 cu.in. =
6.75 cu.in.
Size 12 AWG grounded conductors
3 x 2.25 cu.in. =
6.75 cu.in.
Size 12 AWG grounding conductors
Internal clamps
-0-
1 x 5.00 cu.in. =
Total =
5.00 cu.in.
51.50 cu.in.
O 17. Where conductors of size 4 AWG or
larger are installed in conduits entering a
junction box and straight pulls of the
conductors are to be made, the length of the
box shall NOT be less than _______ times
the trade of the largest raceway.
Six
B. Eight
C. Ten
D. Twelve
A.
Question Answer
17.
B
Reference
NEC PG. #
314.28(A)(1)
183
O 18. With respect to service-drop conductors
and open overhead wiring of not more than
750 volts to ground, the MINIMUM vertical
clearance that must be maintained from the
base of a swimming pool diving board and
the conductors is _________.
14 ½ feet
B. 16 ½ feet
C. 20 ½ feet
D. 22 ½ feet
A.
Question Answer
18.
D
Reference
NEC PG. #
680.8(A)
Fig. 680.8
Tbl. 680.8
577
578
578
O 19. The life safety branch of the emergency
system of a health care facility shall provide
power to ______.
O I. automatic doors used for building egress
O II. Illuminate electrical equipment
I only
B. II only
C. Both I and II
D. Neither I nor II
A.
Question Answer
19.
A
Reference
NEC PG. #
517.32(H)
448
O 20. When a building contains _______, the
building may have more than one service
without special permission being granted
from the local authority having jurisdiction.
Exit lights
B. Fire pumps
C. Computers
D. Four-hour rated fire-resistant walls
A.
Question Answer
20.
B
Reference
NEC PG. #
230.2(A)(1)
78
O 21. In general, service-drop conductors shall
have a vertical clearance of at LEAST
_______ above the roof surface of a building
having no overhang.
10 feet
B. 12 feet
C. 14 feet
D. 8 feet
A.
Question Answer
21.
D
Reference
NEC PG. #
230.24(A)
80
O 22. In general, the phase arrangement on
the three-phase busses for a three-phase
panelboard or switchboard shall be A, B, C,
as viewed from __________.
O I. Back to front
O II. Bottom to top
I only
B. II only
C. Neither I nor II
D. Both I and II
A.
Question Answer
22.
C
Reference
NEC PG. #
408.3(E)
274
O 23. Where a conductor is marked RHW-2 on
the insulation what does the -2 represent?
The cable has 2 conductors.
B. The conductor is double insulated
C. The conductor has a nylon outer jacket
D. The conductor has a maximum operating
temperature of 90°C
A.
Question Answer
23.
(D)
Reference
NEC PG. #
Tbl. 310.104(A)
168
O 24. Which of the following listed raceways is
NOT permitted for use of enclosing control
wiring for electric motor-driven fire pumps?
Flexible metal conduit (FMC)
B. Liquidtight flexible metal conduit (LFMC)
C. Liquidtight flexible nonmetallic conduit
(LFNC)
D. Intermediate metal conduit (IMC)
A.
Question Answer
24.
A
Reference
NEC PG. #
695.14(E)
620
O 25. In a hospital, low-voltage equipment that
is frequently in contact with the bodies of
persons, must operate on a voltage of _____
or less or be moisture resistant, double
insulated or approved as intrinsically safe.
10 volts
B. 24 volts
C. 50 volts
D. 120 volts
A.
Question
Answer
Reference
NEC PG. #
25.
A
517.65(A)(1),(2)&(3)
455
O 26. A grounding electrode that is the sole
connection to the made grounding
electrode, shall NOT be required to be larger
than size _____ copper conductor.
1/0 AWG
B. 6 AWG
C. 4 AWG
D. 3/0 AWG
A.
Question Answer
26.
B
Reference
NEC PG. #
250.66(A)
115
O 27. For solar photovoltaic systems, locating
the system grounded connection point as
close as practicable to the photovoltaic
source better protects the system from
_________.
Excessive voltage drop
B. Excessive resistance in the grounding
system
C. Voltage surges due to the lighting
D. Voltage surges due to ground-faults
A.
Question Answer
27.
C
Reference
NEC PG. #
690.42,IN
603
O 28, Transformers containing oil or a liquid
that will burn where located in Class I,
Division 1 locations shall be _______.
Enclosed in a fence
B. Installed in vaults only
C. Identified for Class I locations
D. Installed in a fire-resistant room
A.
Question Answer
28.
B
Reference
NEC PG. #
501.100(A)(1)
381
O 29. Where liquidtight flexible metal conduit
(LFMC) is installed in a Class I, Division 2
hazardous location, it shall be permitted to
delete the bonding jumper, where the LFMC
is NOT longer than _______ and the
overcurrent protection in the circuit is limited
to _______ or LESS and the load is not a
power utilization load.
6 feet – 20 amperes
B. 10 feet – 10 amperes
C. 6 feet – 10 amperes
D. 6 feet – 15 amperes
A.
Question Answer
29.
C
Reference
NEC PG.
#
501.30(B),Ex.(1)&2
381
O 30. Which one of the following wiring
methods is permitted to be installed in ducts
specifically fabricated for environmental air?
Rigid polyvinyl chloride conduit (PVC)
B. Electrical metallic tubing (EMT)
C. Armored Cable (AC)
D. Nonmetallic sheathed cable (NM)
A.
Question Answer
30.
B
Reference
NEC PG. #
300.22(B)
144
O 31. An adjustable overload protection device
protecting a single phase, 240-volt,
continuous-duty, 5 hp, ac motor with a FLA
rating of 26 amperes and a temperature rise
of 50°C marked on the nameplate, shall be
selected to trip at NOT more than ______.
(Consider the value you select will enable
the motor to start without tripping and
modification of this value is not necessary)
29.9 amperes
B. 32.2 amperes
C. 33.8 amperes
D. 36.4 amperes
A.
Question Answer
31.
A
Reference
NEC PG. #
430.6(A)(2)
Tbl.430.248
430.32(A)(1)
312
337
319
FLA of motor = 26 amperes x 115% = 29.9 amperes
O 32. In Class II, Division 1 locations, where
pendant mounted luminaires are suspended
by rigid metal conduit (RMC) and a means
for flexibility is not provided, the RMC shall
have a length of NOT more than ________.
12 inches
B. 18 inches
C. 24 inches
D. 30 inches
A.
Question Answer
32.
A
Reference
NEC PG. #
502.130(B)(4)
390
O 33. A commercial kitchen is to have the
following cooking related equipment
installed:
One – 14 kW range
One – 5.0 kW water heater
One – 0.75 kW mixer
One – 2.5 kW dishwasher
One – 2.0 kW booster heater
One – 2.0 kW broiler
O Determine the demand load, in kW, after
applying the demand factors for the kitchen
equipment.
19.00 kW
B. 26.25 kW
A.
C. 18.38 kW
D. 17.06 kW
Question Answer
33.
A
Reference
NEC PG. #
220.56
Tbl.220.56
65
67
14.00 kw – range
5.00 kw - water heater
0.75 kw – mixer
2.50 kw – dishwasher
2.00 kw – booster heater
2.00 kw – broiler
26.25 kw – total connected load x 65% = 17.06
•
•
NOTE – However the NEC ® states the demand shall
not be less than the two largest pieces of equipment.
14.00 kw + 5.00 kw = 19 kw demand
O 34. In a minor repair commercial garage,
any unventilated pit or below-grade work
area is classified as a _______ hazardous
location, where gaseous liquids and fuels
are not transferred.
Class I, Division 2
B. Class II, Division 1
C. Class II, Division 2
D. Class I, Division 1
A.
Question Answer
34.
A
Reference
NEC PG. #
511.3(D)(3)(b)
421
O 35. Where a motor controller enclosure is
located outdoors and is subject to be
exposed to sleet, it shall have a MINIMUM
rating of _______, where the controller
mechanism is required to be operable when
ice covered.
Type 3
B. Type 3S
C. Type 3R
D. Type 3SX
A.
Question Answer
35.
B
Reference
NEC PG. #
Tbl. 110.28
41
O 36. When buried raceways pass under a
commercial driveway or parking lot the
MINIMUM cover requirements ______.
Decrease if installed in rigid metal conduit
(RMC)
B. Do not change in regard to wiring methods
used
C. Shall be increased for direct-buried cables
D. Shall be increased, decreased or remain
the same, depending on the wiring method
used
A.
Question Answer
36.
B
Reference
NEC PG. #
Tbl. 300.5
138
O 37. The National Electrical Code® requires
ventilation of a battery room where batteries
are being charged to prevent ___________.
Battery corrosion
B. Electrostatic charge
C. Deterioration of the building steel
D. An accumulation of an explosive mixture
A.
Question Answer
37.
D
Reference
NEC PG. #
480.9(A)
360
O 38. For other than Design B energy-efficient
motors, where the setting specified in Table
430.52 of the NEC® is not sufficient for the
starting current of the motor, the setting of
an instantaneous trip circuit breaker shall
be permitted to be increase3d, but in NO
case exceed ________ of the full-load
current of the motor.
1300 percent
B. 1700 percent
C. 1100 percent
D. 800 percent
A.
Question Answer
38.
A
Reference
NEC PG. #
430.52(C)(3), Ex.1
323
O 39. Where given the following related
information, determine the MAXIMUM standard
size overcurrent protection required for the
primary and secondary side of a transformer,
when primary and secondary overcurrent
protection is to be provided.
150 kVA rating
Primary – 480 volt, 3-phase, 3-wire
Secondary – 208Y/120 volt, 3-phase, 4-
wire
A.
B.
C.
D.
Primary – 500 amperes, Secondary – 500
amperes
Primary – 450 amperes, Secondary – 600
amperes
Primary – 500 amperes, Secondary – 450
amperes
Primary – 450 amperes, Secondary – 500
amperes
Question Answer
39.
B
Reference
NEC PG. #
3 – Phase Current
Formula
450.3(B)
Tbl. 450.3(B)
240.6(A)
348
349
91
(Primary)
I=
VA___ I = __150,000__ = 150,000 = 180 amps x 250% = 450 amps
E x 1.732
480 x 1.732
831.36
(Secondary )
I=
VA___ I = __150,000__ = 150,000 = 416 amps x 250% = 520 amps
E x 1.732
208 x 1.732
36.25
O 40. For capacitors of over 600 volts, a
means shall be provided to reduce the
residual voltage of a capacitor to ________
after the capacitor is disconnected from the
source of supply.
50 volts or less within 1 minute
B. 24 volts or less within 1 minute
C. 50 volts or less within 10 minutes
D. 50 volts or less within 5 minutes
A.
Question Answer
40.
D
Reference
NEC PG. #
460.28(A)
358
O 41. Apply no exceptions and determine the
MAXIMUM standard size time-delay fuses
permitted to be used for branch-circuit,
short-circuit, and ground-fault protection for
a 15 hp, 480-volt, three-phase, continuousduty, wound rotor motor.
35 amperes
B. 40 amperes
C. 50 amperes
D. 55 amperes
A.
Question Answer
41.
A
Reference
NEC PG. #
430.6(A)(1)
Tbl. 430.250
Tbl. 430.52
240.6(A)
311
338
323
91
FLC of motor = 21 amperes x 175% = 36.75 amperes
* NOTE – In this situation you are required to go DOWN to
the next standard size fuses with a rating of 35 amperes
O 42. In general, when conductors of different
insulation rating are installed in a common
raceway and the voltage is 600 colts or less,
the NEC® requires __________.
All conductors shall have an insulation
rating equal to at least the maximum circuit
voltage applied to any conductor on the
raceway
B. The conduit allowable fill to be limited to 31
percent
C. All conductors within the raceway shall have
a temperature rating of 75°C
D. The insulation of the lower rated conductors
to be identified with blue or yellow colors.
A.
Question Answer
42.
A
Reference
NEC PG. #
300.3(C)(1)
136
O 43. Where used outdoors, aluminum
grounding conductors shall NOT be
terminated within _____ of the earth.
18 inches
B. 24 inches
C. 3 feet
D. 6 feet
A.
Question Answer
43.
A
Reference
NEC PG. #
250.64(A)
113
O 44. A 6,000 sq. ft. bank building is to be
constructed and the number of generalpurpose receptacles to be installed in the
building is yet to be determined; the building
will also have an electric sign. Determine the
MINIMUM number of 120-volt, 20-ampere
branch circuits required for the lighting,
receptacles and the sign.
12
B. 13
C. 14
D. 15
A.
Question Answer
44.
D
Reference
NEC PG. #
Art. 100
210.19(A)(1)
Tbl. 220.12
600.5(A)
27
52
63
519
6000 sq. ft. x 3.5 VA = 21,000 VA x 125% = 26,250 VA (lighting )
6000 sq. ft. x 1.0 VA =
6,000 VA (receptacles)
32,250 VA ( recpts. & ltg.)
120 volts x 20 amperes = 2,400 VA of one circuit
32,250 VA (load)/2,400 VA (one circuit) = 13.4 ckts. = 14 circuits
14 circuits ( lighting & receptacles) + 1 sign circuit = 15 circuits total
O 45. Enclosures containing circuit breakers,
switches and motor controllers located in
Class II, Division 2 locations, shall be ______
or otherwise identified for the location.
Gastight
B. Vapor-proof
C. Dust tight
D. Stainless steel
A.
Question Answer
45.
C
Reference
NEC PG. #
502.115(B)
388
O 46. Where installed for a commercial
occupancy, determine the MINIMUM size
THWN copper conductors required from the
terminals of a 3-phase, 480Y/277 volt, 4wire, 200 kW generator to the first
distribution device(s) containing overcurrent
protection, where the design and operation
of the generator does NOT prevent
overloading.
250 kcmil
B. 300 kcmil
C. 400 kcmil
D. 500 kcmil
A.
Question Answer
46.
B
Reference
NEC PG. #
3 – Phase current
Formula
455.13
Tbl. 310.15(B)(16)
347
154
I = kW x 1,000
I = 200 x 1,000 = 200,00 = 240.56 amperes (FLC)
volts x 1.732
480 x 1.732
831.36
241 amperes x 115% = 277 amperes (required ampacity of conductors)
*NOTE – Size 300 kcmil THWN conductors with an allowable
ampacity of 285 amperes should be selected.
O 47. Where required, conduit seals installed
in Class I Divisions 1 & 2 locations shall
have the minimum thickness of the sealing
compound not less than the trade size of
the sealing fitting and, in NO case less than
_______ thick.
1/2 in.
B. 5/8 in.
C. 3/4 in.
D. 1 in.
A.
Question Answer
47.
B
Reference
NEC PG. #
501.15(C)(3)
379
O 48. A dwelling unit to be built will have
1,400 sq. ft. of livable space on the main
floor, a 1,400 sq. ft. basement (unfinished
but adaptable for future use), a 200 sq. ft.
open porch and a 600 sq. ft. garage.
Determine the MINIMUM number of 15ampere, 120-volt general lighting branchcircuits required for the dwelling.
Four
B. Five
C. Six
D. Seven
A.
Question Answer
48.
B
Reference
NEC PG. #
220.12
Tbl. 220.12
61
63
1,400 sq. ft. + 1,400 sq. ft. = 2,880sq. Ft. x VA = 8,400 VA
120 volts x 15 amperes = 1,800 VA of one circuit
8,400 VA (load)
4.6 = 5 circuits total
1,800 VA ( one circuit)
O 49. The optional method of feeder and
service load calculations for dwelling units is
reserved for feeder and service conductors
with a MINIMUM ampacity of ________ or
greater.
400 amperes
B. 200 amperes
C. 150 amperes
D. 100 amperes
A.
Question Answer
49.
D
Reference
NEC PG. #
220.82(A)
67
O 50. In an industrial establishment, what is
the MAXIMUM length of 200 ampere rated
busway that may be tapped to a 600
ampere rated busway, without additional
overcurrent protection?
10 feet
B. 25 feet
C. 50 feet
D. 75 feet
A.
Question Answer
50.
C
Reference
NEC PG. #
368.17(B),Ex.
225
O 51. Thermal insulation is not permitted to be
installed above a recessed luminaire or
WITHIN _____ of the recessed luminaire’s
enclosure, wiring compartment, ballast,
transformer, LED driver or power supply,
unless the luminaire is identified as Type IC
for insulation contact.
3 inches
B. 4 inches
C. 6 inches
D. 8 inches
A.
Question Answer
51.
A
Reference
NEC PG. #
410.116(B)
286
O 52. What is the MINIMUM height allowed for
a fence enclosing an outdoor installation of
2,400 volt electrical equipment?
6 feet
B. 7 feet
C. 8 feet
D. 9 feet
A.
Question Answer
52.
B
Reference
NEC PG. #
110.31
40
O 53. All exposed non-current-carrying metal
parts of an information technology system
shall ______ or shall be double insulated.
Be bonded to the equipment grounding
conductor
B. Not be bonded to the equipment grounding
conductor
C. Be bonded to the grounded conductor
D. Be isolated
A.
Question Answer
53.
A
Reference
NEC PG. #
645.15
562
O 54. Storage batteries used as a source of
power for emergency systems shall be of a
suitable rating and capacity to supply and
maintain the total load for at
LEAST________.
1/2 hour
B. 1 hour
C. 1 ½ hour
D. 2 hours
A.
Question Answer
54.
C
Reference
NEC PG. #
700.12(A)
624
O 55. Circuit breakers rated at _____ or less
and 600 volts or less shall have the ampere
rating molded, stamped, etched or similarly
marked into their handles or escutcheon
areas.
600 amperes
B. 200 amperes
C. 400 amperes
D. 100 amperes
A.
Question Answer
55.
D
Reference
NEC PG. #
240.83(B)
96
O 56. What percent of electrical supplied
spaces in a recreational vehicle park must
be equipped with at least one (1) 30-ampere
125-volt receptacle outlet?
75 percent
B. 60 percent
C. 70 percent
D. 100 percent
A.
Question Answer
56.
C
Reference
NEC PG. #
551.71
500
O 57. A straight pull of size 250 kcmil and 350
kcmil conductors is to be made in a junction
box that will have one (1) 3 in. conduit and
two (2) 2 ½ in. conduits entering on the
same side and exiting on the opposite wall.
No splices or terminations will be made in
the box. Which of the following listed
junction boxes is the MINIMUM required for
this installation?
18 in. x 12 in.
B. 20 in. x 18 in.
C. 20 in. x 20 in.
D. 24 in. x 24 in.
A.
Question Answer
57.
D
Reference
NEC PG. #
314.28(A)(1)
183
3 in. (largest conduit) x 8 = 24 in.
O 58. Where conduits enter a floor-standing
switchboard or panelboard at the bottom,
the conduits, including their end fittings,
shall NOT rise more than _______ above the
bottom of the enclosure.
6 inches
B. 3 inches
C. 2 inches
D. 4 inches
A.
Question Answer
58.
B
Reference
NEC PG. #
408.5
275
O 59. A bonding jumper connected between
the communications grounding electrode
and power grounding electrode system at
the building or structure service where
separate electrodes are used shall NOT be
smaller than ______ copper.
8 AWG
B. 6 AWG
C. 12 AWG
D. 10 AWG
A.
Question Answer
59.
B
Reference
NEC PG. #
800.100(D)
674
O 60. Which of the following listed copper
conductors, is the MINIMUM size 75°C
rated conductors required to supply a
continuous-duty, 25 hp, 208-volt, 3-phase
motor, where the motor is on the end of a
short conduit run that contains only three
(3) conductors, at an ambient temperature
of 115°F?
1 AWG THWN
B. 2 AWG THWN
C. 1 AWG THHN
D. 1/0 AWG THWN
A.
Question
Answer
Reference
NEC PG. #
60.
A
430.22
Tbl. 430.250
Tbl. 310.15(B)(16)(a)
Tbl. 310.15(B)(16)
316
338
150
154
25 hp motor FLC = 74.8 amperes x 125% = 93.5 amperes
93.5 amperes ÷ .75 (temperature correction) = 124.6 amperes
* NOTE – The wire size needs to be increased because of the
elevated ambient temperature. Size 1 AWG THWN conductors with
allowable ampacity of 130 amperes should be selected
O 61. Single-conductor cable Type ______
shall be permitted in exposed outdoor
locations in photovoltaic source circuits for
photovoltaic module interconnections within
the photovoltaic array.
UF
B. THHN
C. USE-2
D. THWN
A.
Question Answer
61.
C
Reference
NEC PG. #
690.31(B)
601
O 62. For track lighting installed in a retail
store, a MAXIMUM of two (2) feet of lighting
track or fraction thereof shall be considered
______.
150 VA
B. 180 VA
C. 200 VA
D. 100 VA
A.
Question Answer
62.
A
Reference
NEC PG. #
220.43(B)
64
O 63. Where fixed wiring above bulk fuel
storage tanks is installed in PVC conduit, the
PVC shall be Schedule ________.
20
B. 40
C. 80
D. 100
A.
Question Answer
63.
C
Reference
NEC PG. #
515.7(A)
429
O 64. Disregarding exceptions, the MINIMUM
size grounded or undergrounded conductors
permitted to be connected in parallel is
_____.
6 AWG
B. 1 AWG
C. 2 AWG
D. 1/0 AWG
A.
Question Answer
64.
D
Reference
NEC PG. #
310.10(H)(1)
429
O 65. In general, 4 in. wide underfloor
raceways shall have a covering of wood or
concrete of NOT less than _______ above
the raceway.
½ in.
B. ¾ in.
C. 1 in.
D. 1 ¼ in.
A.
Question Answer
65.
B
Reference
NEC PG. #
390.4(A)
238
O 66. Exposed trade size ¾ in. Schedule 40
PVC conduit is required to be securely
supported at intervals NOT to exceed
_______.
3 feet
B. 4 feet
C. 6 feet
D. 8 feet
A.
Question Answer
66.
A
Reference
NEC PG. #
352.30(B)
Tbl. 352.30
209
210
O 67. Receptacles located within the patient
care areas of pediatric wards shall be
______ or shall employ a listed tamperresistant cover.
15 ampere rated
B. Provided with GFCI
C. A single receptacle type
D. Listed tamper-resistant
A.
Question Answer
67.
D
Reference
NEC PG. #
517.18(C)
444
O 68. What is the MAXIMUM length permitted
of a flexible cord that may be used to cordand-plug connect a water circulating pump
motor for a swimming pool at a dwelling?
3 feet
B. 4 feet
C. 6 feet
D. 10 feet
A.
Question Answer
68.
A
Reference
NEC PG. #
680.21(A)(5)
579
O 69. The MAXIMUM height above the floor or
working platform to the center of the
operating handle of a service disconnecting
switch when it is in the ON position must not
exceed ______.
6 feet
B. 6 ft. 6 in.
C. 6 ft. 7 in.
D. 7 feet
A.
Question Answer
69.
C
Reference
NEC PG. #
404.8(A)
267 & 268
O 70. The upward discharging vent of an
underground fuel tank of motor fuel
dispensing facilities is classified as a Class I,
Division 1 location WITHIN ______ of the
open vent.
3 feet
B. 5 feet
C. 6 feet
D. 8 feet
A.
Question Answer
70.
B
Reference
NEC PG. #
Tbl. 514.3(B)(1)
427
O 71. Flexible metallic tubing (FMT) shall NOT
be used in lengths exceeding _______.
5 feet
B. 6 feet
C. 8 feet
D. 10 feet
A.
Question Answer
71.
B
Reference
NEC PG. #
360.12(6)
219
O 72. Unless approved for a higher voltage,
surface nonmetallic raceways are NOT
approved where the voltage is ______ or
more between conductors.
120 volts
B. 150 volts
C. 300 volts
D. 250 volts
A.
Question Answer
72.
C
Reference
NEC PG. #
388.12(3)
237
O 73. What is the MINIMUM permitted sill
height of a transformer vault doorway?
2 inches
B. 8 inches
C. 6 inches
D. 4 inches
A.
Question Answer
73.
D
Reference
NEC PG. #
450.43(B)
354
O 74. PVC conduit used exposed in areas of
physical damage shall be ________.
Type Schedule 80
B. Type Schedule 40
C. Type Schedule 100
D. Prohibited
A.
Question Answer
74.
A
Reference
NEC PG. #
352.10(F),IN
209
O 75. Determine the MAXIMUM setting
permitted for the overload protection for a 7
½ hp, 3-phase, 480 volt, induction-type ac
motor with a full-load current of 15
amperes, an 86% power factor, and a
service factor of 1.00 indicated on the
nameplate. (Assume exceptions and
modifications are not to be applied.)
17.25 amperes
B. 12.65 amperes
C. 18.75 amperes
D. 13.75 amperes
A.
Question Answer
75.
A
Reference
NEC PG. #
430.32(A)(1)
319
Nameplate rating of motor = 15 amperes x 1.15 = 17.25 amperes
O 76. Where a portable generator is used for a
portable optional standby source and is not
considered a separately derived system, the
equipment grounding conductor shall be
bonded to ________.
The generator frame and the grounded
conductor
B. The system grounding electrode
C. A grounding conductor only
D. The grounded conductor
A.
Question Answer
76.
B
Reference
NEC PG. #
702.11(B)
631
O 77. Where track lighting installed in a
continuous row, each individual section of
NOT More than ______ in length shall be
securely supported.
2 feet
B. 4 feet
C. 6 feet
D. 8 feet
A.
Question Answer
77.
B
Reference
NEC PG. #
410.154
289
O 78. A transformer is to be supplied with four
(4) parallel size 500 kcmil conductors per
phase. The conductors will enter the
enclosure on the opposite wall of the
terminals. What is the MINIMUM wirebending space required for the conductors?
10 inches
B. 12 inches
C. 14 inches
D. 16 inches
A.
Question Answer
78.
D
Reference
NEC PG. #
312.6(B)(2)
Tbl.312.6(B)
174
176
O 79. For trade size ¾ in. Type MI cable, the
radius of the inner edge of the bend shall
NOT be less than _______ times the external
diameter of the cable.
Three
B. Four
C. Five
D. Seven
A.
Question Answer
79.
C
Reference
NEC PG. #
332.24(1)
195
O 80. Manhole covers shall be OVER ______ or
otherwise require the use of tools to open.
25 lbs.
B. 50 lbs.
C. 75 lbs.
D. 100 lbs.
A.
Question Answer
80.
D
Reference
NEC PG. #
110.75(D)
45
O 81. Size 4/0 AWG, 75°C aluminum
secondary conductors of a 3-phase, deltawye transformer, shall be protected at NOT
more than _______.
175 amperes
B. 200 amperes
C. The calculated load connected to the
transformer
D. None of these, because secondary
protection is not required for multiphase,
delta-wye transformer secondary
conductors.
A.
Question Answer
81.
B
Reference
NEC PG. #
Tbl. 310.15(B)(16)
240.4(B)(3)
240.6(A)
154
90
91
Size 4/0 AWG AL conductors rated @ 75º C ampacity = 180 amperes
Next standard size OCP is rated 200 apmeres.
*NOTE – Sec. 240.4(F) requires secondary OCP on delta – wye
transformers.
O 82. For the purpose of determining
conductor fill in conduit, a flexible cord or
cable of four (4) conductors shall be treated
as ________ conductor(s).
One
B. Two
C. Three
D. Four
A.
Question
Answer
Reference
NEC PG. #
82.
A
Note 9 Chpt. 9 Tbls.
711
O 83. Where the grounding electrode system
of a building or structure consists of three
(3) driven ground rods, the ground rods shall
be spaced NOT less than ______ apart.
4 feet
B. 5 feet
C. 6 feet
D. 8 feet
A.
Question Answer
83.
C
Reference
NEC PG. #
250.53(B)
112
O 84. What is the MAXIMUM size overcurrent
protection device required to protect size 14
AWG copper conductors used for a pump
motor control-circuit that is protected by the
motor branch circuit protection device and
extends beyond the enclosure?
15 amperes
B. 20 amperes
C. 45 amperes
D. 100 amperes
A.
Question Answer
84.
C
Reference
NEC PG. #
430.72(B)(2)
Tbl. 430.72(b)
Col. C
326
327
O 85. What is the MAXIMUM number of size
12 AWG THHN conductors permitted to be
installed in a trade size 3/8 in. flexible metal
conduit (FMC) where the fittings are outside
the FMC?
Five
B. Two
C. Three
D. Four
A.
Question Answer
85.
D
Reference
NEC PG. #
Tbl. 348.22
206
3 + 1 equipment grounding conductor = 4 conductors total
O 86. A 120/240 volt, single-phase feeder of a
retail shopping mall is to supply a
noncontinuous load of 20,000 VA and a
continuous load 16,000 VA. Consider the
overcurrent device protecting the feeder
conductors is not listed for operation at 100
percent of its rating and determine the
MINIMUM size 75°C copper conductors
required for this installation
1/0 AWG
B. 2/0 AWG
C. 3/0 AWG
D. 1 AWG
A.
Question Answer
86.
B
Reference
NEC PG. #
215.2(A)(1)
59
Single – Phase current formula
Tbl. 310.15(B)(16)
154
20,000 VA x 100% = 20,000 VA
16,000 VA x 125% = 20,000 VA
Total
= 40,000 VA
I = power I = 40,000 VA = 166.6 amperes
volts
240 volts
* NOTE – Size 2/0 AWG conductors with an allowable
ampacity of 175 amperes should be selected.
O 87. Apply the optional method of
calculations for dwelling units and
determine the demand load, in kW, on the
ungrounded (line) service-entrance
conductors for the electric ranges, where a
12 unit multifamily dwelling has an 8 kW
range in each apartment.
39.36 kW
B. 30.72 kW
C. 27.00 kW
D. 96.00 kW
A.
Question Answer
87.
A
Reference
NEC PG. #
220.84(C)b.
Tbl. 220.84
69
69
8 kW x 12 units = 96 kW (connected load) x 41% = 39.36 kW
O 88. An indoor installed 100 kVA, dry-type
transformer with a 4,160 volt primary, must
have a clearance of at LEAST _______ from
combustible material unless separated from
the combustible material by a fire-resistant,
heat-insulated barrier.
6 inches
B. 8 inches
C. 10 inches
D. 12 inches
A.
Question Answer
88.
D
Reference
NEC PG. #
450.21(A)
352
O 89. Interior metal water lines located NOT
more than ____ from the point of entrance
to the building shall be permitted to be used
as a conductor to interconnect electrodes
that are part of the grounding electrode
system.
10 feet
B. 8 feet
C. 5 feet
D. 20 feet
A.
Question Answer
89.
C
Reference
NEC PG. #
250.68(C)(1)
116
O 90. The independent support wires used to
support electrical metallic tubing (EMT) and
flexible metal conduit (FMT) above a nonfire-rated ceiling shall be distinguishable
from the ceiling support wires by means of
________.
O I. Color
O II. Tagging
I only
B. II only
C. Either I or II
D. Neither I nor II
A.
Question Answer
90.
C
Reference
NEC PG. #
300.11(2)
141
O 91. Which of the following listed raceways is
approved for use supplying wet-niche
luminaires in a permanently installed
swimming pool?
Galvanized rigid metal conduit (RMC)
B. Polyvinyl chloride conduit (PVC)
C. Flexible nonmetallic conduit (FNC)
D. All of these listed are approved.
A.
Question Answer
91.
B
Reference
NEC PG. #
680.23(B)(2)
581
O 92. Power distribution blocks shall be
permitted to be placed in pull and junction
boxes having a volume over at LEAST _____
for connections of conductors installed in
boxes where the power distribution blocks
do not have uninsulated live parts exposed
within the box, whether or not the box cover
is installed.
30 cu. In.
B. 60 cu. In.
C. 75 cu. In.
D. 100 cu. In.
A.
Question Answer
92.
D
Reference
NEC PG. #
314.28(E)(2)
184
O 93. The circuit disconnecting means for non-
power-limited fire alarm (NPLFA) circuits
shall have ______ colored identification,
shall be accessible only to qualified persons
and shall be identified as “FIRE ALARM
CIRCUIT.”
Red
B. Orange
C. Yellow
D. Blue
A.
Question Answer
93.
A
Reference
NEC PG. #
760.41(B)
652
O 94. A flexible metal conduit (FMC) having a
length of 4 ft. is to supply a panelboard from
a transformer. The FMC will contain three (3)
size 400 kcmil THWN copper conductors
and one (1) size 350 kcmil THWN copper
conductor. In compliance with the NEC®,
what is the MINIMUM trade size FMC
required.
2 ½ in.
B. 3 in.
C. 3 ½ in.
D. 4 in.
A.
Question Answer
94.
C
Reference
NEC PG. #
Annex C, Tbl. C.3
755
O 95. An outside overhead span of 3-phase, 4
wire, 480Y/277 volt conductors are to be
installed between two buildings of a college
campus. The area the conductors cross will
not be subject to truck traffic. The
conductors must have a MINIMUM
clearance of ______ from final grade.
10 feet
B. 12 feet
C. 15 feet
D. 18 feet
A.
Question Answer
95.
B
Reference
NEC PG. #
225.18(2)
72
O 96. Cables over 600 volts and those rated
600 volts or less, are permitted to be
installed in a common cable tray without a
fixed barrier, where the cables over 600
volts are _______.
Type MI
B. Type NM
C. Type CT
D. Type MC
A.
Question Answer
96.
D
Reference
NEC PG. #
392.20(B)(1)
241
O 97. When calculating the total load for a
mobile home park before demand factors
are taken into consideration, each individual
mobile home lot shall be calculated at a
MINIMUM of _________.
15,000 VA
B. 16,000 VA
C. 20,000 VA
D. 24,000 VA
A.
Question Answer
97.
B
Reference
NEC PG. #
550.31(1)
489
O 98. Where a restaurant located in a retail
shopping mall has a main circuit breaker
rated for 400 amperes, the required
bonding jumper to the metal water piping
system is to be at LEAST _______ copper.
6 AWG
B. 2 AWG
C. 3 AWG
D. 4 AWG
A.
Question Answer
98.
C
Reference
NEC PG. #
250.104(A)(2)
Tbl. 250.122
119
125
O 99. In general, on the load side of the point
of grounding of a separately derived system
such as a transformer, a grounded
conductor is NOT permitted to be connected
to ________.
Equipment grounding conductors
B. Normally non-current-carrying metal parts
of equipment
C. The system bonding jumper
D. Any of these
A.
Question Answer
99.
D
Reference
NEC PG. #
250.30(A)
106
O 100. Where one or more receptacle outlets
are provided for the show window lighting in
a retail store, the outlet(s) shall be installed
within at LEAST ________ of the top of the
show window.
12 inches
B. 18 inches
C. 24 inches
D. 30 inches
A.
Question Answer
100.
B
Reference
NEC PG. #
210.62
58
Click here to advance to the
non-timed drill
O 1. After all demand factors have been taken
into consideration for an office building, the
demand load is determined to be 90,000
VA. Where the building has a 120/240 volt,
single-phase electrical system, what
MINIMUM size copper conductors with
THHW insulation are required for the
underground service-lateral conductors?
400 kcmil
B. 350 kcmil
C. 300 kcmil
D. 500 kcmil
A.
Question Answer
1.
D
Reference
NEC PG. #
Tbl. 310.15(B)(16)
Single –phase current
154
Formula
I= Power
Volts
I = 90,000VA = 375 amperes
240 volts
*Note – Size 500 kcmil THHW conductors with
an allowable ampacity of 380 amperes should
be selected.
O 2. A commercial building is to be supplied
with a transformer having a 480Y/277 volt,
3-phase primary and a 208Y/120 volt, 3phase secondary. The secondary will have a
balanced computed demand load of 416
amperes per phase. The transformer is
required to have a MINIMUM kVA rating of
_______.
100 kVA
B. 150 kVA
C. 86 kVA
D. 200 kVA
A.
Question Answer
2.
B
Reference
NEC PG. #
3 – phase power
Formula
VA = I x E x 1.732
O VA = 416 amperes x 208 volts x 1.732
O 149,866 VA ÷ 1,000 = 149.8 kVA
O 3. What is the MINIMUM size equipment
bonding jumper allowed for receptacles
connected to a 20-ampere branch circuit in
a critical care area of a hospital?
8 AWG
B. 10 AWG
C. 12 AWG
D. 14 AWG
A.
Question Answer
3.
B
Reference
NEC PG. #
517.19(C)
444
O 4. The branch circuit conductors supplying
one or more units of information technology
equipment shall have an ampacity of NOT
less than ________ of the connected load.
80 percent
B. 100 percent
C. 115 percent
D. 125 percent
A.
Question Answer
4.
D
Reference
NEC PG. #
645.5 (A)
561
O 5. In Class II, Division I hazardous locations,
an approved method of connection of
conduit boxes is __________.
Compression fittings
B. Threaded bosses
C. Welding
D. All of these
A.
Question Answer
5.
B
Reference
NEC PG. #
502.10(A)(1)(4)
386
O 6. Where a motor of more than 1 horsepower
has a temperature rise of 50°C indicated on
the nameplate, for the purpose of selecting the
overload device, this device shall be selected to
trip at NO more than ________ of the motor’s
full-load ampere rating.
(No exceptions or modifications permitted.)
100 percent
B. 115 percent
C. 125 percent
D. 130 percent
A.
Question Answer
6.
B
Reference
NEC PG. #
430.32(A)(1)
319
O 7. The MINIMUM burial depth for conduit or
cables installed under an airport runway,
concourse or tarmac is ______.
1 ½ feet
B. 2 feet
C. 3 feet
D. 1 foot
A.
Question Answer
7.
A
Reference
NEC PG. #
Tbl. 300.5
138
O 8. Liquidtight flexible metal conduit (LFMC)
is approved for use as an equipment
grounding conductor if it does NOT exceed
_______ in length.
10 feet
B. 12 feet
C. 6 feet
D. 8 feet
A.
Question Answer
8.
C
Reference
NEC PG. #
250.118(6)d.
122
O 9. Conductors supplying more than one (1)
motor shall have an ampacity of NOT less
than ______ of the full-load current rating of
the largest motor in the group and 100% of
the full-load current ratings of all the other
motors in the group.
125 percent
B. 110 percent
C. 150 percent
D. 175 percent
A.
Question Answer
9.
A
Reference
NEC PG. #
430.24(1)&(2)
318
O 10. Determine the MINIMUM size THWN
copper branch-circuit conductors permitted
to supply an ac motor when given the
following related information:
All terminations are rated for 75°C
Nameplate current rating is 25 amperes
15 minute rated motor
Short-time duty
12 AWG
B. 10 AWG
C. 8 AWG
D. 6 AWG
A.
Question Answer
10.
B
Reference
NEC PG. #
430.22(E)
Tbl. 430.22(E)
Tbl.310.15(B)(16)
316
317
154
FLC of motor = 25 amperes x 120% = 30 amperes
* NOTE – Size 10 AWG THWN copper conductors with an
allowable ampacity of the 35 amperes should be selected
O 11. When intermediate metal conduit (IMC)
is threaded in the field, a standard cutting
die with a ________ taper per ft. shall be
used.
3/8 in.
B. 1/2 in.
C. 3/4 in.
D. 1 in.
A.
Question Answer
11.
C
Reference
NEC PG. #
342.28
202
O 12. Apply no exceptions and determine the
MAXIMUM standard size nontime-delay fuse
permitted for branch-circuit, short-circuit,
and ground-fault protection for an ac motor
where given the following related
information:
2 hp – 120 volts, single-phase
Continuous-duty
Nameplate current rating – 22 amperes
No code letter
70 amperes
B. 80 amperes
A.
C. 85 amperes
D. 90 amperes
Question Answer
12.
A
Reference
NEC PG. #
430.6(A)(1)
Tbl. 430.248
240.6(A)
311
337
91
FLC of motor - 24 amperes x 300% = 72 amperes
* NOTE - In this case you must go down to the next standard
size nontime - delay fuse with an ampere rating of 70 amperes
O 13. Which of the following listed is NOT
permitted for sues as both controller and
disconnecting means for a motor?
Inverse time circuit breaker
B. Instantaneous-trip circuit breaker
C. Oil switch
D. Air-break switch
A.
Question Answer
13.
B
Reference
NEC PG. #
430.111(B)(1),(2)&(3)
332
O 14. Under which, if any, of the following
conditions is the neutral conductor to be
counted as a current-carrying conductor?
O I. When it is only carrying the unbalanced
current of a single-phase system
O II. When it is the neutral of a 3-phase wyeconnected system that consists of nonlinear
loads.
I only
B. II only
C. Neither I nor II
D. Both I and II
A.
Question Answer
14.
B
Reference
NEC PG. #
310.15(B)(5)(a)&(c)
152
O 15. Ceiling-suspended luminaires or paddle
fans located ______ or more above the
maximum water level of a spa or hot tub
shall NOT require GFCI protection.
10 feet
B. 7 ½ feet
C. 8 feet
D. 12 feet
A.
Question Answer
15.
D
Reference
NEC PG. #
680.43(B)(1)(a)
587
O 16. A junction box to be installed will contain
the following:
Three – size 6 AWG ungrounded conductors
Three – size 6 AWG grounded conductors
One – size 8 AWG equipment grounding
conductor
Three – size 12 AWG ungrounded conductors
Three – size 12 AWG grounded conductors
One – size 12 equipment grounding conductor
Four – internal clamps
O The junction box is required to have a
volume of at LEAST _______.
A.
B.
51.50 cubic inches
53.75 cubic inches
C. 46.50 cubic inches
D. 56.50 cubic inches
Question Answer
16.
A
Reference
NEC PG. #
Tbl. 314.16(B)
314.16(B)(1)&(2)
179
178
Size 6 AWG ungrounded conductors
3 x 5.00 cu. In. =
15.00 cu.in.
Size 6 AWG grounded conductors
3 x 5.00 cu. In. =
15.00 cu.in.
Size 8 AWG grounding conductors
1 x 3.00 cu.in. =
3.00 cu.in.
Size 12 AWG ungrounded conductors
3 x 2.25 cu.in. =
6.75 cu.in.
Size 12 AWG grounded conductors
3 x 2.25 cu.in. =
6.75 cu.in.
Size 12 AWG grounding conductors
Internal clamps
-0-
1 x 5.00 cu.in. =
Total =
5.00 cu.in.
51.50 cu.in.
O 17. Where conductors of size 4 AWG or
larger are installed in conduits entering a
junction box and straight pulls of the
conductors are to be made, the length of the
box shall NOT be less than _______ times
the trade of the largest raceway.
Six
B. Eight
C. Ten
D. Twelve
A.
Question Answer
17.
B
Reference
NEC PG. #
314.28(A)(1)
183
O 18. With respect to service-drop conductors
and open overhead wiring of not more than
750 volts to ground, the MINIMUM vertical
clearance that must be maintained from the
base of a swimming pool diving board and
the conductors is _________.
14 ½ feet
B. 16 ½ feet
C. 20 ½ feet
D. 22 ½ feet
A.
Question Answer
18.
D
Reference
NEC PG. #
680.8(A)
Fig. 680.8
Tbl. 680.8
577
578
578
O 19. The life safety branch of the emergency
system of a health care facility shall provide
power to ______.
O I. automatic doors used for building egress
O II. Illuminate electrical equipment
I only
B. II only
C. Both I and II
D. Neither I nor II
A.
Question Answer
19.
A
Reference
NEC PG. #
517.32(H)
448
O 20. When a building contains _______, the
building may have more than one service
without special permission being granted
from the local authority having jurisdiction.
Exit lights
B. Fire pumps
C. Computers
D. Four-hour rated fire-resistant walls
A.
Question Answer
20.
B
Reference
NEC PG. #
230.2(A)(1)
78
O 21. In general, service-drop conductors shall
have a vertical clearance of at LEAST
_______ above the roof surface of a building
having no overhang.
10 feet
B. 12 feet
C. 14 feet
D. 8 feet
A.
Question Answer
21.
D
Reference
NEC PG. #
230.24(A)
80
O 22. In general, the phase arrangement on
the three-phase busses for a three-phase
panelboard or switchboard shall be A, B, C,
as viewed from __________.
O I. Back to front
O II. Bottom to top
I only
B. II only
C. Neither I nor II
D. Both I and II
A.
Question Answer
22.
C
Reference
NEC PG. #
408.3(E)
274
O 23. Where a conductor is marked RHW-2 on
the insulation what does the -2 represent?
The cable has 2 conductors.
B. The conductor is double insulated
C. The conductor has a nylon outer jacket
D. The conductor has a maximum operating
temperature of 90°C
A.
Question Answer
23.
(D)
Reference
NEC PG. #
Tbl. 310.104(A)
168
O 24. Which of the following listed raceways is
NOT permitted for use of enclosing control
wiring for electric motor-driven fire pumps?
Flexible metal conduit (FMC)
B. Liquidtight flexible metal conduit (LFMC)
C. Liquidtight flexible nonmetallic conduit
(LFNC)
D. Intermediate metal conduit (IMC)
A.
Question Answer
24.
A
Reference
NEC PG. #
695.14(E)
620
O 25. In a hospital, low-voltage equipment that
is frequently in contact with the bodies of
persons, must operate on a voltage of _____
or less or be moisture resistant, double
insulated or approved as intrinsically safe.
10 volts
B. 24 volts
C. 50 volts
D. 120 volts
A.
Question
Answer
Reference
NEC PG. #
25.
A
517.65(A)(1),(2)&(3)
455
O 26. A grounding electrode that is the sole
connection to the made grounding
electrode, shall NOT be required to be larger
than size _____ copper conductor.
1/0 AWG
B. 6 AWG
C. 4 AWG
D. 3/0 AWG
A.
Question Answer
26.
B
Reference
NEC PG. #
250.66(A)
115
O 27. For solar photovoltaic systems, locating
the system grounded connection point as
close as practicable to the photovoltaic
source better protects the system from
_________.
Excessive voltage drop
B. Excessive resistance in the grounding
system
C. Voltage surges due to the lighting
D. Voltage surges due to ground-faults
A.
Question Answer
27.
C
Reference
NEC PG. #
690.42,IN
603
O 28, Transformers containing oil or a liquid
that will burn where located in Class I,
Division 1 locations shall be _______.
Enclosed in a fence
B. Installed in vaults only
C. Identified for Class I locations
D. Installed in a fire-resistant room
A.
Question Answer
28.
B
Reference
NEC PG. #
501.100(A)(1)
381
O 29. Where liquidtight flexible metal conduit
(LFMC) is installed in a Class I, Division 2
hazardous location, it shall be permitted to
delete the bonding jumper, where the LFMC
is NOT longer than _______ and the
overcurrent protection in the circuit is limited
to _______ or LESS and the load is not a
power utilization load.
6 feet – 20 amperes
B. 10 feet – 10 amperes
C. 6 feet – 10 amperes
D. 6 feet – 15 amperes
A.
Question Answer
29.
C
Reference
NEC PG.
#
501.30(B),Ex.(1)&2
381
O 30. Which one of the following wiring
methods is permitted to be installed in ducts
specifically fabricated for environmental air?
Rigid polyvinyl chloride conduit (PVC)
B. Electrical metallic tubing (EMT)
C. Armored Cable (AC)
D. Nonmetallic sheathed cable (NM)
A.
Question Answer
30.
B
Reference
NEC PG. #
300.22(B)
144
O 31. An adjustable overload protection device
protecting a single phase, 240-volt,
continuous-duty, 5 hp, ac motor with a FLA
rating of 26 amperes and a temperature rise
of 50°C marked on the nameplate, shall be
selected to trip at NOT more than ______.
(Consider the value you select will enable
the motor to start without tripping and
modification of this value is not necessary)
29.9 amperes
B. 32.2 amperes
C. 33.8 amperes
D. 36.4 amperes
A.
Question Answer
31.
A
Reference
NEC PG. #
430.6(A)(2)
Tbl.430.248
430.32(A)(1)
312
337
319
FLA of motor = 26 amperes x 115% = 29.9 amperes
O 32. In Class II, Division 1 locations, where
pendant mounted luminaires are suspended
by rigid metal conduit (RMC) and a means
for flexibility is not provided, the RMC shall
have a length of NOT more than ________.
12 inches
B. 18 inches
C. 24 inches
D. 30 inches
A.
Question Answer
32.
A
Reference
NEC PG. #
502.130(B)(4)
390
O 33. A commercial kitchen is to have the
following cooking related equipment
installed:
One – 14 kW range
One – 5.0 kW water heater
One – 0.75 kW mixer
One – 2.5 kW dishwasher
One – 2.0 kW booster heater
One – 2.0 kW broiler
O Determine the demand load, in kW, after
applying the demand factors for the kitchen
equipment.
19.00 kW
B. 26.25 kW
A.
C. 18.38 kW
D. 17.06 kW
Question Answer
33.
A
Reference
NEC PG. #
220.56
Tbl.220.56
65
67
14.00 kw – range
5.00 kw - water heater
0.75 kw – mixer
2.50 kw – dishwasher
2.00 kw – booster heater
2.00 kw – broiler
26.25 kw – total connected load x 65% = 17.06
•
•
NOTE – However the NEC ® states the demand shall
not be less than the two largest pieces of equipment.
14.00 kw + 5.00 kw = 19 kw demand
O 34. In a minor repair commercial garage,
any unventilated pit or below-grade work
area is classified as a _______ hazardous
location, where gaseous liquids and fuels
are not transferred.
Class I, Division 2
B. Class II, Division 1
C. Class II, Division 2
D. Class I, Division 1
A.
Question Answer
34.
A
Reference
NEC PG. #
511.3(D)(3)(b)
421
O 35. Where a motor controller enclosure is
located outdoors and is subject to be
exposed to sleet, it shall have a MINIMUM
rating of _______, where the controller
mechanism is required to be operable when
ice covered.
Type 3
B. Type 3S
C. Type 3R
D. Type 3SX
A.
Question Answer
35.
B
Reference
NEC PG. #
Tbl. 110.28
41
O 36. When buried raceways pass under a
commercial driveway or parking lot the
MINIMUM cover requirements ______.
Decrease if installed in rigid metal conduit
(RMC)
B. Do not change in regard to wiring methods
used
C. Shall be increased for direct-buried cables
D. Shall be increased, decreased or remain
the same, depending on the wiring method
used
A.
Question Answer
36.
B
Reference
NEC PG. #
Tbl. 300.5
138
O 37. The National Electrical Code® requires
ventilation of a battery room where batteries
are being charged to prevent ___________.
Battery corrosion
B. Electrostatic charge
C. Deterioration of the building steel
D. An accumulation of an explosive mixture
A.
Question Answer
37.
D
Reference
NEC PG. #
480.9(A)
360
O 38. For other than Design B energy-efficient
motors, where the setting specified in Table
430.52 of the NEC® is not sufficient for the
starting current of the motor, the setting of
an instantaneous trip circuit breaker shall
be permitted to be increase3d, but in NO
case exceed ________ of the full-load
current of the motor.
1300 percent
B. 1700 percent
C. 1100 percent
D. 800 percent
A.
Question Answer
38.
A
Reference
NEC PG. #
430.52(C)(3), Ex.1
323
O 39. Where given the following related
information, determine the MAXIMUM standard
size overcurrent protection required for the
primary and secondary side of a transformer,
when primary and secondary overcurrent
protection is to be provided.
150 kVA rating
Primary – 480 volt, 3-phase, 3-wire
Secondary – 208Y/120 volt, 3-phase, 4-
wire
A.
B.
C.
D.
Primary – 500 amperes, Secondary – 500
amperes
Primary – 450 amperes, Secondary – 600
amperes
Primary – 500 amperes, Secondary – 450
amperes
Primary – 450 amperes, Secondary – 500
amperes
Question Answer
39.
B
Reference
NEC PG. #
3 – Phase Current
Formula
450.3(B)
Tbl. 450.3(B)
240.6(A)
348
349
91
(Primary)
I=
VA___ I = __150,000__ = 150,000 = 180 amps x 250% = 450 amps
E x 1.732
480 x 1.732
831.36
(Secondary )
I=
VA___ I = __150,000__ = 150,000 = 416 amps x 250% = 520 amps
E x 1.732
208 x 1.732
36.25
O 40. For capacitors of over 600 volts, a
means shall be provided to reduce the
residual voltage of a capacitor to ________
after the capacitor is disconnected from the
source of supply.
50 volts or less within 1 minute
B. 24 volts or less within 1 minute
C. 50 volts or less within 10 minutes
D. 50 volts or less within 5 minutes
A.
Question Answer
40.
D
Reference
NEC PG. #
460.28(A)
358
O 41. Apply no exceptions and determine the
MAXIMUM standard size time-delay fuses
permitted to be used for branch-circuit,
short-circuit, and ground-fault protection for
a 15 hp, 480-volt, three-phase, continuousduty, wound rotor motor.
35 amperes
B. 40 amperes
C. 50 amperes
D. 55 amperes
A.
Question Answer
41.
A
Reference
NEC PG. #
430.6(A)(1)
Tbl. 430.250
Tbl. 430.52
240.6(A)
311
338
323
91
FLC of motor = 21 amperes x 175% = 36.75 amperes
* NOTE – In this situation you are required to go DOWN to
the next standard size fuses with a rating of 35 amperes
O 42. In general, when conductors of different
insulation rating are installed in a common
raceway and the voltage is 600 colts or less,
the NEC® requires __________.
All conductors shall have an insulation
rating equal to at least the maximum circuit
voltage applied to any conductor on the
raceway
B. The conduit allowable fill to be limited to 31
percent
C. All conductors within the raceway shall have
a temperature rating of 75°C
D. The insulation of the lower rated conductors
to be identified with blue or yellow colors.
A.
Question Answer
42.
A
Reference
NEC PG. #
300.3(C)(1)
136
O 43. Where used outdoors, aluminum
grounding conductors shall NOT be
terminated within _____ of the earth.
18 inches
B. 24 inches
C. 3 feet
D. 6 feet
A.
Question Answer
43.
A
Reference
NEC PG. #
250.64(A)
113
O 44. A 6,000 sq. ft. bank building is to be
constructed and the number of generalpurpose receptacles to be installed in the
building is yet to be determined; the building
will also have an electric sign. Determine the
MINIMUM number of 120-volt, 20-ampere
branch circuits required for the lighting,
receptacles and the sign.
12
B. 13
C. 14
D. 15
A.
Question Answer
44.
D
Reference
NEC PG. #
Art. 100
210.19(A)(1)
Tbl. 220.12
600.5(A)
27
52
63
519
6000 sq. ft. x 3.5 VA = 21,000 VA x 125% = 26,250 VA (lighting )
6000 sq. ft. x 1.0 VA =
6,000 VA (receptacles)
32,250 VA ( recpts. & ltg.)
120 volts x 20 amperes = 2,400 VA of one circuit
32,250 VA (load)/2,400 VA (one circuit) = 13.4 ckts. = 14 circuits
14 circuits ( lighting & receptacles) + 1 sign circuit = 15 circuits total
O 45. Enclosures containing circuit breakers,
switches and motor controllers located in
Class II, Division 2 locations, shall be ______
or otherwise identified for the location.
Gastight
B. Vapor-proof
C. Dust tight
D. Stainless steel
A.
Question Answer
45.
C
Reference
NEC PG. #
502.115(B)
388
O 46. Where installed for a commercial
occupancy, determine the MINIMUM size
THWN copper conductors required from the
terminals of a 3-phase, 480Y/277 volt, 4wire, 200 kW generator to the first
distribution device(s) containing overcurrent
protection, where the design and operation
of the generator does NOT prevent
overloading.
250 kcmil
B. 300 kcmil
C. 400 kcmil
D. 500 kcmil
A.
Question Answer
46.
B
Reference
NEC PG. #
3 – Phase current
Formula
455.13
Tbl. 310.15(B)(16)
347
154
I = kW x 1,000
I = 200 x 1,000 = 200,00 = 240.56 amperes (FLC)
volts x 1.732
480 x 1.732
831.36
241 amperes x 115% = 277 amperes (required ampacity of conductors)
*NOTE – Size 300 kcmil THWN conductors with an allowable
ampacity of 285 amperes should be selected.
O 47. Where required, conduit seals installed
in Class I Divisions 1 & 2 locations shall
have the minimum thickness of the sealing
compound not less than the trade size of
the sealing fitting and, in NO case less than
_______ thick.
1/2 in.
B. 5/8 in.
C. 3/4 in.
D. 1 in.
A.
Question Answer
47.
B
Reference
NEC PG. #
501.15(C)(3)
379
O 48. A dwelling unit to be built will have
1,400 sq. ft. of livable space on the main
floor, a 1,400 sq. ft. basement (unfinished
but adaptable for future use), a 200 sq. ft.
open porch and a 600 sq. ft. garage.
Determine the MINIMUM number of 15ampere, 120-volt general lighting branchcircuits required for the dwelling.
Four
B. Five
C. Six
D. Seven
A.
Question Answer
48.
B
Reference
NEC PG. #
220.12
Tbl. 220.12
61
63
1,400 sq. ft. + 1,400 sq. ft. = 2,880sq. Ft. x VA = 8,400 VA
120 volts x 15 amperes = 1,800 VA of one circuit
8,400 VA (load)
4.6 = 5 circuits total
1,800 VA ( one circuit)
O 49. The optional method of feeder and
service load calculations for dwelling units is
reserved for feeder and service conductors
with a MINIMUM ampacity of ________ or
greater.
400 amperes
B. 200 amperes
C. 150 amperes
D. 100 amperes
A.
Question Answer
49.
D
Reference
NEC PG. #
220.82(A)
67
O 50. In an industrial establishment, what is
the MAXIMUM length of 200 ampere rated
busway that may be tapped to a 600
ampere rated busway, without additional
overcurrent protection?
10 feet
B. 25 feet
C. 50 feet
D. 75 feet
A.
Question Answer
50.
C
Reference
NEC PG. #
368.17(B),Ex.
225
O 51. Thermal insulation is not permitted to be
installed above a recessed luminaire or
WITHIN _____ of the recessed luminaire’s
enclosure, wiring compartment, ballast,
transformer, LED driver or power supply,
unless the luminaire is identified as Type IC
for insulation contact.
3 inches
B. 4 inches
C. 6 inches
D. 8 inches
A.
Question Answer
51.
A
Reference
NEC PG. #
410.116(B)
286
O 52. What is the MINIMUM height allowed for
a fence enclosing an outdoor installation of
2,400 volt electrical equipment?
6 feet
B. 7 feet
C. 8 feet
D. 9 feet
A.
Question Answer
52.
B
Reference
NEC PG. #
110.31
40
O 53. All exposed non-current-carrying metal
parts of an information technology system
shall ______ or shall be double insulated.
Be bonded to the equipment grounding
conductor
B. Not be bonded to the equipment grounding
conductor
C. Be bonded to the grounded conductor
D. Be isolated
A.
Question Answer
53.
A
Reference
NEC PG. #
645.15
562
O 54. Storage batteries used as a source of
power for emergency systems shall be of a
suitable rating and capacity to supply and
maintain the total load for at
LEAST________.
1/2 hour
B. 1 hour
C. 1 ½ hour
D. 2 hours
A.
Question Answer
54.
C
Reference
NEC PG. #
700.12(A)
624
O 55. Circuit breakers rated at _____ or less
and 600 volts or less shall have the ampere
rating molded, stamped, etched or similarly
marked into their handles or escutcheon
areas.
600 amperes
B. 200 amperes
C. 400 amperes
D. 100 amperes
A.
Question Answer
55.
D
Reference
NEC PG. #
240.83(B)
96
O 56. What percent of electrical supplied
spaces in a recreational vehicle park must
be equipped with at least one (1) 30-ampere
125-volt receptacle outlet?
75 percent
B. 60 percent
C. 70 percent
D. 100 percent
A.
Question Answer
56.
C
Reference
NEC PG. #
551.71
500
O 57. A straight pull of size 250 kcmil and 350
kcmil conductors is to be made in a junction
box that will have one (1) 3 in. conduit and
two (2) 2 ½ in. conduits entering on the
same side and exiting on the opposite wall.
No splices or terminations will be made in
the box. Which of the following listed
junction boxes is the MINIMUM required for
this installation?
18 in. x 12 in.
B. 20 in. x 18 in.
C. 20 in. x 20 in.
D. 24 in. x 24 in.
A.
Question Answer
57.
D
Reference
NEC PG. #
314.28(A)(1)
183
3 in. (largest conduit) x 8 = 24 in.
O 58. Where conduits enter a floor-standing
switchboard or panelboard at the bottom,
the conduits, including their end fittings,
shall NOT rise more than _______ above the
bottom of the enclosure.
6 inches
B. 3 inches
C. 2 inches
D. 4 inches
A.
Question Answer
58.
B
Reference
NEC PG. #
408.5
275
O 59. A bonding jumper connected between
the communications grounding electrode
and power grounding electrode system at
the building or structure service where
separate electrodes are used shall NOT be
smaller than ______ copper.
8 AWG
B. 6 AWG
C. 12 AWG
D. 10 AWG
A.
Question Answer
59.
B
Reference
NEC PG. #
800.100(D)
674
O 60. Which of the following listed copper
conductors, is the MINIMUM size 75°C
rated conductors required to supply a
continuous-duty, 25 hp, 208-volt, 3-phase
motor, where the motor is on the end of a
short conduit run that contains only three
(3) conductors, at an ambient temperature
of 115°F?
1 AWG THWN
B. 2 AWG THWN
C. 1 AWG THHN
D. 1/0 AWG THWN
A.
Question
Answer
Reference
NEC PG. #
60.
A
430.22
Tbl. 430.250
Tbl. 310.15(B)(16)(a)
Tbl. 310.15(B)(16)
316
338
150
154
25 hp motor FLC = 74.8 amperes x 125% = 93.5 amperes
93.5 amperes ÷ .75 (temperature correction) = 124.6 amperes
* NOTE – The wire size needs to be increased because of the
elevated ambient temperature. Size 1 AWG THWN conductors with
allowable ampacity of 130 amperes should be selected
O 61. Single-conductor cable Type ______
shall be permitted in exposed outdoor
locations in photovoltaic source circuits for
photovoltaic module interconnections within
the photovoltaic array.
UF
B. THHN
C. USE-2
D. THWN
A.
Question Answer
61.
C
Reference
NEC PG. #
690.31(B)
601
O 62. For track lighting installed in a retail
store, a MAXIMUM of two (2) feet of lighting
track or fraction thereof shall be considered
______.
150 VA
B. 180 VA
C. 200 VA
D. 100 VA
A.
Question Answer
62.
A
Reference
NEC PG. #
220.43(B)
64
O 63. Where fixed wiring above bulk fuel
storage tanks is installed in PVC conduit, the
PVC shall be Schedule ________.
20
B. 40
C. 80
D. 100
A.
Question Answer
63.
C
Reference
NEC PG. #
515.7(A)
429
O 64. Disregarding exceptions, the MINIMUM
size grounded or undergrounded conductors
permitted to be connected in parallel is
_____.
6 AWG
B. 1 AWG
C. 2 AWG
D. 1/0 AWG
A.
Question Answer
64.
D
Reference
NEC PG. #
310.10(H)(1)
429
O 65. In general, 4 in. wide underfloor
raceways shall have a covering of wood or
concrete of NOT less than _______ above
the raceway.
½ in.
B. ¾ in.
C. 1 in.
D. 1 ¼ in.
A.
Question Answer
65.
B
Reference
NEC PG. #
390.4(A)
238
O 66. Exposed trade size ¾ in. Schedule 40
PVC conduit is required to be securely
supported at intervals NOT to exceed
_______.
3 feet
B. 4 feet
C. 6 feet
D. 8 feet
A.
Question Answer
66.
A
Reference
NEC PG. #
352.30(B)
Tbl. 352.30
209
210
O 67. Receptacles located within the patient
care areas of pediatric wards shall be
______ or shall employ a listed tamperresistant cover.
15 ampere rated
B. Provided with GFCI
C. A single receptacle type
D. Listed tamper-resistant
A.
Question Answer
67.
D
Reference
NEC PG. #
517.18(C)
444
O 68. What is the MAXIMUM length permitted
of a flexible cord that may be used to cordand-plug connect a water circulating pump
motor for a swimming pool at a dwelling?
3 feet
B. 4 feet
C. 6 feet
D. 10 feet
A.
Question Answer
68.
A
Reference
NEC PG. #
680.21(A)(5)
579
O 69. The MAXIMUM height above the floor or
working platform to the center of the
operating handle of a service disconnecting
switch when it is in the ON position must not
exceed ______.
6 feet
B. 6 ft. 6 in.
C. 6 ft. 7 in.
D. 7 feet
A.
Question Answer
69.
C
Reference
NEC PG. #
404.8(A)
267 & 268
O 70. The upward discharging vent of an
underground fuel tank of motor fuel
dispensing facilities is classified as a Class I,
Division 1 location WITHIN ______ of the
open vent.
3 feet
B. 5 feet
C. 6 feet
D. 8 feet
A.
Question Answer
70.
B
Reference
NEC PG. #
Tbl. 514.3(B)(1)
427
O 71. Flexible metallic tubing (FMT) shall NOT
be used in lengths exceeding _______.
5 feet
B. 6 feet
C. 8 feet
D. 10 feet
A.
Question Answer
71.
B
Reference
NEC PG. #
360.12(6)
219
O 72. Unless approved for a higher voltage,
surface nonmetallic raceways are NOT
approved where the voltage is ______ or
more between conductors.
120 volts
B. 150 volts
C. 300 volts
D. 250 volts
A.
Question Answer
72.
C
Reference
NEC PG. #
388.12(3)
237
O 73. What is the MINIMUM permitted sill
height of a transformer vault doorway?
2 inches
B. 8 inches
C. 6 inches
D. 4 inches
A.
Question Answer
73.
D
Reference
NEC PG. #
450.43(B)
354
O 74. PVC conduit used exposed in areas of
physical damage shall be ________.
Type Schedule 80
B. Type Schedule 40
C. Type Schedule 100
D. Prohibited
A.
Question Answer
74.
A
Reference
NEC PG. #
352.10(F),IN
209
O 75. Determine the MAXIMUM setting
permitted for the overload protection for a 7
½ hp, 3-phase, 480 volt, induction-type ac
motor with a full-load current of 15
amperes, an 86% power factor, and a
service factor of 1.00 indicated on the
nameplate. (Assume exceptions and
modifications are not to be applied.)
17.25 amperes
B. 12.65 amperes
C. 18.75 amperes
D. 13.75 amperes
A.
Question Answer
75.
A
Reference
NEC PG. #
430.32(A)(1)
319
Nameplate rating of motor = 15 amperes x 1.15 = 17.25 amperes
O 76. Where a portable generator is used for a
portable optional standby source and is not
considered a separately derived system, the
equipment grounding conductor shall be
bonded to ________.
The generator frame and the grounded
conductor
B. The system grounding electrode
C. A grounding conductor only
D. The grounded conductor
A.
Question Answer
76.
B
Reference
NEC PG. #
702.11(B)
631
O 77. Where track lighting installed in a
continuous row, each individual section of
NOT More than ______ in length shall be
securely supported.
2 feet
B. 4 feet
C. 6 feet
D. 8 feet
A.
Question Answer
77.
B
Reference
NEC PG. #
410.154
289
O 78. A transformer is to be supplied with four
(4) parallel size 500 kcmil conductors per
phase. The conductors will enter the
enclosure on the opposite wall of the
terminals. What is the MINIMUM wirebending space required for the conductors?
10 inches
B. 12 inches
C. 14 inches
D. 16 inches
A.
Question Answer
78.
D
Reference
NEC PG. #
312.6(B)(2)
Tbl.312.6(B)
174
176
O 79. For trade size ¾ in. Type MI cable, the
radius of the inner edge of the bend shall
NOT be less than _______ times the external
diameter of the cable.
Three
B. Four
C. Five
D. Seven
A.
Question Answer
79.
C
Reference
NEC PG. #
332.24(1)
195
O 80. Manhole covers shall be OVER ______ or
otherwise require the use of tools to open.
25 lbs.
B. 50 lbs.
C. 75 lbs.
D. 100 lbs.
A.
Question Answer
80.
D
Reference
NEC PG. #
110.75(D)
45
O 81. Size 4/0 AWG, 75°C aluminum
secondary conductors of a 3-phase, deltawye transformer, shall be protected at NOT
more than _______.
175 amperes
B. 200 amperes
C. The calculated load connected to the
transformer
D. None of these, because secondary
protection is not required for multiphase,
delta-wye transformer secondary
conductors.
A.
Question Answer
81.
B
Reference
NEC PG. #
Tbl. 310.15(B)(16)
240.4(B)(3)
240.6(A)
154
90
91
Size 4/0 AWG AL conductors rated @ 75º C ampacity = 180 amperes
Next standard size OCP is rated 200 apmeres.
*NOTE – Sec. 240.4(F) requires secondary OCP on delta – wye
transformers.
O 82. For the purpose of determining
conductor fill in conduit, a flexible cord or
cable of four (4) conductors shall be treated
as ________ conductor(s).
One
B. Two
C. Three
D. Four
A.
Question
Answer
Reference
NEC PG. #
82.
A
Note 9 Chpt. 9 Tbls.
711
O 83. Where the grounding electrode system
of a building or structure consists of three
(3) driven ground rods, the ground rods shall
be spaced NOT less than ______ apart.
4 feet
B. 5 feet
C. 6 feet
D. 8 feet
A.
Question Answer
83.
C
Reference
NEC PG. #
250.53(B)
112
O 84. What is the MAXIMUM size overcurrent
protection device required to protect size 14
AWG copper conductors used for a pump
motor control-circuit that is protected by the
motor branch circuit protection device and
extends beyond the enclosure?
15 amperes
B. 20 amperes
C. 45 amperes
D. 100 amperes
A.
Question Answer
84.
C
Reference
NEC PG. #
430.72(B)(2)
Tbl. 430.72(b)
Col. C
326
327
O 85. What is the MAXIMUM number of size
12 AWG THHN conductors permitted to be
installed in a trade size 3/8 in. flexible metal
conduit (FMC) where the fittings are outside
the FMC?
Five
B. Two
C. Three
D. Four
A.
Question Answer
85.
D
Reference
NEC PG. #
Tbl. 348.22
206
3 + 1 equipment grounding conductor = 4 conductors total
O 86. A 120/240 volt, single-phase feeder of a
retail shopping mall is to supply a
noncontinuous load of 20,000 VA and a
continuous load 16,000 VA. Consider the
overcurrent device protecting the feeder
conductors is not listed for operation at 100
percent of its rating and determine the
MINIMUM size 75°C copper conductors
required for this installation
1/0 AWG
B. 2/0 AWG
C. 3/0 AWG
D. 1 AWG
A.
Question Answer
86.
B
Reference
NEC PG. #
215.2(A)(1)
59
Single – Phase current formula
Tbl. 310.15(B)(16)
154
20,000 VA x 100% = 20,000 VA
16,000 VA x 125% = 20,000 VA
Total
= 40,000 VA
I = power I = 40,000 VA = 166.6 amperes
volts
240 volts
* NOTE – Size 2/0 AWG conductors with an allowable
ampacity of 175 amperes should be selected.
O 87. Apply the optional method of
calculations for dwelling units and
determine the demand load, in kW, on the
ungrounded (line) service-entrance
conductors for the electric ranges, where a
12 unit multifamily dwelling has an 8 kW
range in each apartment.
39.36 kW
B. 30.72 kW
C. 27.00 kW
D. 96.00 kW
A.
Question Answer
87.
A
Reference
NEC PG. #
220.84(C)b.
Tbl. 220.84
69
69
8 kW x 12 units = 96 kW (connected load) x 41% = 39.36 kW
O 88. An indoor installed 100 kVA, dry-type
transformer with a 4,160 volt primary, must
have a clearance of at LEAST _______ from
combustible material unless separated from
the combustible material by a fire-resistant,
heat-insulated barrier.
6 inches
B. 8 inches
C. 10 inches
D. 12 inches
A.
Question Answer
88.
D
Reference
NEC PG. #
450.21(A)
352
O 89. Interior metal water lines located NOT
more than ____ from the point of entrance
to the building shall be permitted to be used
as a conductor to interconnect electrodes
that are part of the grounding electrode
system.
10 feet
B. 8 feet
C. 5 feet
D. 20 feet
A.
Question Answer
89.
C
Reference
NEC PG. #
250.68(C)(1)
116
O 90. The independent support wires used to
support electrical metallic tubing (EMT) and
flexible metal conduit (FMT) above a nonfire-rated ceiling shall be distinguishable
from the ceiling support wires by means of
________.
O I. Color
O II. Tagging
I only
B. II only
C. Either I or II
D. Neither I nor II
A.
Question Answer
90.
C
Reference
NEC PG. #
300.11(2)
141
O 91. Which of the following listed raceways is
approved for use supplying wet-niche
luminaires in a permanently installed
swimming pool?
Galvanized rigid metal conduit (RMC)
B. Polyvinyl chloride conduit (PVC)
C. Flexible nonmetallic conduit (FNC)
D. All of these listed are approved.
A.
Question Answer
91.
B
Reference
NEC PG. #
680.23(B)(2)
581
O 92. Power distribution blocks shall be
permitted to be placed in pull and junction
boxes having a volume over at LEAST _____
for connections of conductors installed in
boxes where the power distribution blocks
do not have uninsulated live parts exposed
within the box, whether or not the box cover
is installed.
30 cu. In.
B. 60 cu. In.
C. 75 cu. In.
D. 100 cu. In.
A.
Question Answer
92.
D
Reference
NEC PG. #
314.28(E)(2)
184
O 93. The circuit disconnecting means for non-
power-limited fire alarm (NPLFA) circuits
shall have ______ colored identification,
shall be accessible only to qualified persons
and shall be identified as “FIRE ALARM
CIRCUIT.”
Red
B. Orange
C. Yellow
D. Blue
A.
Question Answer
93.
A
Reference
NEC PG. #
760.41(B)
652
O 94. A flexible metal conduit (FMC) having a
length of 4 ft. is to supply a panelboard from
a transformer. The FMC will contain three (3)
size 400 kcmil THWN copper conductors
and one (1) size 350 kcmil THWN copper
conductor. In compliance with the NEC®,
what is the MINIMUM trade size FMC
required.
2 ½ in.
B. 3 in.
C. 3 ½ in.
D. 4 in.
A.
Question Answer
94.
C
Reference
NEC PG. #
Annex C, Tbl. C.3
755
O 95. An outside overhead span of 3-phase, 4
wire, 480Y/277 volt conductors are to be
installed between two buildings of a college
campus. The area the conductors cross will
not be subject to truck traffic. The
conductors must have a MINIMUM
clearance of ______ from final grade.
10 feet
B. 12 feet
C. 15 feet
D. 18 feet
A.
Question Answer
95.
B
Reference
NEC PG. #
225.18(2)
72
O 96. Cables over 600 volts and those rated
600 volts or less, are permitted to be
installed in a common cable tray without a
fixed barrier, where the cables over 600
volts are _______.
Type MI
B. Type NM
C. Type CT
D. Type MC
A.
Question Answer
96.
D
Reference
NEC PG. #
392.20(B)(1)
241
O 97. When calculating the total load for a
mobile home park before demand factors
are taken into consideration, each individual
mobile home lot shall be calculated at a
MINIMUM of _________.
15,000 VA
B. 16,000 VA
C. 20,000 VA
D. 24,000 VA
A.
Question Answer
97.
B
Reference
NEC PG. #
550.31(1)
489
O 98. Where a restaurant located in a retail
shopping mall has a main circuit breaker
rated for 400 amperes, the required
bonding jumper to the metal water piping
system is to be at LEAST _______ copper.
6 AWG
B. 2 AWG
C. 3 AWG
D. 4 AWG
A.
Question Answer
98.
C
Reference
NEC PG. #
250.104(A)(2)
Tbl. 250.122
119
125
O 99. In general, on the load side of the point
of grounding of a separately derived system
such as a transformer, a grounded
conductor is NOT permitted to be connected
to ________.
Equipment grounding conductors
B. Normally non-current-carrying metal parts
of equipment
C. The system bonding jumper
D. Any of these
A.
Question Answer
99.
D
Reference
NEC PG. #
250.30(A)
106
O 100. Where one or more receptacle outlets
are provided for the show window lighting in
a retail store, the outlet(s) shall be installed
within at LEAST ________ of the top of the
show window.
12 inches
B. 18 inches
C. 24 inches
D. 30 inches
A.
Question Answer
100.
B
Reference
NEC PG. #
210.62
58