EWR Unit Reviews
What size conductors are to be used for the lighting branch circuits? ______________________ AWG
14 AWG
Outdoor receptacle outlets in the dwelling in Appendix A are located ____________ in. above grade.
18 in
Name a nationally recognized testing laboratory.
UL (Underwriters Laboratories) ETL (Intertek Testing Laboratories) FM (Factory Mutual) Correct answer: All of the above
The NEC in Article 100 defines a continuous load as, A load where the maximum current is expected to continue for three hours or more.* According to 210.19(A) and 210.20(A), the branch-circuit conductors and overcurrent protection for a continuous load shall be sized at not less than ___________ of the continuous load.
125%
The minimum number of outdoor receptacles for a residence is _____________, NEC __________________.
2, NEC 210.52(E)
You will learn in Chapter 3 that residential lighting loads are based on 3 volt-amperes per ft2 (33 volt-amperes per m2). Determine the minimum lighting load required for an area of 186 m2. Do calculations for both feet squared and meters squared so you can see the difference in answers. To convert meters squared to feet squared, refer to Table 1-8.What is the feet squared for the information above?
2002 sq ft
According to NEC 210.50(C), a laundry equipment outlet must be placed within _______________ ft (m) of the intended location of the laundry equipment.
6 ft (1.8 m)
To allow for adequate conductor length at electrical outlet and device boxes to make up connections, 300.14 requires that not less than [3 in. (75 mm), 6 in. (150 mm), 9 in. (225 mm)] of conductor length be provided. This length is measured from where the conductor emerges from the cable or raceway to the end of the conductor. For box openings having any dimension less than 8 in. (200 mm), the minimum length of conductor measured from the box opening in the wall to the end of the conductor is
6 in (150 mm), 3 in (75 mm)
What is the minimum number of 15-ampere lighting branch circuits required if the dwelling has an occupied area of 4000 ft2 (368 m2)?
6.7 (7)
You will learn in Chapter 3 that residential lighting loads are based on 3 volt-amperes per ft2 (33 volt-amperes per m2). Determine the minimum lighting load required for an area of 186 m2.You know now that 186 m sq is 2002 ft sq. figure the volt-amperes for the square footage.
6006
You will learn in Chapter 3 that residential lighting loads are based on 3 volt-amperes per ft2 (33 volt-amperes per m2). Determine the minimum lighting load required for an area of 186 m2.Now you know the volt amperage for square footage is 6006 volt-amperes.Figure the volts-amperes using the square meter.
6138
When laying out a job, the electrician will usually make a layout of the circuit, taking into consideration the best way to run the cables and/or conduits and how to make up the electrical connections. Doing this ahead of time, the electrician determines exactly how many conductors will be fed into each box. With experience, the electrician will probably select two or three sizes and types of boxes that will provide adequate space to "Meet Code." Table 314.16(A) of the Code shows the maximum number of conductors permitted in a given size metal box. In addition to counting the number of conductors that will be in the box, what is the additional volume that must be provided for the following items? Enter single or double volume allowance in the blank provided.for one or more wiring devices on one yoke: _________________ volume allowance.
Double (count 2 of the largest conductors)
Practically any outlet or switch box which has a drade size of 3/4 in knockout can be used with offset bar hangers.
False
The total occupied area in square feet is multiplied by the unit load per square foot. In dwellings, the unit load per sq. ft is 6 volts-amperes per square foot (33 volt-amperes per square meter).
False
How many lighting branch circuits are provided in the dwelling used in your EWR text?
For lighting branch circuits, the load in amperes is divided by 15 amperes.
In a basement, at least one receptacle outlet must be installed in addition to the receptacle outlet installed for the laundry equipment. This additional receptacle outlet and any other receptacle outlets in the basement must be _____________ protected.
GFCI
What advantage does a 4 in. octagon box have over a 3¼ in. octagon box?
It has more space for the conductors and splices
Is it permissible to install a receptacle outlet above an electric baseboard heater?
Listed baseboard heaters include instructions that may not permit their installation below receptacle outlets. See Informational Note to NEC 210.52.
What spaces are not included in the floor area when calculating the load in volt-amperes per square foot? See NEC 220.11.
Open porches, garages, or other unfinished and unused spaces unless adaptable for future use
What dimensions are used when measuring the area of a building? See NEC 220.11.
Outside dimensions
What do the letters "PPE" stand for?
Personal Protective Equipment
How is the minimum number of receptacle outlets determined for most occupied rooms? See NEC 210.52(A).
Receptacle outlets are installed so that no point along the floor line in any wall space is more than 6 ft (1.8 m) measured horizontally from an outlet in the space. Any wall space 2 ft (600 m) or greater also requires a receptacle outlet.
When laying out a job, the electrician will usually make a layout of the circuit, taking into consideration the best way to run the cables and/or conduits and how to make up the electrical connections. Doing this ahead of time, the electrician determines exactly how many conductors will be fed into each box. With experience, the electrician will probably select two or three sizes and types of boxes that will provide adequate space to "Meet Code." Table 314.16(A) of the Code shows the maximum number of conductors permitted in a given size metal box. In addition to counting the number of conductors that will be in the box, what is the additional volume that must be provided for the following items? Enter single or double volume allowance in the blank provided.for a fixture stud: ______________________-volume allowance.
Single (Count 1 Largest Conductor Size.)
When laying out a job, the electrician will usually make a layout of the circuit, taking into consideration the best way to run the cables and/or conduits and how to make up the electrical connections. Doing this ahead of time, the electrician determines exactly how many conductors will be fed into each box. With experience, the electrician will probably select two or three sizes and types of boxes that will provide adequate space to "Meet Code." Table 314.16(A) of the Code shows the maximum number of conductors permitted in a given size metal box. In addition to counting the number of conductors that will be in the box, what is the additional volume that must be provided for the following items? Enter single or double volume allowance in the blank provided.for one or more equipment grounding conductors: __________________- volume allowance.
Single (count 1 of the largest conductor)
The space between a door casing and a window casing is 3½ in. (88.9 mm). Two switches are to be installed at this location. The space is too small for a 2-gang plate; therefore, the switches must be combination switches trimmed with a single-gang, 2-hole faceplate. Two or 3 switches are also available on a single strap or yoke for which a single-opening, decorative-style faceplate is installed.
True
What can you do to reduce or eliminate the possibility of receiving an electric shock when working on electrical circuits?
Turn off the power on the circuit you are working on, tag it and lock the disconnect in the OFF position.
When laying out a job, the electrician will usually make a layout of the circuit, taking into consideration the best way to run the cables and/or conduits and how to make up the electrical connections. Doing this ahead of time, the electrician determines exactly how many conductors will be fed into each box. With experience, the electrician will probably select two or three sizes and types of boxes that will provide adequate space to "Meet Code." Table 314.16(A) of the Code shows the maximum number of conductors permitted in a given size metal box. In addition to counting the number of conductors that will be in the box, what is the additional volume that must be provided for the following items? Enter single or double volume allowance in the blank provided.a. one or more internal cable clamps: ______________________-volume allowance.
single (Count 1 Largest Conductor Size)
The Code indicates the rooms in a dwelling that are required to have switched lighting outlets or switched receptacles. Write "yes" (switch required) or "no" (switch not required) for the following areas [see NEC 210.70(A)]:attic
yes
In an NEC reference, what does the word "shall" mean?
must
Are low-voltage systems totally safe?
no
Does compliance with the NEC always result in an electrical installation that is adequate, safe, and efficient?
no
Is it a safe practice to use a stepladder in which the spreaders have not been fully locked into position?
no
List the maximum number of 12 AWG conductors permitted in the following metal box: 4 11/16 in x 1 1/2 in square box.
13
What section of the NEC states that all listed or labeled equipment shall be installed or used in accordance with any instructions included in the listing or labeling?
110.3(B)
What size conductors are to be used for the small-appliance branch circuits? ______________________ AWG
12 AWG
What is the smallest size wire that can be used in a branch circuit rated at 20 amperes?
12 AWG wire unless otherwise permitted such as for motor branch circuits. Refer to Table 310.16, 240.4(D) and (G)
How high above the finished floor in the living room are receptacles located?
12 in to center
A junction box on a piece of European equipment is marked 200 cm3. What is the cubic inches convertion.
12.204 cu in
The total load in volt-amperes is divided by ________ volts.
120
How many lighting branch circuits are provided in the dwelling used in the EWR text? See Table 3-1 in the text.
13
Two 12-2 AWG and two 14-2 AWG nonmetallic-sheathed cables enter a box. Each cable has an equipment grounding conductor. The 12 AWG conductors are connected to a receptacle. Two of the 14 AWG conductors are connected to a toggle switch. The other two 14 AWG conductors are spliced together because they serve as a switch loop. The box contains two cable clamps. Calculate the minimum cubic-inch volume required for the box.Using the same number and size of conductors as in the problem above, but using electrical metallic tubing, calculate the minimum cubic-inch volume required for the box. There will be no separate equipment grounding conductors, nor will there be any clamps in the box.
25.50 cu in
What section of the specifications tells us the size of the service entrance to be installed for this residence?
26 Main Service
What is the size of the opening of a switch (device) box for a single device?
3 in x 2 in
What is the lighting unit load per square foot for dwelling units? See NEC 220.14(J).
3 volt-amperes per square foot (33 volt-amperes per square meter)
Two 12-2 AWG and two 14-2 AWG nonmetallic-sheathed cables enter a box. Each cable has an equipment grounding conductor. The 12 AWG conductors are connected to a receptacle. Two of the 14 AWG conductors are connected to a toggle switch. The other two 14 AWG conductors are spliced together because they serve as a switch loop. The box contains two cable clamps. Calculate the minimum cubic-inch volume required for the box.
30
How high above the finished floor in the living room are switches located?
46 in to center
How high above the garage floor are receptacles located?
46 in to center
How high above the garage floor are switches located?
46 in to center
What is the maximum weight of a luminaire permitted to be hung directly from an outlet box in a ceiling? ______________________ lb.
50 pounds (22.7 kg), unless the box is listed and otherwise marked. See NEC 410.36(A) and 314.27(A)(2).
List the maximum number of 12 AWG conductors permitted in the following metal box: 4 in x 1 1/2 in octagon box
6
List the maximum number of 12 AWG conductors permitted in the following metal box: 3 in x 2 in x 3 1/2 in device box.
8
Table 314.16(A) allows a maximum ten 10 AWG wires in a certain box. However, the box will have two cable clamps and one fixture stud in it. What is the maximum number of 10 AWG wires allowed in this box?
8
What is the code reference on "the purpose of the NEC"?
90.1(A)
According to NEC Article 100 an outlet is:
A point on the wiring system at which current is taken to supply utilization equipment
What code sets standards for electrical installation work?
NEC
What three parties must be satisfied with the completed electrical installation?
Architect, Owner, Inspection Authority
What are junction boxes used for?
As a listed enclosure where two or more cables or raceways are joined and conductors are spliced or connected. to provide the necessary space for making electrical connections, to contain wiring and to support luminaries.
For "Old Work" (remodels), outlet boxes are typically secured to the finished surface by:
Brackets that swing out or snap into place
In a single-family dwelling, how is overcurrent protection for branch circuits required to be provided? See NEC 210.20.
Circuit breakers or fuses
Which list includes notations on the Specification for Electrical Work-Single Family Dwelling found in Appendix A of your EWR book?
Codes, Wiring Method, Permits and Inspection Fees, Workshop, Conductor Size, Dimmers, Luminaries, Service-Entrance Conductors
An offset bar hanger is a device on which boxes are fastened so they can be mounted between joists or studs. The hangers are not adjustable.
False
Branch circuits are rated by their undercurrent protection. See NEC 210.18.
False
Electrical symbols are used to prevent people from doing their own electrical work.
False
GFCI protection is required for receptacles that are not readily accessible and are supplied by a branch circuit dedicated to electric snow-melting, deicing, or pipe line and vessel heating equipment that are installed in accordance with 426.28 or 427.22 as applicable.
False
It is necessary to count luminaire wires when counting the permitted number of conductors in a box according to 314.16.
False
Junction boxes are normally used in wiring the first floor.
False
The Code indicates the rooms in a dwelling that are required to have switched lighting outlets or switched receptacles. Write "yes" (switch required) or "no" (switch not required) for the following areas [see NEC 210.70(A)]: Clothes closet
No
The mounting holes in a device (switch) box are tapped for No. 6-32 screws. The mounting holes in an outlet box are tapped for No. 8-32 screws. The mounting holes in metal boxes for attaching equipment grounding conductors are tapped for ______________________ screws.
No 10-32
How is the rating of the branch-circuit protective device affected when the conductors used are of a larger size than called for by the Code? See NEC 210.18.
No change
Do Underwriters Laboratories and the other recognized testing laboratories "approve" products?
No. Approval is up to the Authority Having Jurisdiction. See NEC 90.4 and 110.2. b. They test the products for conformance to applicable safety standards. When the product passes these tests, the manufacturer of the product is then permitted to affix a "label" (often referred to as a "listing mark") that indicates the product complied with the applicable safety standard when it left their factory
What federal organization dictates requirements for work-related safety issues?
OSHA
What is the wiring method to be used in the workshop?
Section 10 Electrical metallic tubing (EMT), Type NM cable protected in EMT from the joist space to the outlet, etc., or Type MC cable
Match the following switch types with the proper symbol.
Single-pole ---> S Three-way ---> S3 four-way ---> S4 single-pole with pilot light ---> Sp
When wiring a residence, what must be considered when installing wall boxes on both sides of a common partition that separates the garage and a habitable room
The fire-resistance rating of the partition. Local codes may vary. Check this out with the local electrical inspector and/or building official in your community.
The plans show curved lines running between switches and various outlets. What do these lines indicate?
The outlets that are controlled by the switches
Three switches are mounted in a 3-gang switch (device) box. The wall plate for this assembly is called a ____________ plate.
Three-gang, 3-hole switch plate
Why are the lines between outlets that are controlled by switches usually curved?
To distinguish them from building construction drawing lines
A branch circuit is defined in Article 100, Definitions, in the NEC as "The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s)"
True
Calculated load is the result of making calculations per the NEC. Calculations are to be performed in compliance with Article 220. Both Standard and Optional methods are provided. When all loads are taken into consideration and the proper multipliers are applied, the calculated load is the final result. It is necessary for the NEC to provide guidance on how to calculate the various types of loads because the connected load and the calculated load will differ.
True
Junction boxes are normally used to wire exposed portions of the basement?
True
Luminaries are mounted to an outlet box using a luminaire stud or No. 8-32 screws. Mounting hardware (straps, screws, etc.) are furnished with the luminaire. Wall- mounted luminaires that weigh not more than 6 lb. (3 kg) may be secured to a device box using not less than two No. 6-32 screws.
True
Notations are found on the plans next to the specific symbol.
True
Specifications supplements the plans by giving specific information on materials and to help in estimating the costs.
True
Standard sectional switch (device) boxes are mounted by being nailed or screwed to wood backing, mounted to brackets or metal mounting strips (Kruse supports), or mounted to adjustable bar hangers.
True
Does the NEC allow metal raceways to be used with nonmetallic boxes?
Yes
Does the NEC make suggestions about how to wire a house that will be occupied by handicapped persons?
Yes
Is a receptacle required in a bedroom on a 3 ft (900 mm) wall space behind the door? The door is normally left open
Yes
The Code indicates the rooms in a dwelling that are required to have switched lighting outlets or switched receptacles. Write "yes" (switch required) or "no" (switch not required) for the following areas [see NEC 210.70(A)]: bathroom
Yes
The Code indicates the rooms in a dwelling that are required to have switched lighting outlets or switched receptacles. Write "yes" (switch required) or "no" (switch not required) for the following areas [see NEC 210.70(A)]: crawl space (where used for storage)
Yes
The Code indicates the rooms in a dwelling that are required to have switched lighting outlets or switched receptacles. Write "yes" (switch required) or "no" (switch not required) for the following areas [see NEC 210.70(A)]: hallway
Yes
The Code indicates the rooms in a dwelling that are required to have switched lighting outlets or switched receptacles. Write "yes" (switch required) or "no" (switch not required) for the following areas [see NEC 210.70(A)]: stairway
Yes
When a switch (device) box is nailed to a stud, and the nail runs through the box, the nails must not interfere with the wiring space. To accomplish this, keep the nail
a maximum of ¼ in. (6 mm) from the rear of the box
A plan shows in a simple manner, the ________________of outlet, switch, or special electrical device needed
location and type
Does the NEC provide minimum or maximum standards?
minimum
For "Old Work" (remodels), it is common to install cables behind the finished surface by ________ the cable from one access point to another.
fishing
The front edge of a box installed in a combustible wall must be ___________________ with the finished surface.
flush
Although the Code contains many exceptions to the basic overcurrent protection requirements for conductors, in general, the rating of the branch-circuit overcurrent device must ________________ the ampacity of a conductor.
not be more than
Plans use ___________ and ___________ to avoid confusion from too much detail.
notations, specifications
One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved is defined as
qualified person
If a ladder collapses, who is at fault?
the user