1
Q
T/F: The grounded conductor and the grounding conductor are one and the same conductor and perform the same function.
A
False
2
Q
Why are all the noncurrent-carrying metal parts bonded together in a wiring system?
A) to make the system sturdy
B) to stabilize the voltage
C) to provide a low-resistance path to ground
A
C) to provide a low-resistance path to ground
3
Q
In a three-phase system, if Phase A conductor contacts Phase B conductor, is it a short circuit or a ground fault?
A
Short circuit
4
Q
If a circuit breaker ahead of a fault trips at 100 amperes of current, what is the maximum value of fault current that may flow through a fault?
A) Cannot determine from this info
B) unlimited
C) 100A
A
100A
5
Q
If a hot conductor contacts the metal enclosure of a panel, is this considered a ground fault or a short circuit?
A
ground fault
6
Q
What do we have if the neutral conductor contacts a metal receptacle box? ground fault or short circuit
A
ground fault
7
Q
T/F
System grounding connects the metal parts of the system, like the boxes and motor frame, to the electrical system’s neutral conductor.
A
False
8
Q
Which one of the following systems does not have to be grounded?
A) 24V control circuit
B) 120V household circuit
C) 480V motor power
A
A) 24V control circuit
9
Q
To be effective, grounding systems must _____.
A.
step down the voltage on the primary
B.
protect the system from lightning
C.
monitor the current
A
B. protect the system from lightning
10
Q
Which of the following cannot be used as a grounding electrode?
A. Conductive water pipe B. Ring made of wire C. 10' black iron gas pipe
A
C. 10’ black iron gas pipe
11
Q
Where would you find the requirements for sizing a grounding electrode conductor?
A. NEC Article 505 B. NEC Section 250.50 C. NEC Table 250.66
A
C. NEC Table 250.66
12
Q
Which of the following materials cannot be used as a grounding electrode conductor?
A. Stranded galvanized steel B. Stranded aluminum C. Solid copper D. Stranded copper-clad aluminum
A
A. stranded galvanized steel
13
Q
T/F: A metal underground tank or metal well casing can be used as a grounding electrode.
A
True
14
Q
Equipment grounding connects to which of the following?
A. Enclosures B. Current-carrying conductors C. Neutral conductor
A
Enclosures
15
Q
What is the EGC designed to carry? Question content area bottom Part 1 A. Line voltage B. Unbalanced current C. Fault current
A
c. fault current
16
Q
What factor determines the size of the EGC? Question content area bottom Part 1 A. Number of duplex outlets in the circuit B. Size of the fuse in the circuit C. Ambient temperature D. Size of the "hot" conductor
A
size of the overcurrent protection
17
Q
Which one of the following methods should not be used to ground a metal residential receptacle box?
Question content area bottom
Part 1
A.
A grounding screw secured to the box and designed for this purpose
B.
A grounding clip attached to the box
C.
Wrapping the bare ground around the screw that holds the receptacle
A
C
18
Q
If multiple conduits enter an enclosure and the rules say that these conduits must be bonded, must you install a separate bonding jumper from each of them to the grounding terminals at the enclosure? Question content area bottom Part 1 A. No B. Yes, if more than three conduits C. Yes
A
No
19
Q
The maximum length of the conductor allowed when running a bonding conductor outside a raceway is \_\_\_\_\_. Question content area bottom Part 1 A. 5 feet B. 10 feet C. 6 feet D. not specified in the NECSuperscript ®
A
6’
20
Q
The purpose of an effective grounding path is to conduct any \_\_\_\_\_ that might occur in the system. Question content area bottom Part 1 A. fault current B. overcurrent C. unbalanced current
A
fault current
21
Q
Which of the following circuits must be grounded? Question content area bottom Part 1 A. Secondary circuits in lighting systems B. Circuits for electrolytic cells C. Circuits for cranes that operate over combustible fibers. D. Separately derived systems
A
D. separately derived systems
22
Q
Where must the EGC originate in a separately derived system that originates in a transformer? Question content area bottom Part 1 A. At the primary B. At the power company C. At the secondary
A
A. at the primary
23
Q
When running power from one building to another, must you always run both the EGC and the grounded conductor to the second building? Question content area bottom Part 1 A. Only in certain conditions B. Never C. Yes
A
only in certain conditions
24
Q
how long do rebars have to be to be used as ground
A
20’ long, and encased in concrete, and some other conditions
25
the metal frame of a building can be used as ground when buried at least how many ft
10'
26
Rod, pipe, and plate electrodes must have a resistance to ground of less than X ohms
25 ohms or less
27
A ground ring shall not use less than X gauge copper
2AWG
28
Grounding clamp connection must be made within how many feet from the point where the pipe enters the building
within 5' of the pipe entering the building
29
grounding electrodes (ground rods) to be spaced at least X ft apart
at least 6' apart
30
what materials can ground rods be made of...
stainless steel, iron, steel, copper plated
NOT aluminum
31
What table is used to size the grounding electrode conductor?
NEC Table 250.66
32
What table is used to determine the size of the service-entrance conductor? (determined from ampacity)
NEC Table 310.16
33
Table 310.16 shows that the service conductor size (copper wire at 75 degrees C) for a 150A service is 1/0 AWG. Which of the three AWG copper electrode conductor sizes below would be used with this service?
No 4
No 6
No 8
??
34
Which table is: Minimum Size Equipment Grounding Conductors for Grounding Raceway and Equipment
NEC Table 250.122
35
Assuming 75 degree copper conductors, a 200A commercial service would require what size service conductor
1/0
2/0
3/0
4/0
3/0
36
Which of the following items is not a component of the resistance of a grounding system?
Question content area bottom
Part 1
A.
Resistance of the earth around the electrode
B.
Resistance of the conductor connecting the ground electrode
C.
Impedance of any transformers in the system
D.
Resistance between the ground electrode and the soil
C
37
```
Can a three-point resistance test be performed when only one electrode is installed?
Question content area bottom
Part 1
A.
Yes, if the electrode is moved to three separate locations
B.
Yes
C.
No
```
NO
38
```
What is the LEAST height above areas accessible to vehicles that electric signs should be when NOT protected from physical damage?
Question content area bottom
Part 1
A.
16 feet
B.
18 feet
C.
14 feet
D.
12 feet
```
C. 14'
39
```
What is the LEAST amount of free conductor, measured from the point in the box where it emerges from its raceway, that shall be left at each junction box or outlet box for splices or connection to devices?
Question content area bottom
Part 1
A.
6 inches
B.
8 inches
C.
12 inches
D.
4 inches
```
6"
40
```
Unless the luminaire is identified as Type IC for insulation contact, thermal insulation should not be installed above a recessed luminaire or within how many inches of the recessed luminaire's enclosure?
Question content area bottom
Part 1
A.
3 inches
B.
2 inches
C.
1 inches
D.
1/2 inch
```
3"
41
```
When connecting to luminaires, trade size 3/8 in. flexible metal conduit (FMC) is permitted to enclose tap conductors, provided the length of the FMC does NOT exceed _____.
Question content area bottom
Part 1
A.
4 feet
B.
3 feet
C.
8 feet
D.
6 feet
```
D. 6'
42
```
Where a lighting track is installed with two (2), four (4) ft. sections, mounted end-to-end, how many supports are required?
Question content area bottom
Part 1
A.
four
B.
two
C.
five
D.
three
```
D. 3
43
The EGC for a flexible metal conduit connection to a motor supplied with a 20A circuit is
A. 8 AWG copper
B. 10 AWG copper
C. 12 AWG copper
D. 14 AWG copper
check 250.122
| c. 12AWG
44
In regard to an isolated grounding type receptacle, the reason the insulated isolated grounding conductor is purposely NOT bonded to the outlet box is _____.
```
A.
the reduction of electrical noise
B.
preventing the circuit breaker from tripping in the event of a ground-fault
C.
ensuring the circuit breaker will trip in the event of a ground-fault
D.
the reduction of voltage-drop
```
A.
| the reduction of electrical noise
45
```
What is the LEAST depth of contact with the earth needed for a structural support member of a building or structure to be permitted to be used as a grounding electrode regardless of concrete encasing?
Question content area bottom
Part 1
A.
6 feet
B.
10 feet
C.
8 feet
D.
20 feet
```
B.
| 10 feet
46
```
Where used outside of a building, aluminum or copper-clad aluminum grounding electrode conductors shall NOT be terminated WITHIN _____.
Question content area bottom
Part 1
A.
18 inches of the earth
B.
3 feet of the earth
C.
24 inches of the building
D.
6 feet of the building
```
A.
18 inches of the earth
see 250.64(A)(3)
47
Bonding Jumpers are covered in NEC Table.....
Table 250.102(C)(1)
48
The two types of grounding are __
system grounding and equipment grounding
49
Systems less than 50V are required to be grounded if the supply voltage to the transformer exceeds ___ to ground
150V
50
Circuits that cannot be grounded include certain circuits for cranes, electrolytic cells, secondary circuits on lighting systems, and isolated power systems in
healthcare facilities
51
Grounding methods include an underground water pipe in direct contact with the earth for more than ___
10'
52
The size of the GEC is based on the ___
service entrance conductor
53
The size of the EGC is based on the
breaker that feeds that circuit
54
The size of the bonding jumper on the supply side is based on the size of the ___ in each raceway
service conductors
55
The two main purposes of a neutral in a grounded system are to
1. permit utilization of line-to-neutral voltage
| 2. create a low impedance return path for fault current to facilitate operation of the overcurrent device
56
Equipment grounding refers to connecting the normally non-current carrying metal parts of equipment to the system grounded conductor and/or ____
the grounding electrode conductor
57
A transformer-supplied system operating at less than 50V if the supply voltage to the transformer exceeds ___
150V to ground
58
To be effective, a grounding system must limit the voltage on the electrical system and protect it from ___
voltage surges
59
Service conductors are sized using Table...
310.16
60
The metallic noncurrent-carrying parts of an electrical system are bonded together to ensure ___
the proper operation of overcurrent devices in the event of a ground fault, and to prevent differences of potential btw different components
61
The size of the equipment grounding conductor is based on the
breaker
62
The main bonding jumper is sized based on the size of the _____.
a) service conductors
b) feeder conductors
c) largest motor load
d) largest overcurrent protective device
a) service conductors
63
Worn motor bearings are most likely to result in a
a. temporary overload
b. sustained overload
c. short circuuit
d. ground fault
sustained overload
64
Where in the NEC do you find circuit breaker applications?
NEC 240.85
65
Every circuit breaker must have its interrupting rating shown on the breaker, unless rated for ___
5000A
66
What is the highest voltage rating for circuit breakers used on DC systems that UL recognizes?
600V
67
Where is the ampere rating located on the circuit breaker?
on the handle
68
What is normally the highest short circuit current in residential applications?
10,000A
69
When does the NEC allow you to use Edison-base fuses?
for replacements in existing installations
70
Overloads are often caused by _____.
a) wires crossing
b) motors starting
c) a wire touching a metal frame
d) a bare conductor contacting a metal tool
a wire touching a metal frame
71
Which of the following is TRUE regarding overload current?
a) Overload current is confined to normal conductive paths.
b) An overload is the same as a short circuit.
c) An overload is an unintended current path.
d) Protective devices must respond to all overloads.
protective devices must respond to all overloads
72
Circuit breakers and fuses operate in a similar manner as a boiler's _____.
a) expansion tank
b) pressure relief valve
c) heat exchanger
d) burner
pressure relief valve
73
Which of the following is TRUE with regard to circuit breakers?
a) The interrupting capacity is based on the system load.
b) The interrupting capacity is the same for each voltage level.
c) The interrupting capacity is based on its rated voltage.
d) The interrupting capacity is the same for each frequency.
b. the interrupting capacity is the same for each voltage level
74
The interrupting rating of an FH-type circuit breaker is _____.
a) 5,000A
b) 10,000A
c) 30,000A
d) 65,000A
65000A
75
```
A device that trips when a fault current to ground is 6mA or more is designated by UL as
_____.
a) Class A
b) Class B
c) Class H
d) Class R
```
Class A
76
Which of the following is TRUE regarding a dual-element fuse?
a) It is a single-use only device.
b) It cannot be used in circuits subject to temporary overloads.
c) It contains a fuse link connected in series with an overload element.
d) It should be oversized to prevent nuisance trips.
c. it contains a fuse link connected in series with an overload element
77
Type S fuses are available in sizes up to _____.
a) 30A
b) 60A
c) 100A
d) 225A
30A
78
Which of the following types of drawings helps when sizing fuses for a given application?
a) Single-line schematic
b) Large-scale detail
c) Building elevation drawing
d) Floor plan
a single line schematic
79
Cartridge fuses used for branch circuit protection must be marked with the ampere rating,
interrupting rating (if other than 10,000A), and the _____.
a) date manufactured
b) dimensions
c) expiration
d) voltage rating
voltage rating
80
```
The time-current relationship for a number of overcurrent devices connected in series is
known as _____.
a) switching
b) looping
c) stringing
d) coordination
```
Coordination
81
Motor nameplates shall include the rated horsepower if ____ HP or more
1/8 HP (430.7)
82
The ____ branch circuit is that point from the last fuse or circuit breaker in the circuit out to the motor
motor
83
conductors supplying a single motor shall have an ampacity of ____ % the FLC rating as indicated on the appropriate FLC table
125%
84
The ___ is the device in a motor circuit which turns the motor ON or OFF
controller (430.2)
85
A ____ is an assembly of one or more sections with a common power bus and primarily containing motor control units
motor control center
86
What is askarel
A generic term for a group of nonflammable synthetic chlorinated hydrocarbons used as electrical insulating media
87
At what voltage do you need an arc flash label on service equipment
1000A plus. Other than dwelling units.
88
Reconditioned equipment shall be marked with the following
A) name of reconditioned
B) date of reconditioning
C) term reconditioned or similar
Original listing mark shall be removed
89
Working space is impeded if open doors limit access to less than X wide and X high
24" wide and 6.5' tall
90
In straight pulls thru junction boxes for 4g or larger, the length of the box shall not be less than X times the size of the largest raceway
8
91
For 4g or larger, with angle pulls, u pulls, or splices in j boxes, the distance between each raceway shall not be less than X time the trade size of the largest raceway
6
92
What is the resistance of copper at 75deg C
12.9 ohms per mil foot
93
What is the area of #12 wire
6530CM
94
What is the K constant for copper
12.9
95
What is the K constant for aluminum
21.2
96
Warehouse lighting minimum
1.7VA/ft sqd
97
Minimum lighting load in a store
1.9 VA per sq ft
98
Lighting load min in a house
3VA per sq ft
99
100
Formula for output watt
Output watts = hp x 746W
101
Formula for horsepower
Horsepower = output watts / 746W
102
Motor fuel dispensing systems shall be equipped with one or more disconnects. Such devices or disconnects shall be located not less than X or more than X feet from the dispensing devices they serve
Not less than 20' or more than 100'
103
Which conductors shall be disconnected at motor fuel dispensing discos
Ungrounded and grounded conductors. Not EGCs
104
Equipment less than X ft above the floor that might arc shall be of the totally enclosed type
12'
105
Exposed runs of AC cable shall closely follow the ____ of the building finish or of running boards
Surface
106
How many VA per linear foot shall be included for a load calc for show window lighting
200VA/linear foot
107
What is true power
True power is the electrical energy consumed in a circuit supplying resistive loads like incandescent lighting and resistive heating. P=EI
108
What is apparent power
apparent power is the amount of electrical energy supplied to a load, not the energy used by the load
109
Acceptable to the authority having jurisdiction
Approved
110
Recognizable as suitable for the specific purpose, function, use, environment, application, and so forth, where described in a particular code requirement
Identified
111
Equipment or materials to which has been attached a label, symbol, or other identifying mark of an organization that is acceptable to the AHJ.....
Labeled
112
Equipment, materials, or services included in a list published by an org aceptable to the AHJ
Listed
113
How many VA per outlet
180
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