End of Chapter Review Questions Electrical Wiring Residential 21st Edition by Ray C. Mullin, Phil Si

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Test Bank For Electrical Wiring Industrial 18th Edition Stephen L. Herman, Derrick Atkins Chapter 1-20 Chapter 01: Plans and Sitework 1. New and existing grading levels on a site plan are indicated by _____. a. benchmarks b. contour lines c. building locations d. light standards ANSWER: b POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:26 AM DATE MODIFIED: 5/22/2023 5:27 AM 2. The _____, as given on the site plan, is the reference point from which all elevations are located. a. benchmark b. contour line c. building location d. light standard ANSWER: a POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:27 AM DATE MODIFIED: 5/22/2023 5:29 AM 3. A device used to measure linear distances on building plans is called a(n)_____. a. ruler b. compass c. scale d. indicator ANSWER: c POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:29 AM DATE MODIFIED: 5/22/2023 5:33 AM Copyright Cengage Learning. Powered by Cognero.

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4. On a site plan, the _____indicates the lower edge of the inside of a conduit entering a manhole. a. site plan scale b. manhole range c. invert elevation d. heavy mark line ANSWER: c POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:34 AM DATE MODIFIED: 5/22/2023 5:35 AM 5. Telephone service is provided by a conduit that runs from the telephone pole. The conduit runs underground at a minimum depth of _____ inches. a. 5 b. 6 c. 13 d. 18 ANSWER: d POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:35 AM DATE MODIFIED: 5/22/2023 5:36 AM 6. The drainage hole at the base of a telephone pole is known as a _____ hole. a. weep b. seep c. trickle d. dry ANSWER: a POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:36 AM DATE MODIFIED: 5/22/2023 5:37 AM 7. Although _____ are more expensive to install, they provide many advantages that direct burial installations do not. a. telephone poles b. contoured paths c. pole caps Copyright Cengage Learning. Powered by Cognero.

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d. underground raceways ANSWER: d POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:37 AM DATE MODIFIED: 5/22/2023 5:38 AM 8. Suppose you’re installing an electrical system that will operate at a potential higher than 1000 volts. If you intend to use a rigid nonmetallic conductor such as PVC, which of the following combinations of burial depths and backfill or encasement materials is required by NEC Article 352? a. Installed in not less than 36 inches (900 mm) of earth. b. Installed at a depth of at least 18 inches (460 mm) of concrete. c. Installed at a depth of 24 inches (60 mm) deep and cinder filled. d. Encased in not less than 2 inches (50 mm) of concrete.

ANSWER: d POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:39 AM DATE MODIFIED: 5/22/2023 5:40 AM 9. List the requirements that permit rigid metal conduit to be installed directly in the soil for underground raceways.

ANSWER: Per NEC 300.5 and 300.6, rigid metal conduit can be installed directly in the soil if: • • •

Ferrous conduits (iron or steel) do not rely solely on enamel for corrosion protection; The conduit is made of a material judged suitable for the condition; The conduit is not placed in an excavation that contains large rocks, paving materials, cinders, large or sharply angular substances, or corrosive materials.

POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 5:41 AM DATE MODIFIED: 5/22/2023 5:42 AM 10. The United States is the last major country in the world not using the _____ system as the primary system of measurement. a. English b. metric c. French d. inch-pound Copyright Cengage Learning. Powered by Cognero.

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ANSWER: b POINTS: 1 REFERENCES: Metrics (SI) and the NEC QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:43 AM DATE MODIFIED: 5/22/2023 5:44 AM 11. The NEC commonly expresses units of measure in both the English or pound-inch system and the Metric SI system. A distance of 50 feet is equivalent to _____ in the NEC SI units. a. 150 mm b. 3000 mm c. 15 m d. 3 m ANSWER: c POINTS: 1 REFERENCES: Metrics (SI) and the NEC QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:44 AM DATE MODIFIED: 5/22/2023 5:45 AM 12. Outlet boxes and device boxes use their nominal measurement as their_____ size. a. bench b. knockout c. designated d. trade ANSWER: d POINTS: 1 REFERENCES: Metrics (SI) and the NEC QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:51 AM DATE MODIFIED: 5/22/2023 5:52 AM 13. The metric system is a “base-10” or “_____” system in that values can be easily multiplied or divided by 10 or powers of 10. a. binary b. quaternary c. decimal d. hexadecimal ANSWER: c POINTS: 1 REFERENCES: Metrics (SI) and the NEC Copyright Cengage Learning. Powered by Cognero.

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QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:52 AM DATE MODIFIED: 5/22/2023 5:54 AM 14. In the SI system, what is the prefix corresponding to ten times the base unit? a. deka b. hector c. kilo d. mega ANSWER: a POINTS: 1 REFERENCES: Metrics (SI) and the NEC QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:54 AM DATE MODIFIED: 5/22/2023 5:55 AM 15. How many times larger is a megawatt than a kilowatt? a. 100 b. 1,000 c. 10,000 d. 100,000 ANSWER: b POINTS: 1 REFERENCES: Metrics (SI) and the NEC QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:56 AM DATE MODIFIED: 5/22/2023 5:58 AM 16. Devices called scales are frequently used to make measurements of building plans. There are two basic types of scales: _____ and _____. a. electrician, engineer b. architect, industrial c. architect, electrician d. architect, engineer ANSWER: d POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 5:59 AM DATE MODIFIED: 5/22/2023 6:00 AM Copyright Cengage Learning. Powered by Cognero.

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17. Traditional scales generally permit six different scales on one measuring device. An alternative plan measurement device that contains 72 different scale values is known as the _____ scale. a. roller b. triangular c. architect d. engineer ANSWER: a POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:00 AM DATE MODIFIED: 5/22/2023 6:02 AM 18. Suppose you’re measuring the length of a building shown on a site plan drawn to a scale of 1” = 50’. A building length measurement on the plan of 2.0” indicates an actual building length of ____ feet. a. 25 b. 50 c. 100 d. 200 ANSWER: c POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:04 AM DATE MODIFIED: 5/22/2023 6:05 AM 19. Suppose you’re verifying the invert elevation of a proposed manhole on a site plan. The site plan is drawn to a scale of 1” = 10’. Using the site plan, you measure 0.5” between grade elevation and the level of the lower edge of the inside of the conduit entering the manhole. Which of the following best represents your measured invert elevation in feet? a. 5 b. 2.5 c. 10 d. 7.5 ANSWER: a POINTS: 1 REFERENCES: Explanation of Plan Symbols QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:05 AM DATE MODIFIED: 5/22/2023 6:06 AM 20. In a lighting standard, the NEC requires that all conductive parts, including the grounding electrode, base, bolts, and conduits, be _____ together to achieve comprehensive grounding and bonding.

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a. connected b. fastened c. bonded d. wired ANSWER: c POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:07 AM DATE MODIFIED: 5/22/2023 6:08 AM 21. True or False: Section 250.54 of the NEC states that the earth provides an effective ground-fault current path. a. True b. False ANSWER: False POINTS: 1 REFERENCES: Testing the Site for Grounding Requirements QUESTION TYPE: True / False HAS VARIABLES: False DATE CREATED: 5/22/2023 6:08 AM DATE MODIFIED: 5/22/2023 6:09 AM 22. Discuss how to determine the location of the building using the site plan.

ANSWER: The building location is given on the site plan by referring to existing points such as the centerline of a street. If the electrical contractor and the crew arrive on the site before the general contractor arrives, they are not required to “stake out” (locate) the building.

However, they should be able to determine its approximate location. A site plan shows the property lines and the centerlines of the street from which the electrician can locate the building and other site improvements.

POINTS: 1 REFERENCES: Construction Plans QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:10 AM DATE MODIFIED: 5/22/2023 6:10 AM 23. What precautions should be taken if a direct buried cable is used?

ANSWER: If the direct buried cable is used, care must be taken to protect the cable from damage. For example, the cable could be installed in the ground to a greater depth than that at which normal digging takes place. Added protection is obtained by placing a treated board over the cable to provide a shield against digging and probing near the cable. The cable should also be surrounded by a layer of sand to prevent any abrasion of the cable by sharp stones and other objects in the soil.

POINTS: 1 Copyright Cengage Learning. Powered by Cognero.

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REFERENCES: Interpreting the Site Plan QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:11 AM DATE MODIFIED: 5/22/2023 6:11 AM 24. Describe the differences in how the US and SI systems express numbers with many digits. Next, write the US numbers 12,345.678999 and 1,234.5678 in the notation appropriate for the SI system.

ANSWER: In the United States, it is the practice to use a period as the decimal marker and a comma to separate a string of numbers into groups of three for easier reading. In many countries, the comma has been used in lieu of the decimal marker, and spaces are left to separate a string of numbers into groups of three. The SI system, taking something from both, uses the period as the decimal marker and the space to separate a string of numbers into groups of three, starting from the decimal point and counting in either direction. Using this definition, the US number 12,345.678999 would be expressed as 12 345.678 999 in the SI system. An exception to this is when there are four numbers on either side of the decimal point. In this case, the third and fourth numbers from the decimal point are not separated. Using this definition, the US number 1,234.5678 would be expressed as 1234.5678 in the SI system.

POINTS: 1 REFERENCES: Metrics (SI) and the NEC QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:12 AM DATE MODIFIED: 5/26/2023 3:14 AM 25. The Wenner four-point test and the fall-of-potential test are both used for determining the resistivity of grounding systems. Explain the difference between the purpose of each test in the design and functional verification of grounding systems.

ANSWER: The Wenner four-point test is generally performed before construction begins and measures the ground resistance over a wide area. Test results are used to design a properly functioning grounding system. The fall-of-potential test measures the grounding resistance of an alreadyinstalled grounding system and should be performed annually to detect degradation of the system before equipment and performance problems occur.

POINTS: 1 REFERENCES: Testing the Site for Grounding Requirements QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:13 AM DATE MODIFIED: 5/22/2023 6:14 AM 26. Both the fall-of-potential test and the clamp-on ground resistance test can be used to evaluate the performance of installed grounding systems. List the advantages of the clamp-on ground resistance test over the fall-of-potential test for annual grounding system performance.

ANSWER: The clamp-on ground resistance test has the following four advantages over the three-point fall-of-potential test: Copyright Cengage Learning. Powered by Cognero.

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The service grounding system does not have to be disconnected and isolated from the neutral bus.

There are no probes that have to be driven into the ground or long connecting conductors.

The neutral conductor supplied by the utility company ties innumerable grounds together in parallel. The clamp-on ground tester measures the effective resistance of the entire grounding system.

Because this test is performed by clamp-on meter, there are no connections that have to be broken or reconnected, resulting in a safer procedure.

POINTS: 1 REFERENCES: Testing the Site for Grounding Requirements QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:14 AM DATE MODIFIED: 5/22/2023 6:15 AM 27. Discuss grounding as it relates to lighting standards.

ANSWER: It is important that proper grounding be achieved at each lighting standard. An equipment grounding conductor shall be installed with the supply conductors, as earth cannot be the sole grounding path; see NEC 250.54. This section of the National Electric Code also permits the installation of supplementary grounding electrodes. It is mandatory that all conductive parts, including the grounding electrode, base, bolts, and conduits be bonded together to achieve comprehensive grounding and bonding, see NEC 250.4, 250.134, and 250.54.

POINTS: 1 REFERENCES: Interpreting the Site Plan QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:15 AM DATE MODIFIED: 5/22/2023 6:16 AM

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Chapter 02: The Unit Substation 1. The step-down transformers, metering, and switching equipment necessary to supply the low-voltage loads to the customer are housed in a _____. a. unit substation b. grounding bus c. terminal d. secondary bus ANSWER: a POINTS: 1 REFERENCES: Introduction QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:06 AM DATE MODIFIED: 5/22/2023 9:07 AM 2. After the incoming voltage is reduced to the desired value, it is taken by _____ into the low-voltage section. a. busbars b. grounding buses c. terminals d. secondary buses ANSWER: a POINTS: 1 REFERENCES: The Low-Voltage Section QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:08 AM DATE MODIFIED: 5/22/2023 9:08 AM 3. A device called a _____ provides a reliable method of terminating a high-voltage cable. a. lighting arrester b. pothead c. grounding bus d. secondary bus ANSWER: b POINTS: 1 REFERENCES: The High-Voltage Section QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:09 AM DATE MODIFIED: 5/22/2023 9:09 AM 4. Lightning arresters are designed to provide a(n) _____ path to ground for any surge currents such as those resulting from a lightning strike. a. high impedance Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation b. low-impedance c. indirect d. intermittent ANSWER: b POINTS: 1 REFERENCES: The High-Voltage Section QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:09 AM DATE MODIFIED: 5/22/2023 9:10 AM 5. The process of selecting protective devices so that there is a minimum power interruption in case of a fault or overload is known as _____. a. transformation b. masking c. coordination d. correlation ANSWER: d POINTS: 1 REFERENCES: Determining Transformer Fuse Size QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:10 AM DATE MODIFIED: 5/22/2023 9:11 AM 6. If the primary current is less than two amperes for a transformer rated at 1000 volts or less, the short-circuit protective device can be set at not more than _____ percent of this value. a. 100 b. 200 c. 300 d. 400 ANSWER: c POINTS: 1 REFERENCES: Determining Transformer Fuse Size QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:12 AM DATE MODIFIED: 5/22/2023 9:13 AM 7. High-voltage fuses are available with either an N or a(n) _____ rating. a. B b. C c. D Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation d. E ANSWER: d POINTS: 1 REFERENCES: The High-Voltage Section QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:13 AM DATE MODIFIED: 5/22/2023 9:14 AM 8. A 600-volt to 200-volt transformer would become a 600-volt to _____-volt transformer if the connections were reversed. a. 100 b. 300 c. 1200 d. 1800 ANSWER: d POINTS: 1 REFERENCES: Overcurrent Protection QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:14 AM DATE MODIFIED: 5/22/2023 9:15 AM 9. The _____ of a transformer is the winding that is connected to a voltage source. a. ammeter b. secondary c. primary d. short circuit ANSWER: c POINTS: 1 REFERENCES: Overcurrent Protection QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:15 AM DATE MODIFIED: 5/22/2023 9:16 AM 10. An alternative to grounding the secondary is to let it _____ ; that is, the secondary remains ungrounded. a. sink b. float c. surface d. exit ANSWER: b POINTS: 1 Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation REFERENCES: The Low-Voltage Section QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:16 AM DATE MODIFIED: 5/22/2023 9:17 AM 11. Rate reductions are made by the power company when the metering measurements are taken on the _____ side of the transformer. a. high-voltage b. variable-voltage c. low-voltage d. secondary bus ANSWER: a POINTS: 1 REFERENCES: The High-Voltage Metering Equipment QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:17 AM DATE MODIFIED: 5/22/2023 9:18 AM 12. The rates charged by the power company for the energy used are based on the readings of the meter registers and the _____ indicators. a. maximum demand b. short circuit c. terminal d. ampere ANSWER: a POINTS: 1 REFERENCES: The High-Voltage Metering Equipment QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:19 AM DATE MODIFIED: 5/31/2023 12:18 AM 13. The autotransformer is designed to provide voltage components to the potential coils of the reactive meter. These voltage components are _____ degrees out of phase with the line voltage. a. 45 b. 90 c. 180 d. 270 ANSWER: b POINTS: 1 REFERENCES: The High-Voltage Metering Equipment Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:20 AM DATE MODIFIED: 5/22/2023 9:20 AM 14. Connections between the current and potential transformers in the high-voltage section of the unit substation and the autotransformer and meter sockets in the cabinet are made with size 12 _____ wire. a. Music Wire Gauge b. US Steel Wire Gauge c. W&M Wire Gauge d. American Wire Gauge ANSWER: d POINTS: 1 REFERENCES: The High-Voltage Metering Equipment QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:21 AM DATE MODIFIED: 5/22/2023 9:22 AM 15. The decimal impedance in a transformer is found by determining the ratio of the variable source voltage which provides the rated full-load current of the secondary to the rated voltage of the _____ winding. a. high-voltage b. variable-voltage c. low-voltage d. short circuit ANSWER: a POINTS: 1 REFERENCES: Overcurrent Protection QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:22 AM DATE MODIFIED: 5/22/2023 9:23 AM 16. Suppose you have a wye-connected three-phase power source. If the phase voltage is 240 V, what is the line voltage? a. 416 V b. 120 V c. 240 V d. 139 V ANSWER: a POINTS: 1 REFERENCES: Introduction QUESTION TYPE: Multiple Choice HAS VARIABLES: False Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation DATE CREATED: 5/22/2023 9:23 AM DATE MODIFIED: 5/22/2023 9:23 AM 17. Suppose you’re sizing transformers configured in an open delta connection with ground. The application requires 20 kVA of single-phase load and 15 kVA of three-phase load. The transformer supplying the single-phase load must provide _____ VA. a. 28,661 b. 20,000 c. 15,000 d. 17,321 ANSWER: a POINTS: 1 REFERENCES: Service Entrances QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:24 AM DATE MODIFIED: 5/22/2023 9:24 AM 18. Most three-phase transformer connections have a delta connection as either the primary or secondary. The delta connection _____ the voltage in the event of an unbalanced condition. a. increases b. decreases c. grounds d. stabilizes ANSWER: d POINTS: 1 REFERENCES: Service Entrances, Page 41 QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:24 AM DATE MODIFIED: 5/22/2023 9:25 AM 19. An open delta connection can supply _____ % of the total capacity of the two transformers. a. 96.4% b. 54.5% c. 78.8% d. 86.6% ANSWER: d POINTS: 1 REFERENCES: Service Entrances QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:25 AM Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation DATE MODIFIED: 5/22/2023 9:26 AM 20. Wye-wye connections are seldom used because they can exhibit _____ voltages between phases if line currents become unstable. a. high b. low c. unstable d. constant ANSWER: c POINTS: 1 REFERENCES: Service Entrances QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:26 AM DATE MODIFIED: 5/22/2023 9:27 AM 21. What is the procedure for terminating an incoming high-voltage cable?

ANSWER: To connect the incoming lead-covered cable at the pothead, the cable is opened and the conductors are bared for several inches. The wiping sleeve of the pothead is cut off until the opening is the correct size to receive the cable. The cable is then inserted until the lead sheath is inside the sleeve. The following steps are then completed in the order given: (1) the cable conductors are connected to the terminals at the end of the porcelain insulators; (2) the lead cable is wiped (soldered) to the wiping sleeve; and (3) the pothead is filled with a protective and insulating compound (usually made from an asphalt or resin base).

POINTS: 1 REFERENCES: The High-Voltage Section QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:27 AM DATE MODIFIED: 5/22/2023 9:28 AM 22. What should you be wary of when coordinating high-voltage fusing?

ANSWER: Coordination is the process of selecting protective devices so that there is minimal power interruption in case of a fault or overload. For any particular situation, a high-voltage fuse value should be selected to ensure that other protective devices between it and the loads can react to a given condition in less time. Fuse selection for coordination is covered in NEC Article 100 Coordination, Selective. Problems in the coordination of high-voltage fusing occur most frequently when: • Circuit breakers are used as secondary protective devices • A single main protective device is installed on the secondary side of the transformer POINTS: 1 REFERENCES: Determining Transformer Fuse Size QUESTION TYPE: Essay HAS VARIABLES: False Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:28 AM DATE MODIFIED: 5/22/2023 9:29 AM 23. How do you select a fuse with the correct continuous current rating to provide transformer protection?

ANSWER: The selection of the fuse with the correct continuous current rating to provide transformer protection is based on the following recommendations: • Select a fuse with the lowest rating that has a minimum melting time of 0.1 seconds at 12 times the continuous current rating of the transformer.

• Select a fuse with a continuous current rating of 1.6 times the continuous current rating of the transformer.

• Select a fuse that complies with NEC Article 450.

POINTS: 1 REFERENCES: The High-Voltage Section (Continuous Current Ratings) QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:29 AM DATE MODIFIED: 5/22/2023 9:30 AM 24. What role do taps play?

ANSWER: Although voltage systems are generally classified by a voltage value, such as a 2300-volt or a 4160-volt system, this exact value is rarely the voltage provided at the transformer. To compensate for this probable voltage difference, taps are built into the transformer. These taps are usually provided at 2 1⁄2-percent increments above and below the standard rated voltage. For example, taps on a 4160/480-volt transformer may provide for voltages of 3952, 4056, 4160, 4264, and 4368 volts. Connections at the proper voltage levels will provide the desired 480 volts on the secondary.

POINTS: 1 REFERENCES: The Transformer Section QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:30 AM DATE MODIFIED: 5/22/2023 9:31 AM 25. Discuss the role and location of the grounding bus.

ANSWER: The majority of the connections to ground are made in the low-voltage section. However, the electrician should be aware that a grounding bus usually runs the entire length of the unit substation. The bus provides the means for a positive ground and bond connection between the compartments, as well as a convenient place to make other grounding and bonding connections. Two types of grounding connections are of special interest. The system grounding connection is used to connect a phase or the neutral of the transformer secondary to ground. This connection is made by the use of a main or system bond jumper, sized in accordance with NEC 250.28 and Table 250.102(C)(1), and a grounding electrode sized according to NEC 250.66 and Table 250.66. The secondary grounding and bonding connections of special interest are the connections of all the incoming metal raceways to the Copyright Cengage Learning. Powered by Cognero.

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Chapter 02: The Unit Substation grounding system. When a raceway enters through the base of the unit substation, a bonding and grounding connection must be installed between the conduit and the grounding system.

Conductors used secondary bonding and grounding are sized according to NEC 250.122 and Table 250.122.

POINTS: 1 REFERENCES: The Low-Voltage Section QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:31 AM DATE MODIFIED: 5/22/2023 9:32 AM 26. Discuss why high-voltage metering equipment includes both a watt-hour meter and a VAR-meter and how power factor impacts industrial power rates.

ANSWER: The relative readings of the VAR-meter and watt-hour meter can be used to calculate the power factor. The higher the ratio of the VAR-meter reading to watt-hour meter reading, the lower the power factor. Some power companies charge a penalty if the power factor falls below a certain level.

POINTS: 1 REFERENCES: The High-Voltage Metering Equipment, Page 39-40.

QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:32 AM DATE MODIFIED: 5/22/2023 9:33 AM 27. Describe the relationship between line current and line voltage versus phase current and phase voltage in wye and delta three-phase system connections.

ANSWER: In a wye connection, the line voltage is greater than the phase voltage by a factor of the square root of 3; the line current and phase current are the same. In a delta connection, the line voltage and phase voltage are the same; the line current is greater than the phase current by a factor of the square root of 3.

POINTS: 1 REFERENCES: Introduction QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 9:33 AM DATE MODIFIED: 5/22/2023 9:33 AM

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Chapter 03: Feeder Bus System 1. Busways with three-conductor systems frequently contain _____ busbars connected in pairs. a. three b. six c. twelve d. twenty-four ANSWER: b POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:18 AM DATE MODIFIED: 5/22/2023 6:19 AM 2. Straight sections, elbows, tees, and _____ are standard components available for use so that ducts can be installed horizontally or vertically, edgewise, or flat, and can meet any turn or elevation requirement. a. busbars b. covers c. casings d. crosses ANSWER: d POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:20 AM DATE MODIFIED: 5/22/2023 6:21 AM 3. For feeder busway No. 2, rated at 1600 amperes, what is the current density in busbars with cross-sectional area of 394 square millimeters? a. 1 ampere/mm2 b. 2 ampere/mm2 c. 3 ampere/mm2 d. 4 ampere/mm2 ANSWER: b POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:21 AM DATE MODIFIED: 5/22/2023 6:25 AM 4. The plug-in busway is much like a _____ extending through a complete load area.

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Chapter 03: Feeder Bus System a. switchboard b. busbar c. panelboard d. circuit breaker ANSWER: c POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:35 AM DATE MODIFIED: 5/22/2023 6:36 AM 5. Power can be tapped from the feeder busway at any _____ opening. a. joint b. handhole c. enclosure d. tap ANSWER: b POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:36 AM DATE MODIFIED: 5/22/2023 6:37 AM 6. Tap-off openings every _____ inches along the plug-in busway mean that there is always a convenient location to connect a machine. a. four b. five c. nine d. ten ANSWER: d POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:37 AM DATE MODIFIED: 5/22/2023 6:38 AM 7. The plug-in unit size of a bus plug is based on the _____. a. switch ampere rating b. protective devices rating c. number of bus plugs required Copyright Cengage Learning. Powered by Cognero.

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Chapter 03: Feeder Bus System d. number of end-connections ANSWER: a POINTS: 1 REFERENCES: Bus Plugs QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:38 AM DATE MODIFIED: 5/22/2023 6:39 AM 8. What is the common name used by electricians for the assembly properly known as a busway? a. bus duct b. busbar c. panelboard d. switchboard ANSWER: a POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:41 AM DATE MODIFIED: 5/22/2023 6:41 AM 9. Feeder busway sections are available in standard _____ -ft lengths and in other lengths on special order. a. 5 b. 10 c. 15 d. 20 ANSWER: b POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:42 AM DATE MODIFIED: 5/22/2023 6:42 AM 10. The connection of the busway to enclosures such as unit substations is accomplished with _____. a. ventilated steel halves b. copper busbar c. flanged end connections d. No. 1 connections ANSWER: c POINTS: 1 REFERENCES: Feeder Ducts Copyright Cengage Learning. Powered by Cognero.

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Chapter 03: Feeder Bus System QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:43 AM DATE MODIFIED: 5/22/2023 6:44 AM 11. The electrical contact surfaces of busbars at connection points are coated with _____ in order to reduce pitting (corrosion). a. copper b. steel c. aluminum d. silver ANSWER: d POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:44 AM DATE MODIFIED: 5/22/2023 6:45 AM 12. In the feeder busway in No. 2, ____ Snap-On covers insulate the bolted busbar sections. a. polycarbonate b. vinyl plastic c. stainless steel d. copper ANSWER: b POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:45 AM DATE MODIFIED: 5/22/2023 6:46 AM 13. Connecting busway housing includes a scarf-lap feature which permits two adjacent duct sections to overlap each other by _____in, thereby providing high rigidity and strength to the assembly. a. 12 b. 6 c. 3 d. 9 ANSWER: a POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False Copyright Cengage Learning. Powered by Cognero.

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Chapter 03: Feeder Bus System DATE CREATED: 5/22/2023 6:46 AM DATE MODIFIED: 5/22/2023 6:47 AM 14. The bus plugs provide branch-circuit protection for _____ of the machines and must be selected according to the specific requirements of the individual machines. a. some b. many c. most d. each ANSWER: d POINTS: 1 REFERENCES: Bus Plugs QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:47 AM DATE MODIFIED: 5/22/2023 6:48 AM 15. Connections between the No. 2 feeder busway and the 225-ampere plug-in busway runs are made using _____ cubicles. a. Circuit-breaker b. Plug-in c. Flanged end d. End-closer ANSWER: a POINTS: 1 REFERENCES: The Circuit-Breaker Cubicles QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:49 AM DATE MODIFIED: 5/22/2023 6:49 AM 16. The busbars in the busway are coated with _____ at each connection point as it is unequaled as an electrical conductor. a. aluminum b. copper c. gold d. silver ANSWER: d POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:50 AM Copyright Cengage Learning. Powered by Cognero.

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Chapter 03: Feeder Bus System DATE MODIFIED: 5/22/2023 6:51 AM 17. Branch-circuit protection for each of the machines in a plant manufacturing area is provided by _____. a. steel halves b. bus plugs c. end connections d. machine tools ANSWER: b POINTS: 1 REFERENCES: Bus Plugs QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:51 AM DATE MODIFIED: 5/22/2023 6:52 AM 18. Busways held up by cables must all be supported at intervals of _____ft or less. a. three b. four c. five d. six ANSWER: c POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:52 AM DATE MODIFIED: 5/22/2023 6:53 AM 19. The use of _____ clamp hangers eliminates the drilling, cutting, and bending generally associated with hangers constructed on the job. a. prefabricated b. stenciled c. metal d. plastic ANSWER: a POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 6:53 AM DATE MODIFIED: 5/22/2023 6:54 AM 20. Discuss the advantages of a plug-in busway over a panelboard for supplying machines on a large production floor.

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Chapter 03: Feeder Bus System ANSWER:

The busway system is much more flexible. If a machine is to be moved from one location to another, it is a simple matter to unplug the circuit-protective device, move it and the machine to the new location, and plug the protective device back into the busway system.

POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:55 AM DATE MODIFIED: 5/22/2023 6:55 AM 21. Describe the circuit-breaker cubicle.

ANSWER: The circuit-breaker cubicle consists of a cube-shaped steel housing. This housing can be attached to the lower side of the ventilated feeder duct. Two 225-ampere circuit breakers are provided in a single housing. Openings in the sides of the cubicle permit the attachment of a plug-in busway. Feeders protected by the circuit breaker run in opposite directions at right angles to the feeder. The circuit breakers protect the plug-in duct from overloads as required by 368.17( C). This section of the Code requires that the means for disconnecting can be operated from the floor.

POINTS: 1 REFERENCES: The Circuit-Breaker Cubicles QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:56 AM DATE MODIFIED: 5/22/2023 6:56 AM 22. What are the possible structures (styles) of plug-in busway fittings?

ANSWER: Plug-in busway fittings include: edgewise elbows, flatwise elbows, right-hand edgewise tee, right-hand flatwise tee, left-hand edgewise tee, left-hand flatwise tee, edgewise cross, and flatwise cross.

POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:57 AM DATE MODIFIED: 5/22/2023 6:57 AM 23. How are bus plugs selected?

ANSWER: The bus plugs provide branch-circuit protection for each of the machines and must be selected according to the specific requirements of the individual machines. One advantage of the fusible plug-in unit is that a minimum number of sizes are needed. The plug-in unit size is based on the switch ampere rating. In addition, the protective device rating can be easily changed. Where such devices are located out of reach of machine operators, suitable means must be provided for operating the disconnect means. See NEC 368.17 ( C).

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Chapter 03: Feeder Bus System POINTS: 1 REFERENCES: Bus Plugs QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:57 AM DATE MODIFIED: 5/22/2023 6:58 AM 24. How are plug-in busways suspended?

ANSWER: There is an almost unlimited selection of methods for hanging or supporting the plug-in busway. Common support arrangements are built around the use of clamp hangers.

Prefabricated clamp hangers eliminate the drilling, cutting, or bending generally associated with hangers constructed on the job. Clamp hanger halves are slipped over the duct casing and bolted together. Specific support arrangements include bracket supports, strap hangers, rod hangers, and messenger cable suspension.

POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 6:59 AM DATE MODIFIED: 5/22/2023 7:00 AM 25. Describe how connecting busways to enclosures such as unit substations can reduce the impedance of the total busway length?

ANSWER: The connection of the busway to enclosures such as unit substations is accomplished with flanged end connections. In addition, these connections are used to transpose the positions of the buses connected to the same phase. This transposition reduces the impedance of the total length of the busway. Because each phase is located at two places (or more in larger busways), the effects of the magnetic field are reduced, and the opposition to the current flow is also reduced. See 300.20 in the NEC for installation requirements related to induced currents.

POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:00 AM DATE MODIFIED: 5/22/2023 7:01 AM 26. Given that the standard conductor current density is 1.55 amperes per square millimeters, what is the maximum current that could be supplied by a bus bar measuring 8 by 60 mm.

ANSWER: Start by calculating the cross-sectional area of the bus in square millimeters: bus cross sectional area = (8 mm)(60 mm) = 480 mm2 Next, calculate the maximum current using the standard conductor current density and calculated bus cross-sectional area.

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Chapter 03: Feeder Bus System max current = (1.55

) x (480 mm2) = 744 A

POINTS: 1 REFERENCES: Feeder Ducts QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:01 AM DATE MODIFIED: 5/22/2023 7:07 AM 27. Discuss the advantages of a plug-in busway over a panelboard for supplying machines on a large production floor.

ANSWER: The busway system is much more flexible. If a machine is to be moved from one location to another, it is a simple matter to unplug the circuit-protective device, move it and the machine to the new location, and plug the protective device back into the busway system.

POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:07 AM DATE MODIFIED: 5/22/2023 7:08 AM 28. Describe the circuit-breaker cubicle.

ANSWER: The circuit-breaker cubicle consists of a cube-shaped steel housing. This housing can be attached to the lower side of the ventilated feeder duct. Two 225-ampere circuit breakers are provided in a single housing. Openings in the sides of the cubicle permit the attachment of a plug-in busway. Feeders protected by the circuit breaker run in opposite directions at right angles to the feeder. The circuit breakers protect the plug-in duct from overloads as required by 368.17( C). This section of the Code requires that the means for disconnecting can be operated from the floor.

POINTS: 1 REFERENCES: The Circuit-Breaker Cubicles QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:08 AM DATE MODIFIED: 5/22/2023 7:09 AM 29. What are the possible structures (styles) of plug-in busway fittings?

ANSWER: Plug-in busway fittings include: edgewise elbows, flatwise elbows, right-hand edgewise tee, right-hand flatwise tee, left-hand edgewise tee, left-hand flatwise tee, edgewise cross, and flatwise cross.

POINTS: 1 REFERENCES: Plug-In Busway Copyright Cengage Learning. Powered by Cognero.

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Chapter 03: Feeder Bus System QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:11 AM DATE MODIFIED: 5/22/2023 7:12 AM 30. How are bus plugs selected?

ANSWER: The bus plugs provide branch-circuit protection for each of the machines and must be selected according to the specific requirements of the individual machines. One advantage of the fusible plug-in unit is that a minimum number of sizes are needed. The plug-in unit size is based on the switch ampere rating. In addition, the protective device rating can be easily changed. Where such devices are located out of reach of machine operators, suitable means must be provided for operating the disconnect means. See NEC 368.17 ( C).

POINTS: 1 REFERENCES: Bus Plugs QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:12 AM DATE MODIFIED: 5/22/2023 7:13 AM 31. How are plug-in busways suspended?

ANSWER: There is an almost unlimited selection of methods for hanging or supporting the plug-in busway. Common support arrangements are built around the use of clamp hangers.

Prefabricated clamp hangers eliminate the drilling, cutting, or bending generally associated with hangers constructed on the job. Clamp hanger halves are slipped over the duct casing and bolted together. Specific support arrangements include bracket supports, strap hangers, rod hangers, and messenger cable suspension.

POINTS: 1 REFERENCES: Plug-In Busway QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 7:13 AM DATE MODIFIED: 5/22/2023 7:14 AM

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Chapter 04: Panelboards 1. According to the NEC, part of the definition of a panelboard includes a single panel or group of panel units designed for assembly in the form of a single panel including _____ and automatic overcurrent devices. a. fuses b. circuit breakers c. cables d. buses ANSWER: d POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:48 AM DATE MODIFIED: 5/22/2023 9:50 AM 2. Panelboards are typically either single-phase or three-phase and are used to distribute _____ throughout a facility. a. voltage b. current c. power d. resistance ANSWER: c POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:50 AM DATE MODIFIED: 5/22/2023 9:51 AM 3. Panelboards are available with standard main ratings of 100, 225, 400, 600, 800, and _____ amperes. a. 900 b. 1000 c. 1100 d. 1200 ANSWER: d POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:52 AM DATE MODIFIED: 5/22/2023 9:53 AM 4. The temperature rating of conductors must be selected and coordinated after consideration of the _____ of any connected termination, conductor, or device. a. lowest temperature rating Copyright Cengage Learning. Powered by Cognero.

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Chapter 04: Panelboards b. highest temperature rating c. average temperature rating d. maximum amperage rating ANSWER: a POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:53 AM DATE MODIFIED: 5/22/2023 9:54 AM 5. Circuit control and _____ protection must be provided for all circuits and the power-consuming devices connected to these circuits. a. lighting b. appliance c. busway d. overcurrent ANSWER: d POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:54 AM DATE MODIFIED: 5/22/2023 9:55 AM 6. The trip rating of the circuit breaker cannot exceed the ampacity of the _____ in the panelboard. a. fuses b. appliances c. switches d. busbars ANSWER: d POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:55 AM DATE MODIFIED: 5/22/2023 9:56 AM 7. It is common practice to have the total amperage of the branch-circuit _____ exceed the rating of the main breaker by several times. a. fuses b. buses c. connectors Copyright Cengage Learning. Powered by Cognero.

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Chapter 04: Panelboards d. breakers ANSWER: d POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:56 AM DATE MODIFIED: 5/31/2023 12:50 AM 8. Two single-pole breakers require installation space _____ that of a double-pole breaker. a. one-quarter of b. one-half of c. equal to d. three-quarter of ANSWER: c POINTS: 1 REFERENCES: Branch-Circuit Protective Devices QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:57 AM DATE MODIFIED: 5/22/2023 9:58 AM 9. According to NEC 240.15, two-pole breakers can be used to supply line-to-line loads such as a 208-volt single-phase load or _____multiwire branch circuits with two ungrounded conductors and a neutral for two, 120-volt single-phase circuits. a. two-wire b. three-wire c. six-wire d. four-wire ANSWER: b POINTS: 1 REFERENCES: Branch-Circuit Protective Devices QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:58 AM DATE MODIFIED: 5/22/2023 9:58 AM 10. For a three-pole circuit breaker, _____ pole(s) is (are) required for each breaker used. a. one b. two c. three d. four ANSWER: c Copyright Cengage Learning. Powered by Cognero.

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Chapter 04: Panelboards POINTS: 1 REFERENCES: Branch-Circuit Protective Devices QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:59 AM DATE MODIFIED: 5/22/2023 9:59 AM 11. Three-pole breakers can be used to supply line-to-line loads such as a 480-volt three-phase load like a motor or a _____ multiwire branch circuit with three ungrounded and a neutral. a. two-wire b. three-wire c. six-wire d. four-wire ANSWER: d POINTS: 1 REFERENCES: Branch-Circuit Protective Devices QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 9:59 AM DATE MODIFIED: 5/22/2023 10:00 AM 12. When panelboards are purchased, the interiors are specified by the total number of _____ required. a. fuses b. buses c. poles d. circuit breakers ANSWER: c POINTS: 1 REFERENCES: Branch-Circuit Protective Devices QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:00 AM DATE MODIFIED: 5/31/2023 12:52 AM 13. The main for a panelboard may be either a(n) _____ or a circuit breaker. a. fuse b. appliance c. busbar d. pole ANSWER: a POINTS: 1 REFERENCES: Panelboard Protective Devices QUESTION TYPE: Multiple Choice Copyright Cengage Learning. Powered by Cognero.

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Chapter 04: Panelboards HAS VARIABLES: False DATE CREATED: 5/22/2023 10:39 AM DATE MODIFIED: 5/22/2023 10:40 AM 14. In general, in a circuit breaker, a low setting may be _____ times the overload rating. a. two to four b. six to eight c. ten to twelve d. fourteen to sixteen ANSWER: c POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:40 AM DATE MODIFIED: 5/22/2023 10:41 AM 15. Adjustment of the _____ determines the degree of protection provided by the circuit breaker if a short circuit occurs. a. magnetic trip b. double pole c. triple pole d. single pole ANSWER: a POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:41 AM DATE MODIFIED: 5/22/2023 10:42 AM 16. The voltage ratings of the breakers must be higher than that of the system. Breakers are usually rated at 250 or _____ volts. a. 300 b. 400 c. 500 d. 600 ANSWER: d POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:43 AM DATE MODIFIED: 5/22/2023 10:43 AM Copyright Cengage Learning. Powered by Cognero.

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Chapter 04: Panelboards 17. If there is any question as to the exact value of the available fault current at any point, a circuit breaker or fuse with a _____ interrupting rating is required to be installed. a. zero b. low c. medium d. high ANSWER: d POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:44 AM DATE MODIFIED: 5/22/2023 10:44 AM 18. In order to ensure that feeder lug connections are properly tightened, manufacturers provide _____ specifications to be used when installing connectors. a. resistance b. current c. torque d. voltage ANSWER: c POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:44 AM DATE MODIFIED: 5/22/2023 10:45 AM 19. If taps are made to a feeder, they may be _____ in size according to NEC 240.21(B). a. expanded b. adjusted c. reduced d. scaled ANSWER: c POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:45 AM DATE MODIFIED: 5/22/2023 10:46 AM 20. According to NEC 110.14(A), if feeder lugs are used, the electrician must ensure that the lugs are suitable for making _____ connections.

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Chapter 04: Panelboards a. secure b. tight c. single d. multiple ANSWER: d POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/22/2023 10:46 AM DATE MODIFIED: 5/22/2023 10:47 AM 21. List two of the panelboard requirements located in NEC Article 408.

ANSWER: The following are NEC requirements for panelboards from Article 408: • Sized to a minimum of the electrical load to be supplied by the panelboard, 408.30 • Protected with an overcurrent protective device located in the panelboard, such as with a main breaker, or located remotely from the panelboard, such as by a feeder overcurrent device and an MLO panelboard, 408.36 POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:48 AM DATE MODIFIED: 5/22/2023 10:49 AM 22. List four panelboard requirements specified by NEC Article 110.

ANSWER: The following are some NEC 110 requirements for panelboards: • Have a short-circuit current rating of not less than the available fault current present, 110.10 • Installed in a professional and skilled manner, 110.12 • Marked with the manufacturer’s markings and field-applied hazard warning label, 110.21 • Have adequate working space, 110.26 POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:50 AM DATE MODIFIED: 5/22/2023 10:51 AM 23. What rules should be followed when setting the adjustable magnetic trip on a circuit breaker?

ANSWER: Two rules should be followed whenever the magnetic trip is set: • The lower the setting the greater protection provided.

• The setting should be lower than the value of the available fault current.

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Chapter 04: Panelboards REFERENCES: Panelboard Protective Device QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:51 AM DATE MODIFIED: 5/22/2023 10:54 AM 24. Which of the following needs and functions should be considered in circuit breaker selection?

ANSWER: The selection of the circuit breaker should be based on the necessity to: • Provide the proper overcurrent protection for the panelboard • Ensure a suitable voltage rating • Provide a sufficient interrupting rating • Coordinate the breaker(s) with other protective devices POINTS: 1 REFERENCES: Panelboard Protective Device QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:54 AM DATE MODIFIED: 5/22/2023 10:55 AM 25. When planning or diagramming a floor-mounted transformer supplying a power panelboard, what important components should be included?

ANSWER: The following components should be included: • Feeder busway • Cable tap box • Primary fused switch • Transformer • Secondary feeder protection • Conduits to motors or other loads • Controllers for motors or other loads • 3-phase, 3-wire panelboard • Wireway POINTS: 1 REFERENCES: Three-Phase, Three-Wire Panelboards QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:55 AM DATE MODIFIED: 5/22/2023 10:56 AM 26. Briefly discuss panelboard installations that do not require a main protective device and then outline situations in which individual protection is required.

ANSWER: A panelboard can have a main circuit breaker, or it could be a main-lug-only (MLO) panelboard with the feeder conductors connecting directly to the panelboard bus and protected by the feeder overcurrent protective device located remotely from the panelboard.

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Chapter 04: Panelboards Panelboards are available with standard main ratings of 100, 225, 400, 600, 800, and 1200 amperes.

POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:56 AM DATE MODIFIED: 5/22/2023 10:57 AM 27. Describe the methods by which a feeder can serve more than one panelboard.

ANSWER: The following two arrangements are permitted to allow one feeder to supply more than one panelboard: • Tapping the feeder conductors with taps to the panelboard • Use feeder lugs in the panelboards for a daisy chain-type connection POINTS: 1 REFERENCES: Panelboards QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/22/2023 10:57 AM DATE MODIFIED: 5/22/2023 10:58 AM

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Chapter 05: Trolley Busways 1. The industrial trolley bus is a _____-ampere, enclosed busbar electrical system. a. 50 b. 75 c. 100 d. 125 ANSWER: c POINTS: 1 REFERENCES: Three-Phase Trolley Busway.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:34 AM DATE MODIFIED: 5/27/2023 1:42 AM 2. A _____ section provides the means for removing or inserting trolleys. This section contains two hinged doors that open when a lever is raised. a. run b. drop-out c. switch d. curved ANSWER: b POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:34 AM DATE MODIFIED: 5/27/2023 1:42 AM 3. What shape are the standard segments used to construct trolley systems? a. straight b. semicircular c. triangular d. circular ANSWER: a POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:34 AM DATE MODIFIED: 5/27/2023 1:43 AM 4. The standard length of segments used for trolley systems is _____ft. a. 20 b. 5 Copyright Cengage Learning. Powered by Cognero.

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Chapter 05: Trolley Busways c. 6 d. 10 ANSWER: d POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:34 AM DATE MODIFIED: 5/27/2023 1:44 AM 5. The only tool needed to join the industrial-type trolley duct is a _____. a. hammer b. welder c. screwdriver d. rivet-gun ANSWER: c POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:35 AM DATE MODIFIED: 5/27/2023 1:44 AM 6. Each end of the trolley busway is capped with an end plate and _____ assembly. a. insulating b. welded c. securing d. bumper ANSWER: d POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:35 AM DATE MODIFIED: 5/27/2023 1:45 AM 7. The power supply from the panelboard is fed into a busway run through a _____. a. drop-in assembly b. standard hanger c. feed-in adapter d. trolley run ANSWER: c POINTS: 1 Copyright Cengage Learning. Powered by Cognero.

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Chapter 05: Trolley Busways REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:35 AM DATE MODIFIED: 5/27/2023 1:46 AM 8. The equipment and attachment plugs used with the duct system are _____, which eliminates several problems when portable tools having three-phase motors are used. a. grounded b. phase-rotated c. phase-reversed d. polarized ANSWER: d POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:35 AM DATE MODIFIED: 5/27/2023 1:47 AM 9. The trolley busway is equipped with two _____ busbars. a. aluminum b. copper c. silver d. cadmium-plated ANSWER: b POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:35 AM DATE MODIFIED: 5/27/2023 1:47 AM 10. A lighting system composed of _____ outlets and a _____ conduit system is not easily adaptable to changing requirements. a. fixed, polarized b. standard, standard c. fixed, standard d. fixed, fixed ANSWER: d POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

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Chapter 05: Trolley Busways HAS VARIABLES: False DATE CREATED: 5/27/2023 1:36 AM DATE MODIFIED: 5/27/2023 1:49 AM 11. One advantage of a system of luminaires suspended from a trolley system is that, in the event of extensive plant alterations, _____ sections are completely reusable. a. lamp b. cable c. wire d. duct ANSWER: d POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:36 AM DATE MODIFIED: 5/27/2023 1:51 AM 12. The 50-ampere lighting circuits used in the trolley systems are approved by _____. a. IEEE Institute of Electrical and Electronic Engineers b. NEMA National Electrical Manufacturers Association c. Underwriters Laboratories d. Wyle Laboratories ANSWER: c POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:36 AM DATE MODIFIED: 5/27/2023 1:52 AM 13. Messenger wires supporting the trolley lighting circuit are adjusted for tension by _____ located at the ends of the runs. a. pulleys b. bolts c. cables d. turnbuckles ANSWER: d POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:36 AM Copyright Cengage Learning. Powered by Cognero.

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Chapter 05: Trolley Busways DATE MODIFIED: 5/27/2023 1:52 AM 14. The lighting trolley is available in 5-ft (1.5-m) and 10-ft (3-m) sections, which are joined by _____ couplings. a. straight b. plain c. double d. circular ANSWER: b POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:37 AM DATE MODIFIED: 5/27/2023 1:53 AM 15. The couplings joining lighting trolley sections make a _____ connection, electrically and mechanically, between two duct sections and permit free passage of the trolleys along the duct runs. a. positive b. negative c. neutral d. perfect ANSWER: a POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:38 AM DATE MODIFIED: 5/27/2023 1:53 AM 16. To prevent arcing, trolleys should not be removed while they are _____. a. securely suspended b. completely de-energized c. under load d. mechanically connected ANSWER: c POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:40 AM DATE MODIFIED: 5/27/2023 1:54 AM 17. Luminaires are equipped with _____, which cause the lamps to fire at different times.

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Chapter 05: Trolley Busways a. transistors b. integrated circuits c. lead-lag adders d. phase adders ANSWER: c POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:40 AM DATE MODIFIED: 5/27/2023 1:55 AM 18. Commonly, 4-conductor type SJ rubber cords are used to connect various machines, the colors of the individual conductors are black, white, red, and _____. a. magenta b. green c. purple d. blue ANSWER: b POINTS: 1 REFERENCES: Lighting in the Boiler Room.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:40 AM DATE MODIFIED: 5/27/2023 1:56 AM 19. The hangers used to suspend trolley busways and join adjacent segments are formed from _____-gauge steel. a. 8 b. 12 c. 14 d. 10 ANSWER: b POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:41 AM DATE MODIFIED: 5/27/2023 1:56 AM 20. Bus drop safety springs are used to maintain the proper tension on the horizontal and vertical cord runs. These springs are available with 40-, 80-, and _____-pound ratings. a. 100 b. 120 Copyright Cengage Learning. Powered by Cognero.

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Chapter 05: Trolley Busways c. 150 d. 180 ANSWER: c POINTS: 1 REFERENCES: Lighting in the Boiler Room.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:41 AM DATE MODIFIED: 5/27/2023 1:57 AM 21. Suppose an industrial-type fluorescent luminaire includes two 215-watt lamps. What effect does the ballast have on the luminaire power losses? a. increases apparent power loss b. decreases real power loss c. decreases apparent power loss d. has no effect on power loss ANSWER: a POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Multiple Choice HAS VARIABLES: False DATE CREATED: 5/27/2023 1:57 AM DATE MODIFIED: 5/27/2023 1:58 AM 22. Describe the electrical connection between busbars and portable tools energized by trolleys.

ANSWER: The trolleys have six graphite bronze shoes. These shoes make contact with the busbars and provide a path that continues through the fuse cutout and receptacle to the heavy-duty, fourwire rubber cord. This cord is used to attach portable tools such as electric drills, buffers, grinders, and other equipment in the busway system.

POINTS: 1 REFERENCES: The Trolley Busway Runs.

QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 1:58 AM DATE MODIFIED: 5/27/2023 1:59 AM 23. Describe how a trolley system, installed over production and assembly lines, increases worker safety.

ANSWER: Trolleys move along with a particular object being assembled so that energized tools can be suspended vertically from the trolley. This system eliminates the need for and hazards of portable cords plugged into fixed outlets at the floor level.

POINTS: 1 REFERENCES: Three-Phase Trolley Busway.

QUESTION TYPE: Essay Copyright Cengage Learning. Powered by Cognero.

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Chapter 05: Trolley Busways HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 1:58 AM DATE MODIFIED: 5/27/2023 2:00 AM 24. Describe the luminaires used in the manufacturing area.

ANSWER: The luminaires used in the manufacturing area are industrial-type fluorescent luminaires.

Each luminaire uses two F96T12/CW/VHO lamps rated at 215 watts each. Due to power losses in the ballasts, the actual power loss is 450 volt-amperes per luminaire. The fluorescent ballasts used are all of the high power factor types, with individual fusing provided in accordance with 368.17. The luminaires are also equipped with lead-lag adders which cause the lamps to fire at different times, thereby eliminating the stroboscopic effect that occurs if individual lamps are used or if the lead-lag system is not used.

POINTS: 1 REFERENCES: Lighting in the Manufacturing Area QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 1:58 AM DATE MODIFIED: 5/27/2023 2:00 AM 25. What is the role of center feed-in boxes?

ANSWER: Center feed-in boxes are used to bring the electrical supply cables to the trolley busway. Each box has two adjustable couplings (one on each end of the box) connected by removable flexible jumper wires. In addition, the feed-in box has two sets of concentric knockouts that provide a means of bringing the feeding conduits into the duct system.

POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 1:58 AM DATE MODIFIED: 5/27/2023 2:01 AM 26. What advantages does a suspended lighting system have?

ANSWER: A lighting system composed of fixed outlets and a fixed conduit system is not easily adaptable to changing requirements. On the other hand, a system of luminaires suspended from a trolley system can be readily shifted from one location to another as desired. It is not necessary to take down or replace heavy conduit systems as would be required to change a fixed lighting outlet system. If extensive alternations or a major plant changeover requires the removal of the lighting trolley duct, the duct sections are completely reusable.

POINTS: 1 REFERENCES: Lighting in the Manufacturing Area.

QUESTION TYPE: Essay HAS VARIABLES: False Copyright Cengage Learning. Powered by Cognero.

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Chapter 05: Trolley Busways STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 2:01 AM DATE MODIFIED: 5/27/2023 2:02 AM 27. Why is the structure of cord grips important?

ANSWER: Cord grips are constructed in a basketweave pattern. The grips are tubular in shape and are made from strands of galvanized plow steel wire. Grips are available in a variety of sizes to fit most cables or cords. When strain or tension is placed on the rubber cord so that it is pulled taut, the basket structure of the cord grip contracts to apply a stronger grip on the cord.

POINTS: 1 REFERENCES: Lighting in the Boiler Room.

QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 2:01 AM DATE MODIFIED: 5/27/2023 2:05 AM 28. What is the purpose of bus drop safety springs, and what is the basis for the selection of spring force?

ANSWER: Bus drop safety springs are used to maintain the proper tension on the horizontal and vertical cord runs. These springs are available with 40-, 80-, and 150-pound ratings. The selection of the proper spring depends upon the weight and length of the cord being supported.

POINTS: 1 REFERENCES: Lighting in the Boiler Room.

QUESTION TYPE: Essay HAS VARIABLES: False STUDENT ENTRY MODE: Basic DATE CREATED: 5/27/2023 2:02 AM DATE MODIFIED: 5/27/2023 2:06 AM

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