Edition by Phil Simmons
All Chapters Covered 1-21| Verified Questions & accurate Solutions
for Exam Preparations| A+ GRADED
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,TABLE OF CONTENTS
• General Requirements for Commercial Wiring
• Branch Circuits
• Calculating Loads
• Feeder and Service Requirements
• Panelboards
• Switchboards and Switchgear
• Overcurrent Protection
• Grounding and Bonding
• Wiring Methods
• Raceways, Boxes, and Fittings
• Wiring Devices
• Lighting Systems
• Motors and Motor Circuits
• Transformers
• Special Occupancies and Special Equipment
• Emergency Systems and Standby Systems
• Hazardous Locations
• Communication Systems
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,Solution and Answer Guide
CHAPTER 1: COMMERCIAL BUILDING PLANS AND SPECIFICATIONS
TABLE OF CONTENTS
Review .......................................................................................................................................................... 1
Note to instructor: It is recommended that students be required to respond, where appropriate,
with answers that are complete sentences.
REVIEW
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.
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, 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.
Q5. What is the primary purpose of the National Electrical Code (NEC) in commercial wiring?
Answer: To safeguard persons and property from electrical hazards by establishing minimum safety standards for
installation.
Q6. Define the term “Authority Having Jurisdiction” (AHJ) in the context of commercial wiring projects.
Answer: AHJ is the local code enforcement agency or inspector responsible for approving electrical installations for
compliance with NEC and local codes.
Q7. What is the minimum working space clearance required in front of electrical equipment rated 600 volts or less?
Answer: At least 3 feet (0.9 m) of clear working space is required, depending on conditions.
Q8. In commercial installations, why must all electrical equipment be “listed” or “labeled”?
Answer: To verify the equipment has been tested and certified for safety by a recognized testing laboratory (e.g., UL
Q9. Give two examples of conditions that may require derating of conductors in commercial wiring.
Answer: (1) Bundling of multiple conductors in a raceway, and (2) high ambient temperatures.
Q10. What is the significance of conductor insulation color coding in commercial wiring?
Answer: It ensures proper identification of grounded, ungrounded (hot), and grounding conductors, reducing wiring
errors and hazards.
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