Q and A sheet Flashcards
1
Q
What does FLC mean?
A
Full load current
2
Q
An electrical device that consists of a frame, plunger, and uses an up down motion to operate is called a what?
A
solenoid
3
Q
Types of equipment grounding conductors?
a. rigid metal conduit
b. Listed liquid titght flexible metal conduit
c. flexible metal tubing
d. Electrical metal tubing
A
4
Q
Class 3 inherently limited power source circuits are not rated for over how many volts?
A
100 volts
(ch9 table 11.B)
5
Q
How many #10 RHW* conductors can be placed inside a 1” ENT pipe?
A
10
(Annex C Table C.2)
6
Q
What size RMC pipe is needed for the total square inch area (including insulation) of: (4) #8 THHN and (6) #10 THHN wires?
A
1 inch
(Table 4 and Table 5)
can’t use annex C…
8=.0366 x 4, 10=.0211*6…
over 2 wire = 40% = 1 inch
7
Q
How many #8 THHW, compact conductors can be placed inside 1” EMT trade size conduit?
A
6
Annex C Table C.1A
8
Q
An electrical tubing nipple is defined as tubing ___ or less in length and may be filled to a maximum of ___ % of the total available internal square inch area of the tubing.
A
24”, 60%
Ch9 Table 1 Note 4
9
Q
Max conductor fill rate for all types of conduits (over 24” length) with over 2 conductors, including cellar concrete raceways, is?
A
40%
Ch9 Table 1
10
Q
Hybrid communication wire shall have a min voltage of ___ volts?
A
600v
800.179(i)
11
Q
Communication wire shall have a min voltage of ___ volts?
A
300v
800.179
12
Q
How many inches has to be separated between class 2 and class 3 circuits?
A
2 inches
225.136(i)
13
Q
Where a portable optional standby source is used as a ___ it shall be grounded to a grounding electrode
A
separately derived system
know 202.11a-b
14
Q
Key things to know from Ch 6:
A
Office furnishings,
x-ray equipment,
solar photovoltaic systems,
Electric vehicle charging systems,
swimming pools,
welders (arc and resistance)
15
Q
Direct Current Turbines shall be installed in: MC, RMC, IMC, BS?
A
MC
One Q on DC Turbine
16
Q
Photovoltaic supply can be run in what type of raceway?
A
MC
690.31(g)(2)
17
Q
Bonding to a pool grid must have what type of devices?
A
Pressure devices
680.26, 250.8a
18
Q
In office furnishings, the flexible power cord shall not exceed __ in length.
A
2 feet
Know 605.9a-d, one Q
19
Q
Neon tubing exceeding 1000V shall not be installed in?
A
Dwelling Units
600.31(l)
20
Q
Commercial buildings with accessibility to pedestrians shall provide at least one ___ receptacle
A
20 amp
600.5A
21
Q
What size branch circuit is required for a sign outside a commercial pedestrian door?
A
20 amp
600.5(A)
22
Q
For photobvoltaic systems, what cannot be connected to the supply side
A
non-overcurrent light (device)
23
Q
Indoor receptacle for an electric vehicle charging stations shall be mounted at a minimum height of?
A
18 inches
625.50
24
Q
Outdoor receptacle for an electric vehicle charging stations shall be mounted at a minimum height of?
A
24 inches
625.50
25
Key things to know for Chapter 5:
Commercial garages (major v minor),
recreational vehicles,
healthcare facilities,
marinas and boatyards
26
A boat hoist receptacle shall be mounted not less than ____ above the deck surface of the pier and not below the electrical datum plane on a fixed pier.
12 inches
555.19
27
For a mobile home, the grounded conductor shall be ____
insulated
550.16(A)(1)
28
In general care areas, each patient bed shall be provided with a min of ____ receptacles.
8
517.17b
29
In critical care areas, each patient bed shall be provided with a min of ____ receptacles.
14
517.17b
30
Disconnecting means for a mobile home shall be a min of what height?
2 feet
550.11A
31
Anesthetizing locations shall be classified as ____
class 1 / division 1,
517.60(a)(1)
32
Anesthetizing locations shall extend upwards to a level of ____
5 feet
517.60(a)(1)
33
What type of cable can’t be used as a ground for critical and EM branch circuits of a hospital?
Isolated ground
517.19
34
In health care facilities, the EM light circuit shall wired on the ___
life safety branch circuit
517.32A
35
Occupancy of ____ people or more must be wired in MC or conduit
100
518.1
36
Liquid propane indoor storage tank are class ___ division ___ within 5’ of tank
Class 1 Division 1
514.3(B)(2)
37
In gas stations, how far from the floor up is class 1 div 1?
18in
514.3(b)(1)
38
An outdoors gasoline dispensing device up to 18” above grade level within 20” horizontally of any edge of the enclosure is ____?
Class 1 Division II
514.3(b)(1)
39
What is the max surface temp of T2A?
536
500.8C
40
When do you need/not need tamper proof receptacles?
Need: elementary school. Don’t need: high school, warehouse
406.12
41
What type of receptacle do you need for a car wash?
Wet location
406.???
42
Disconnections means for motor circuits rated 600V or less shall have an ampere rating not less than ___ percent of the FLC rating?
115%
430.110A
43
By what percent is the FLC of a wound rotor motor multiplied to determine the motors minimum OCPD using inverse time breaker?
150%
430.52
44
Fuses are put on the current carrying conductors as well as the grounded conductor if it is what type of motor feeder?
3 wire/ 3-phase
430.36
45
Conductors supplying several motors shall have an ampacity of not less than the sum of the motors plus ___ percent of the highest rated motor?
25%
430.24
46
A conductor supplying a single motor used in continuous duty application shall have an ampacity of ____ percent of the motor’s FLC?
125%
430.22
47
Branch circuits supplying two or more outlets for fixed electrical space heating equipment shall be rated for not over how many amps?
30 amps
424.3(A)
48
What type of cable does a garbage disposal cord have to be made of?
listed for use
422.16(B)(1)
49
Electrically operated kitchen waste disposers shall be permitted to be cord and plug connected with a flexible cord of not more than how many inches and not less than how many inches?
36 inches, 18 inches
422.16(b)(1)(2)
50
A furnace has to be run on what type of circuit?
Individual branch circuit
422.12
51
What is the minimum space between a recessed fixture and thermal insulation?
3 inches
410.116B
52
Light poles shall have a handhole of not less than ___
2” x 4”
410.30(B)1
53
What color triangle marking will be on noise cancelling outlet?
orange
406.3(D)
54
A general use snap switch shall be connected to no more than what percent of its rated use?
80%
404.14(A)3
55
Key things to know Chapter 3:
Anything dealing with raceways: distance between supports, termination points, installation…
Ampacities tables are in this chapter,
article 393: low voltage suspended ceiling power distribution systems
service is 75 deg F always.
56
What is the max number of conductors allowed in an auxiliary gutter?
30
366.22(a)
57
Type RTRC shall be permitted to be unsupported where the raceway is not more than __ long, and remains in unbroken length, and terminated in an outlet box.
3’
355.30(A)
58
What is the expansion rate of 250 feet of PVC that goes from a temperature change of -20 deg F to 80 deg F.
10.15
{4.06*250/100}
352.44
59
What is the max distance between supports for a 1” rigid PVC?
3 feet
352.30
60
10 feet of equipment grounding conductor cannot be made of what?
FMC
342.20A/350.118 7b
61
For gas stations, ____ can be used as a raceway under class 1 division 1, under 8 inches of fill dirt.
RMC
344.10C
62
What type of cable is not approved for service entrance cable?
UF
340.12
63
What is the temperature rating for the conductor of type NM CABLE?
60 C
344.80
64
What is the max distance from a panel that a type MI cable must be secured?
6 feet
332.30
65
Floor boxes must be made of what?
UL Listed
314.27(b)
66
A Fixture box shall be independently supported if the fixture weighs more than how many pounds?
50 lbs.
314.27(A)2
67
Type NM cable shall be secured how many inches from a non-metallic box if there is no clamp?
8 inches
3114.17C
68
Type NM cable shall be secured how many inches from a metallic box if there is no clamp?
12 inches
3114.17C
69
What is the max number of #14 conductors allowed in a 4” x 2 1/8” metal octagonal trade sized box?
10
314.16(A)
70
What is the required free space in a junction box for a #10 conductor?”
2.5 cubic inches
314.16(b)
71
Type NM cable shall be approved for installing under the lower edges of a joist in crawl spaces if the wire is at least three --- AWG or two ---- AWG
three #8AWG or two #6AWG
334.15(c)
72
When using a round box where conductors or connectors require the use of a locknuts or bushing are to be connected, to what part of the box can they not be connected?
side of the box
314.2
73
What type of conductor is rated for direct burial?
UF
310.104a, 340.10
74
What is the min size THW conductor that can be used to supply a 200 amp single phase commercial building?
3/0 copper
310.15(b)(16)
75
A Single-family dwelling has a 100-amp service. What size feeder will be required to supply a 75-amp electric space heater and a 25-amp air conditioner?
#2
…non coionidental, use largest = 75A..feeder less than 100 = 60 deg, = #2
310.15(b)(16)
76
What is the overcurrent protection for 8 #12 THNN conductors in a ½ in pipe?
20 amp
…pg 148:8=70%, pg 150…#12 = 30A x .7 = 20A
77
What is the min size wire needed to supply a 100-amp single phase 3 wire main service on a mobile home?
#4 copper
310.15(b)(7)
78
What is the smallest size conductor you can run in parallel?
1/0
310.10(H)(1)
79
At what rated voltage does direct burial cable have to be shielded?
2,000V
310.10(f)
80
When direct burial exit the ground, what shall they be enclosed in?
Raceway
300.5(D)(4)
81
The minimum distance any edge of a stud must be from the edge of a hole for nm cable is ___
1 ¼ inches
{300.4(a)(1)}
82
What is the minimum size copper-clad grounding electrode conductor needed for a 200 amp, single phase dwelling copper feeder?
2 AWG
{310.15(b)(17)}{250.66}
…. 83% rule: 100-400A, take amp and multiply by 83%...200x.83 = 166A = 2.0… 2.0 = 2AWG from 250.66. pg150: 310.15.b.17…pg 119, pg 155?, 1q on copper, 1q on copper clad, 4Q ampacity
AWG {310.15(b)(17)}{250.66}
83
What is the minimum size main bonding jumper for an 800 Kcmil service entrance conductor?
2/0
250.102C(1)
84
When a metal enclosure is required to protect the grounding electyrode conductor, the enclosure has to be bonded to ____ at both ends.
Grounding electrode conductor
{250.64(e)}
85
What size grounding electrode conductor must always be protected from physical damage?
#6 or larger
{250.64(b)}
86
What is the minimum space between ground rods?
6 feet
{250.53(B)}
87
A ground rod shall be at least how many inches in diameter?
5/8 inch
{250.52(5)(b)}
88
How many feet of a rod electrode need to be in contact with the earth?
8 feet
{250.53(g)}
89
What is the minimum size wire for a ground ring?
#2 copper
(250.52(a)(4)
90
A concrete encased electrode with electrically conducted coated steel reinforcing bars shall be at least ____ in continuous length
20 feet
{250.64(B)}
91
A concrete encased electrode with electrically conducted coated steel reinforcing bars shall be at least ____ in diameter
½ inch
{250.64(B)}
92
High impedance ground systems operate at a minimum of what voltage?
480 volts
{250.36}1
93
The green screw in a main panel enclosure serves as what?
Main bonding jumper
{250.28B}
94
What is the smallest size grounded conductor you can run in parallel?
1/0
{250.24C}
95
A grounding electrode conductor may be spliced together by: welding, cable clamps, exothermic welding, or all of the above?
Exothermic welding
{250.8(A)(4)}
96
A type S fuse is installed in an Edison base fuse holder for what primary reason?
Non-interchangeable
{240.53(B)}
97
What is the minimum height of a SE (service entrance?) conductor rated 600 volts going above a pedestrian sidewalk?
15 feet
…watch out for verticle clearance trick question voltage….
230.24(B)
98
What the maximum number is of disconnects at the main service?
Six
{230.74?}
99
What is the minimum service disconnect of a commercial building?
60 amps
{230.79(D)}
100
What is the minimum service disconnect of a residential single family dwelling?
100 amps
101
What cannot be connected to the supply side of a service disconnect
230.82, 1-9…ground …check code ref
102
When fuses serve as overcurrent protection, a disconnecting means shall be supplied on the line side of all fused circuits that exceed 160 volts if the fuses are accessible to who?
Other than qualified personnel
{240.40}
103
Edison base fuse holders shall be a maximum of what voltage?
125 volts
{240.51a}
104
Edison base fuses shall not operate at over how many amps?
30 amps
105
Does a vehicle garage require illumination under the illuminated entryway rule?
No
{210.7(D)(A2)
106
Does a man door require illumination under the illuminated entryway rule?
Yes
{210.70(D)(A2)
107
Does a service door require illumination under the illuminated entryway rule?
Yes
{210.70(D)(A2)
108
General branch circuit lighting load for a hospital shall be calculated at ___ watts per square ft?
2 Watts
{220.12}
109
In dwelling units, new additions to the lighting branch circuit shall be calculated in accordance with 220.12 when over ____ sq ft
500 sq ft
{220.16(A)1}
110
Where SE (service entrance?) cable enters the building, the conduit has to be ____
Sealed
{225.27}
111
The conductors for festoon lighting shall be supported by messenger wire in all spans exceeding ___ ft
40 ft
{225.6(B)}
112
What is the minimum service rating for a single-family dwelling with 6 or more two-wire branch circuits?
100 amps
{230.79(C)}
113
Circuit breakers used as switches in 120-volt fluorescent lighting shall be marked as ____
Most correct answer is C. A and B (HID and SWD)…only for florescent lighting
{240.83(d)}
114
The width of the 120/240 volt panel working area shall be a minimum of ___ ft, and the door shall be open able to at least 90 deg.
2.5 ft
{110.26(a)2}
115
Manhole covers shall have a minimum weight of ___
100 lbs
{110.73}
116
A 240-volt boat hoist receptacle has to be ____
GFCI Protected
{210.8C)
117
Non-dwelling unit receptacles installed in/on the ___ shall be GFCI protected: a. rooftops, b.outdoors, c. dedicated snow melting equipment, d.sinks?
Rooftops, outdoors, and sinks
118
What is the minimum rating for a laundry circuit in a single family dwelling?
20 amps 1500watts
{210.11C2}, {220.12J, {220.52B}
119
A receptacle on an individual branch circuit can be rated for what percent?
100%
{210.22}
120
What size branch circuits shall supply only non-lighting loads?
larger than 50 amps
{210.24)
121
What type of lamp holder shall be connected to a load in excess of 20 amps?
Heavy duty
{210.24)
122
The laundry outlet shall be installed within how many feet of the designated applicate location?
6 ft
{210.45(C)}
123
Receptacle outlet in the first floor shall not be counted as part of the required number of wall receptacle outlets unless located within how many inches of the wall?
18 inches
{210.52(a)(3)}
124
Types of equipment grounding conductors?
a. rigid metal conduit
b. Listed liquid titght flexible metal conduit
c. flexible metal tubing
d. Electrical metal tubing
A & D: electrical metal tubing and
rigid metal conduit
125
What is the cross sectional area in circular mils ofa solid wire with diameter of 0.102?
10,380
126
A restaurant has 15.5 foot plug strip for all their television systems which are likely to be used at the same time. What is the VA?
2880 VA…
15.5/1, round up = 16, X 180 = 2880
{ch9 table 8…3-5 questions on ch9table8, anne c, ch9table5, ch9table4}…
127
What if the TV’s are unlikely to be used at the same time, 15.5 foot plug strip.
720VA
unlikely: 15.5/5 = 3.1, round up to 4, x180 = 720
{ch9 table 8…3-5 questions on ch9table8, anne c, ch9table5, ch9table4}…
128
An apartment has 8 water heaters at 800 watts, what is the VA?
4800VA
of appliances x nameplate x demand = 8x800x.75 = 4800VA
129
What is the expansion rate of 500ft type RTRC that goes from 80 deg F to 50 deg F
2.7
Temp change = 30 deg C….54/100ft from table… (.54/100)*500=2.7
{355.44}
130
240 volt to ground, 200 amp panel in condition 3 needs a minimum front clearance of ___ ft
4ft
{110.26(a)1}
131
What is the minimum clearance in front of a service panel?
3 ft
{110.26(A)1}
