Final 1st semester 2nd year
Multiconductor cables shall be permitted for nonincendive field wiring in Class III locations where the insulation thickness is ____ mm or greater.
.25 NEC 503.10(A)(4)(3)
Refer to Figure 201.2. The nominal voltage between conductors Q and R is ___ volts.
0
Five isolated ground 120-volt receptacles are to be supplied power from a 120/240-volt, 1Ø, 3-wire panelboard. Each receptacle is on a dedicated (individual) branch circuit. You installed one metal conduit and will connect the ungrounded conductors to breakers 2, 4, 6, 8, & 10. Per the NEC®, the fewest number of grounding conductors you can install in the conduit is ___.
1 NEC 406.3(D)
Quadruplex service-drop conductors of 120/240-volts, 3Ø, 4-wire where passing over a sidewalk must maintain a minimum clearance of ___ feet above final grade.
12 230.24(B)(2)
Stems of metal conduit for pendant luminaires in Class III, Division 2 locations shall be braced against lateral displacement if the stems are longer than ______ inches.
12 NEC 503.130(C)
Refer to Figure 203.4. This 120/208-volt, 3Ø, 4-wire service supplies an attorney's office. The minimum clearance at is ___. The overhead conductors are quadruplex cable and passes over the driveway that is accessible to automobiles but not trucks.
12' NEC:230.24(B)(4)
Each conduit, connected to the handy box shown above in Figure 208.31, will contain one "hot," one neutral, and one EGC. A duplex receptacle will be installed in the box. The shallowest handy box permitted for this installation is ___. All conductors are 14 AWG THHN/THWN.
2 1/8 inches deep (4 CCCs + 1 EGC + 2 for device)(2.0)=14 in cubed=> 2 1/8 inches deep will work NEC 314.16
When performing load calculations in Article 220, the load for household electric clothes dryers in a dwelling unit(s) shall be ___ watts (volt-amperes) or the nameplate rating, whichever is larger, for each dryer served.
5000 NEC 220.54
60 cycle (hz) AC voltage is positive ___.
60 times in a second
Receptacle ___, shown below, is rated at 20 amps.
answer is picture
If a motor and the motor controller (starter) are located in the same room and 26 feet apart, these ___ considered to be within sight (of each other) per the NEC®.
are NEC: 100_In sight From
Receptacle ___, shown below, is rated at 15 amps.
both NEC 406.7
Where lubrication and vehicle servicing is done at minor repair garages, the space below the floor level in a ventilated pit shall be ___. Exhaust ventilation is provided at a rate of not less than 0.3 m3/min/m2 (1 cfm/ft2) of floor area at all times that the building is occupied. a. classified as Class I, Division 1 b. none of these c. unclassified d. classified as Class II, Division 2
none of these
Capacitors in series add like resistors in ___.
parallel
A service disconnecting means can be installed outside a building in a location that is ___.
readily accessible NEC: 230.70(A)(1)
The basic law of magnetism states that like poles (north and north, for example) ___ each other.
repel
Which of these trade size 11/4 raceways has the smallest cross-sectional area?
schedule 80 pvc
Where circuit breaker terminals or safety switch lugs are marked on the equipment (or included with installation instructions) with a tightening torque by the manufacturer, this torque is required to be applied to the connections.
true NEC 110.14 / NEC 110.14(D)
You need to move some breakers around in a panel to make room for a 3-pole breaker. You can move breaker #1 to an empty space near the bottom but the "hot" will then be too short. Does the NEC® permit you to just splice a short piece of wire onto the "hot" with wire nuts so you can then reach the relocated breaker?
yes NEC 408.2/NEC 312.8
A certain piece of equipment is to be connected with SOO flexible cord. The equipment requires 1 grounded and 2 ungrounded conductors. Of the sizes listed below, what is the smallest AWG size cord that can be used to connect the equipment? All conductors should be counted as a current carrying. The maximum load on any one conductor is 17 amps.
13 NEC 410.10(D)(1)
A DMM is set for a voltage measurement and the range is set to 600 V. If the voltage to be measured is 277 volts, the LCD will display ___.
277
For temporary installations, required tests for the assured equipment grounding conductor program shall be performed at intervals not exceeding _______ month(s).
3 590.6(B)(2)(a)(3)(d)
The minimum working clearance at Point X in Figure 201.15 is ___ feet. The panel is 120 /208-volt, 3Ø, 4W.
3 NEC 110.26(A)(1)
If the window is openable, the minimum clearance at C in Figure 203.6 is ___.
3 feet NEC 230.9(A)
After the minimum ampacity of the service has been calculated, Table ___ and 310.14 are used to determine the size of feeder or service-entrance conductors.
310.16
The smallest size copper wire permitted to be used as a main bonding jumper in a 200-A main breaker panelboard is ___ AWG. The panel is fed from a transformer with one set of 3/0 AWG wire.
4
AC cable is the wiring method to be used above in Figure 208.3. The maximum distance permitted between support #7 and support #8 is ___ feet.
4 1/2 NEC320.30(C)
Refer to Figure 205.10. The 200-A safety switch contains 175-amp fuses. The raceways used between the switch and the motor contain three 4 AWG conductors. The minimum size of the EGC between the safety switch and the motor is ___ AWG.
6 NEC: 250.102(D)/250.122(TABLE)
One receptacle is to be installed on a dedicated (individual) branch circuit. A receptacle rated at ___ amps could be used where the circuit is connected to a 40-A circuit breaker. I. 40 II. 50
Either I or II NEC 210.21(B)(1)/NEC 210.21(B)(3)(Table)
Which of the following is a type of circuit condition? I. short circuit II. overload
I & II
Service equipment shall have an ampere interrupting rating (AIR) ___ the fault current available at the service location. I. greater than II. equal to III. less than
I or II only NEC 110.9
The compressor nameplate reads: 240V 1Ø 60 Hz. Which of the following safety switches is (are) permitted to be used as the disconnecting means for the air compressor shown above in Figure 201.13? I. 250-volt, 2-pole II. 600-volt, 3-pole III. 250-volt, 3-pole
I or II or III NEC 110.4
One receptacle is to be installed on a dedicated (individual) branch circuit. A receptacle rated at ___ amps could be used where the circuit is connected to a 50-A circuit breaker. I. 40 II. 50
II only NEC 210.21(B)(1)/NEC 210.21(B)(3)(Table)
Where installed in a 3-pole, 600-volt fused safety switch, the minimum number of fuses required to protect a 208-volt, 1-ph, 2-wire branch circuit is ___.
NEC 240.15(A)
Overcurrent can be a result of ___. a. short circuits b. ground faults c. overloads d. all of these
all of these NEC: 100_overcurrent
Per the NEC®, a convenience receptacle is required to be installed on the same level and within 25' of an air conditioning unit that is installed on the roof of ___. a. a single family dwelling b. a shopping center c. an apartment building d. all of these e. none of these
all of these NEC: 210.63
The illuminated marquee sign for a theatre would be considered to be a ___ load.
continuous
Illustration I in Figure 204.8 ___ satisfy the requirements of 240.21(B)(5).
does NEC: 240.21(B)(5)
Which of the following safety switches is (are) permitted to be used as the disconnecting means for a 240-volt, 1Ø water heater? I. 250-volt, 3-pole II. 600-volt, 3-pole
either I or II NEC 110.4
A ___ is a device that attracts iron and steel because of the molecular alignment of its material.
magnet
___ is a force that interacts with other magnets and ferromagnetic materials.
magnetism
Fluorescent luminaires are connected end-to-end as shown below. The "Home Run" conduit contains circuits HA-16, 18, 20 (3 "hots" + 1 neutral) and nightlight (NL) circuit HA-2. All of these circuits originate in a 277/480-volt, 3Ø, 4-W panelboard. These conductors pass through the luminaires and the circuits serve the luminaires as indicated on the illustration.
this installation is permitted by nec 410.64(C)
Circuit impedance (Z) consists of both the resistive and reactive components of a load.
true
Where a service (meter and fused safety switch) is built on a rack that is located 200' from the building it serves, the rack is considered a structure per the NEC®.
true
Regardless of circuit rating, whenever flexible metal conduit is used to connect a motor, a separate grounding conductor is required to be installed with the flex.
True NEC: 250.118(5)(d)/NEC 348.60
Which 2 AWG conductor has a higher resistance?
aluminum NEC: Ch. 9-t.8
If the dimmer is installed as shown at I in Figure 201.9, ___ will occur.
an overload
The cable connector shown at ___ is a compression type connector.
answer is pic
The conduit body shown above at ___ in Figure 208.19 is a Type LB.
answer is pic
A 120/240-volt, 1Ø, 3-wire multiwire branch circuit is connected to a "split-wired" double single-pole switch as shown here. These are sometimes called dougle or stack switches. Each of the two switches (mounted on the same yoke) will serve a separate 120-volt lighting load. The branch-circuit OCPD/disconnect for these circuits is permitted to be ___. a. a 2-pole circuit breaker b. two single-pole circuit breakers with identified handle ties c. a 2-pole fused safety switch d. any of these e. none of these
any of these NEC: 210.4(B)
Rigid Metal Conduit (RMC) is generally made of galvanized steel or aluminum but special applications, such as for swimming pools or in chemical plants, may require the use of ___ conduit. a. bronze b. stainless steel c. either a or b d. neither a nor b
either a or b
Refer to Figure 210.7, shown above. The conductors between Panel A1-1 and Panel A1-2 are ___ conductors.
feeder
In Figure 210.8 the conductors that supply power to Panel II are ___ conductors.
feeder NEC 100_Feeder
The attachment cord cap, shown in Figure 211.3 (above), is connected to an incandescent lamp. When the cord cap is plugged into a wall receptacle, "tab" (or prong) I is connected to the ___ conductor of the branch circuit.
grounded
In a run of conduit, when couplings and connectors are loose this will ___ the amount of time required for a circuit breaker to open when an overload occurs.
have no effect on
Refer to Figure 210.6, shown above. The conductors connected to the terminal lugs are 350 kcmil. The minimum wire bending space required at II is ___ inches. These lugs are of the lay-in type. a. 12 b. 5 c. 10 d. 8 e. none of these
none of these 12" - 3" = 9" nec: 312.6(B)(Table) Note 2
Where run outside on the wall of a building, a grounding electrode conductor to a metal water pipe shall be ___. A driveway runs along this wall. a. at least a 6 AWG and supported b. at least a 4 AWG and supported c. at least an 8 AWG and in properly-supported Schedule 40 PVC d. none of these is a suitable option
none of these is suitable option
240.21(B)(1) requires that tap conductors, where not over 3 m (10 feet) in length, have an ampacity of at least ___ the rating of the overcurrent device protecting the feeder conductors.
one-tenth NEC: 240.21(B)(1)
Refer to Figure 208.34. The smallest (volume) junction box that can be used in the installation shown below is a___. Conduits #1 and #4 each contain twenty-four 10 AWG wires. Conduits #2 and #5 each contain twelve 6 AWG wires. Conduits #3 and #6 each contain sixteen 8 AWG wires. Conduits #7 and #10 each contain thirty-two 12 AWG wires. Conduits #8 and #11 each contain twelve 8 AWG wires. Conduits #9 and #12 each contain twenty-eight 12 AWG wires. All conductors are "wire nutted" inside the box. Additionally, each conduit contains a ground that is equal in size to the circuit conductors..
10" x 10" x 8" deep
Refer to Figure 203.4. For a 120/240-volt, 1Ø, 3-wire service, the minimum clearance at is ___. This area is not accessible to vehicles and the overhead conductors are triplex cable.
10' NEC:230.24(B)(4)
You are to surface mount 128' of EMT on a wall between two boxes as shown above in Figure 208.11. You will use 1-hole straps to securely fasten the EMT to the wall. The minimum number of straps required is ___.
14
What is the maximum number of #4 THHN/THWN conductors that can be installed in a run of 2-inch IMC?
17 NEC ch. 9-t. 4
In a circuit with 10 ohms resistance and 15 ohms inductive reactance, the impedance is ___ .
18.0277
The compressor nameplate reads: 240V 1Ø 60 Hz. Per the NEC®, the minimum number of fuses that are to be installed in the fused safety switch shown in Figure 201.13 is ___.
2 NEC 240.15(A)/ NEC
2" EMT is installed between two boxes for several circuits. The maximum area that can be occupied by the circuit conductors is ___ sq. in where the boxes are 16 inches apart.
2.013 NEC Ch 9-T. 4
The minimum branch-circuit rating for an individual branch circuit that is used to supply a fastened-in-place appliance is ___ amps. The marked rating (equipment nameplate) on the appliance is 24 A. The appliance is continuously loaded.
30 24 A x 125% = 30A
For the 277/480-volt panelboard shown in Figure 201.20, the minimum width of the working space directly in front of the panelboard is ___.
30" NEC 110.26(A)(2)
Refer to Figure 201.21. The minimum clearance from the 277/480-volt panelboard to the opposite wall is ___ inches. The wall opposite the panelboard is made of CMUs (cement blocks).
42 NEC 110.26(A)(1)
Refer to Figure 205.11. The 200-A safety switch contains 125-amp fuses. The raceways used between the switch and the 3Ø motor contain three 2 AWG conductors. The minimum size of the EGC between the safety switch and the motor is ___ AWG.
6 NEC: 250.102(D)/250.122(TABLE)
MC cable is used to connect a 2 x 4 lay-in fluorescent luminaire to a "home run" box as shown above in Figure 208.2. The length of the cable between the box and the luminaire is 26 feet. The maximum distance between the luminaire and support #2 is ___.
6 ft
A stairway between the 1st and 2nd floors of an office building with ___ to control the stairway lighting will not violate the NEC®. I. a 3-way switch at the 1st floor & a 3-way switch at the 2nd-floor landing II. a single-pole switch at the 1st-floor landing III. a single-pole switch at the 2nd-floor landing
I or II or II NEC 210.70(A)(2)(3) N/A
Refer to Figure 210.8, shown above. Panel ___ is a subpanel.
II & III only
A steel plate is required to protect ___ where it is installed through wooden framing members. A 1? inch clearance from the edge of the framing member can NOT be maintained I. EMT II. Schedule 40 PVC III. RMC
Neither I nor II nor II
240.21(B)(1) requires that tap conductors, where not over 3 meters (10 feet) long, have an ampacity that ___. I. will be able to carry the current drawn by the load II. is at least 1/3 the rating of the overcurrent device protecting the feeder conductors III. is at least 1/10 the rating of the overcurrent device protecting the feeder conductors
I & III only NEC: 240.21(B)(1)
Where a calculation results in an ampacity requirement that does not match the standard rating of an overcurrent protective device, which of the following is permitted?
Select an OCPD with the next higher standard ampere rating NEC 240.4(B)