SOLUTION AND ANSWER GUIDE
ELECTRICAL WIRING COMMERCIAL
18TH EDITION
CHAPTER 1: COMMERCIAL BUILDING PLANS AND SPECIFICATIONS
REVIEW QUESTION ANSWERS
Note to instructor: It is recommended that students be required to respond, where appropriate,
with answers that are complete sentences.
Refer to the National Electrical Code or the working drawings when necessary. Where
applicable, responses should be written in complete sentences.
1. What section of a commercial building’s specification contains a list of contract
documents?
Answer: A list of the contract documents is contained in General Clauses and
Conditions. A listing of the Commercial Building contract documents is presented in this
chapter under the heading “Commercial Building Plans.” The instructor may wish to
have the students check over this listing and compare it with the plans provided.
2. The requirement for temporary light and power at the job site will be found in what
portion of a commercial building’s specification?
Answer: The Supplementary General Conditions specifies the job site requirements for
temporary light and power. In some contracts, this electrical system becomes the
responsibility of the general contractor; in other contracts, it is the electrical contractor’s
responsibility to install and maintain the temporary electrical system. The instructor may
wish to refer the student to NEC Article 590 and discuss the requirements in detail.
3. The electrician uses the Schedule of Working Drawings for what purpose?
Answer: The electrician uses the Schedule of Working Drawings to determine whether
all of the drawings are at hand. The information on “the other sheets” may be very
important, especially in coordinating with other contractors.
4. Complete the following items by indicating the letter(s) designating the correct source(s)
of information:
No. Answer Item Information
4. Sections Ceiling height Sections, Sheet A6
,No. Answer Item Information
5. Electrical Electrical receptacle Electrical symbol schedule, Chapter 2,
symbol style Figure 2–6
schedule
6. Electrical Electrical outlet Electrical layout drawings, Sheets El,
layout location E2, and E3
drawings
7. Elevations Exterior wall finishes Elevations, Sheets A4 and A5
8. Site plan Grading elevations Site plan, Sheet A4
9. Electrical Panelboard schedules Electrical layout drawings, Sheet E4
layout
drawings
10. Architectural Room width Architectural floor plan, Sheets Al, A2,
floor plan and A3
11. Architectural Swing of door Architectural floor plan, Sheets Al, A2,
floor plan and A3
12. Sections View of interior wall Sections, Sheet A6
Match the items on the left with those on the right by writing the letter designation of the
appropriate organization from the list on the right.
13. NEC Electrical Code National Electrical Code (NEC)
14. IAEI Electrical inspectors International Association of Electrical
Inspectors (IAEI)
15. NFPA Fire codes National Fire Protection Association
(NFPA)
16. IESNA Lighting information Illuminating Engineering Society of
North America (IESNA)
, 17. UL Listing service Underwriters Laboratories, Inc. (UL)
18. NEMA Manufacturers’ National Electrical Manufacturers
standards Association (NEMA)
19. PE Seal Professional Engineer (PE)
Match the items on the left with those on the right by writing the letter designation of the
proper level of NEC interpretation from the list on the right.
20. with special Allowed by the Code Shall be permitted, or Shall not be
permission required, NEC
21. with special May be done Shall be permitted, or Shall not be
permission required, NEC
22. shall Must be done Shall, National Electrical Code
23. shall Required by the Code Shall, National Electrical Code
24. never Up to the electrician Shall be permitted, or Shall not be
required, NEC
25. Find NEC 250.52(A)(5) and record the first four words.
Answer: The first four words of NEC 250.52(A)(5) are Rod and pipe electrodes.
Show required conversion calculations for problem 26 and problem 27.
26. Luminaire style F is four feet long. The length in SI units, as specified by the NEC, is
Answer: The length in SI units is 1.22 m; 4 ft × 0.3048 m/ft = 1.2192 m. As will be
discussed later, this luminaire is now called a 4 by 2 or the equivalent 1200 by 600 in
metric terms. This question assumes that the luminaire is exactly 4 ft long.
27. The gross area of the drugstore basement is 1395 square feet. The area in square meters is
Answer: The area in SI units is 129.7 sq. m; 1395 sq. ft × 0.093 sq. m/sq. ft = 129.7 sq.
m.
To answer Questions 28–31, refer to the Plans included with this book. Determine the
Following dimensions. Write the dimensions using unit names, not symbols (for example, 1
foot, not 1’), and indicate the source of the information.
28. What is the inside clear distance of the interior stairway to the drugstore basement?
, Answer: The inside clear distance of the interior stairway to the Drugstore basement is
4 ft 0 in. (1.22 m), as scaled from Sheet A2.
29. What is the gross square footage of each floor of the building?
Answer: The gross area of each floor of the building is 60 ft × 43 ft = 2580 sq. ft (18.82
m × 13.1 m = 246.5 sq. m), as taken from Sheets Al, A2, and A3.
30. What is the distance in the drugstore from the exterior block wall to the block wall
separating the drugstore from the bakery?
Answer: The distance from the exterior block wall in the Drugstore to the block wall
separating the Drugstore from the Bakery is 21 ft 7 in. (6.58 m), as shown on Sheet A2.
31. What is the finished floor to finished ceiling height on the second floor?
Answer: The finished floor to finished ceiling height on the second floor is 8 ft 6 in.
(2.59 m), as available from East and West Elevations A41–2, and Sheet A6, Cross
Sections A–A and B–B.
For problems 32–34, cite the NEC source. We will show the method of using the NEC Index
for the first two questions in Chapter 1 and will provide this same method of locating
requirements in other chapters of this book.
32. The standard ampere ratings for fuses and fixed trip circuit breakers.
Answer: The standard ampere rating for fuses and fixed trip circuit breakers is given in
NEC Table 240.6(A).
To find this information in the Index of the NEC, locate “Circuit breakers, Article 240, and
locate Rating and under that locate Fixed-Trip circuit breakers, 240.6(A)…” This will
provide the Section number for the ratings.
33. The minimum bending radius for metal-clad cable with a smooth sheath with an external
diameter of 1 in.
Answer: The minimum bending radius for metal clad cable with a smooth sheath with an
external diameter of 1 in. (size 1) is given in NEC 330.24(A)(2) as 12 times the diameter.
To find this information in the Index of the NEC, locate “Metal-clad Cable, Article 330, and
under that locate “Bends, 330.24.” 330.24(A)(2).
34. The permission to use splices in busbars as grounding electrode conductors.
Answer: The permission to use splices in busbars as a grounding electrode conductor is
given in NEC 250.64(C)(2).
ELECTRICAL WIRING COMMERCIAL
18TH EDITION
CHAPTER 1: COMMERCIAL BUILDING PLANS AND SPECIFICATIONS
REVIEW QUESTION ANSWERS
Note to instructor: It is recommended that students be required to respond, where appropriate,
with answers that are complete sentences.
Refer to the National Electrical Code or the working drawings when necessary. Where
applicable, responses should be written in complete sentences.
1. What section of a commercial building’s specification contains a list of contract
documents?
Answer: A list of the contract documents is contained in General Clauses and
Conditions. A listing of the Commercial Building contract documents is presented in this
chapter under the heading “Commercial Building Plans.” The instructor may wish to
have the students check over this listing and compare it with the plans provided.
2. The requirement for temporary light and power at the job site will be found in what
portion of a commercial building’s specification?
Answer: The Supplementary General Conditions specifies the job site requirements for
temporary light and power. In some contracts, this electrical system becomes the
responsibility of the general contractor; in other contracts, it is the electrical contractor’s
responsibility to install and maintain the temporary electrical system. The instructor may
wish to refer the student to NEC Article 590 and discuss the requirements in detail.
3. The electrician uses the Schedule of Working Drawings for what purpose?
Answer: The electrician uses the Schedule of Working Drawings to determine whether
all of the drawings are at hand. The information on “the other sheets” may be very
important, especially in coordinating with other contractors.
4. Complete the following items by indicating the letter(s) designating the correct source(s)
of information:
No. Answer Item Information
4. Sections Ceiling height Sections, Sheet A6
,No. Answer Item Information
5. Electrical Electrical receptacle Electrical symbol schedule, Chapter 2,
symbol style Figure 2–6
schedule
6. Electrical Electrical outlet Electrical layout drawings, Sheets El,
layout location E2, and E3
drawings
7. Elevations Exterior wall finishes Elevations, Sheets A4 and A5
8. Site plan Grading elevations Site plan, Sheet A4
9. Electrical Panelboard schedules Electrical layout drawings, Sheet E4
layout
drawings
10. Architectural Room width Architectural floor plan, Sheets Al, A2,
floor plan and A3
11. Architectural Swing of door Architectural floor plan, Sheets Al, A2,
floor plan and A3
12. Sections View of interior wall Sections, Sheet A6
Match the items on the left with those on the right by writing the letter designation of the
appropriate organization from the list on the right.
13. NEC Electrical Code National Electrical Code (NEC)
14. IAEI Electrical inspectors International Association of Electrical
Inspectors (IAEI)
15. NFPA Fire codes National Fire Protection Association
(NFPA)
16. IESNA Lighting information Illuminating Engineering Society of
North America (IESNA)
, 17. UL Listing service Underwriters Laboratories, Inc. (UL)
18. NEMA Manufacturers’ National Electrical Manufacturers
standards Association (NEMA)
19. PE Seal Professional Engineer (PE)
Match the items on the left with those on the right by writing the letter designation of the
proper level of NEC interpretation from the list on the right.
20. with special Allowed by the Code Shall be permitted, or Shall not be
permission required, NEC
21. with special May be done Shall be permitted, or Shall not be
permission required, NEC
22. shall Must be done Shall, National Electrical Code
23. shall Required by the Code Shall, National Electrical Code
24. never Up to the electrician Shall be permitted, or Shall not be
required, NEC
25. Find NEC 250.52(A)(5) and record the first four words.
Answer: The first four words of NEC 250.52(A)(5) are Rod and pipe electrodes.
Show required conversion calculations for problem 26 and problem 27.
26. Luminaire style F is four feet long. The length in SI units, as specified by the NEC, is
Answer: The length in SI units is 1.22 m; 4 ft × 0.3048 m/ft = 1.2192 m. As will be
discussed later, this luminaire is now called a 4 by 2 or the equivalent 1200 by 600 in
metric terms. This question assumes that the luminaire is exactly 4 ft long.
27. The gross area of the drugstore basement is 1395 square feet. The area in square meters is
Answer: The area in SI units is 129.7 sq. m; 1395 sq. ft × 0.093 sq. m/sq. ft = 129.7 sq.
m.
To answer Questions 28–31, refer to the Plans included with this book. Determine the
Following dimensions. Write the dimensions using unit names, not symbols (for example, 1
foot, not 1’), and indicate the source of the information.
28. What is the inside clear distance of the interior stairway to the drugstore basement?
, Answer: The inside clear distance of the interior stairway to the Drugstore basement is
4 ft 0 in. (1.22 m), as scaled from Sheet A2.
29. What is the gross square footage of each floor of the building?
Answer: The gross area of each floor of the building is 60 ft × 43 ft = 2580 sq. ft (18.82
m × 13.1 m = 246.5 sq. m), as taken from Sheets Al, A2, and A3.
30. What is the distance in the drugstore from the exterior block wall to the block wall
separating the drugstore from the bakery?
Answer: The distance from the exterior block wall in the Drugstore to the block wall
separating the Drugstore from the Bakery is 21 ft 7 in. (6.58 m), as shown on Sheet A2.
31. What is the finished floor to finished ceiling height on the second floor?
Answer: The finished floor to finished ceiling height on the second floor is 8 ft 6 in.
(2.59 m), as available from East and West Elevations A41–2, and Sheet A6, Cross
Sections A–A and B–B.
For problems 32–34, cite the NEC source. We will show the method of using the NEC Index
for the first two questions in Chapter 1 and will provide this same method of locating
requirements in other chapters of this book.
32. The standard ampere ratings for fuses and fixed trip circuit breakers.
Answer: The standard ampere rating for fuses and fixed trip circuit breakers is given in
NEC Table 240.6(A).
To find this information in the Index of the NEC, locate “Circuit breakers, Article 240, and
locate Rating and under that locate Fixed-Trip circuit breakers, 240.6(A)…” This will
provide the Section number for the ratings.
33. The minimum bending radius for metal-clad cable with a smooth sheath with an external
diameter of 1 in.
Answer: The minimum bending radius for metal clad cable with a smooth sheath with an
external diameter of 1 in. (size 1) is given in NEC 330.24(A)(2) as 12 times the diameter.
To find this information in the Index of the NEC, locate “Metal-clad Cable, Article 330, and
under that locate “Bends, 330.24.” 330.24(A)(2).
34. The permission to use splices in busbars as grounding electrode conductors.
Answer: The permission to use splices in busbars as a grounding electrode conductor is
given in NEC 250.64(C)(2).
