Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
Solution and Answer Guide
PHIL SIMMONS AND MARK C. ODE, ELECTRICAL GROUNDING & BONDING, EDITION: 8TH,
2027, 9798214133287; U NIT 1: GENERAL
TABLE OF CONTENTS
Answers To Review Questions......................................................................................1
ANSWERS TO REVIEW QUESTIONS
1. Which of the following NEC® sections provides the requirement for the concept that the requirements for
grounding in Chapter 5 through Chapter 7 can modify or supplement the rules in Chapter 1 through
Chapter 7 ?
a. 517.17
b. 250.118
c. 250.3
d. 90.3 (NEC® 90.3)
2. Which of the following statements is correct about the style in which Article 250 is written?
a. It is generally written in “performance” style that states the safety goals to be achieved.
b. It is generally written in a “legal” style so that the installer will be more likely to comply with the
requirements.
c. It is generally written in “prescriptive” style that states how the installation must
be made. (Text Page)
d. It is written in neither “performance” nor “prescriptive” style.
3. Which of the following statements about the reasons for grounding an electrical system is not true?
a. To limit the overvoltage imposed by lightning
b. To limit the overvoltage from contact with utility high-voltage lines
c. To provide a low-impedance ground-fault return path (NEC® 250.4(A)(1); Text Page)
d. To stabilize the voltage of the system to earth during normal operation
4. Which of the following statements about bonding is not true?
a. Bonding completes a path for fault current to flow.
b. Bonding conductive parts together keeps the conductive materials at the same electrical potential.
c. Bonding’s primary purpose is to make an earth connection. (NEC® 250.4(A)(3); Text
Page)
d. Bonding has the effect of eliminating any shock hazard between bonded enclosures or parts.
5. Which of the following statements about providing an effective ground-fault current path is not true?
a. It must be a reliable rather than a temporary path.
b. It must provide a low-impedance circuit.
c. It must be capable of safely carrying the maximum ground-fault current likely to be imposed.
d. It permits the earth to be considered an effective ground-fault current path. (NEC®
250.4(A)(5); Text Page)
6. Which of the following is not a purpose for grounding equipment associated with an ungrounded system?
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 1
accessible website, in whole or in part.
,Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
a. Even though the system is not grounded, metallic enclosures for the system conductors must be
grounded and bonded to protect against shock hazards.
b. If the system is not required to be grounded, there is no requirement for the
equipment associated with the ungrounded system to be grounded. (NEC® 250.4(B)
(1); Text Page)
c. Even though the system is not grounded, grounding the enclosure provides a path for overvoltages to
flow to the earth.
d. Even though the system is not grounded, bonding the enclosures together provides a path for fault
current to flow.
7. Which of the following statements does not describe objectionable current?
a. Neutral current flowing over the neutral grounding conductor (NEC® 250.6(A); Text
Page)
b. Neutral current flowing over the equipment grounding conductor
c. Neutral current flowing over cable shields
d. Neutral current flowing over metal raceways
8. Which of the following connection methods is not permitted to be used to connect grounding conductors to
enclosures or equipment?
a. Exothermic welding
b. Listed pressure connectors
c. Listed clamps
d. Sheet metal screws (NEC® 250.8(A) ; Text Page)
9. Which of the following statements about conductor connectors or conductor connections is not correct?
a. The marking “AL/CU” on the connector means that it is suitable for both copper and aluminum wire
connections.
b. The marking “AL/CU” on the connector means that it is acceptable to connect
copper and aluminum in direct contact. (NEC® 110.14; Text Page)
c. A wire connector that is not marked for the type of conductor material is suitable for only copper
connections.
d. Connectors that are suitable for connecting more than one conductor are marked to indicate the
suitability.
10. Which of the following statements about painted electrical enclosures is not true?
a. Paint used on electrical enclosures can be thought of as an insulator.
b. Where conduit, electrical metallic tubing, or metal cables are connected to these enclosures, the paint
should be removed.
c. Fittings and locknuts are readily available that are listed to make removal of
paint unnecessary. (Text Page)
d. Every connection in the ground return path should be evaluated to ensure it is a good, solid connection
that is capable of carrying fault current.
11. The typical voltages for a 120/240 volt, 3-phase, 4-wire, delta-connected system are
a. 120 volts phase A to phase B.
b. 208 volts phase B to ground. (Text, Figure 1-4)
c. 208 volts phase B to phase C.
d. 240 volts phase C to ground.
12. A fault-return path of ___________ is essential for proper action of the overcurrent device on the supply
side.
a. low impedance (Text Page)
b. low resistance
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 2
accessible website, in whole or in part.
,Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
c. low inductance
d. low capacitance
13. The curved portion of the circuit breaker time-current chart is best described as the
a. one-cycle tripping time.
b. time-delay component. (Text Page)
c. instantaneous-trip component.
d. total clearing time.
14. Keeping all circuit conductors, including the equipment grounding conductor, in the same raceway, cable
or similar enclosure is essential to keep the _____________ as low as practicable.
a. impedance (Text Page and Figure 1-10)
b. resistance
c. inductance
d. capacitance
15. If more than one path exists for neutral current to flow, current will flow
a. in only the path of lowest resistance.
b. in only the paths that are in series.
c. in all paths that are available. (Text Page)
d. only when there is a ground-fault.
16. Temporary currents flowing in the circuit until the overcurrent device opens are considered “objectionable”
and are not permitted.
a. True
b. False (250.6(C))
17. Due to data processing equipment being sensitive to electrical noise on the equipment grounding conductor,
it is permitted to isolate the equipment from the “dirty ground” and connect the equipment only to a local
ground rod.
a. True
b. False (250.6(D) and Text)
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 3
accessible website, in whole or in part.
, Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
18. A sheet metal enclosure must be not less than thick if a machine screw type fastener of the 10-32 size is
used to connect an equipment grounding conductor to the enclosure.
a. 1/32 in.
b. 1/16 in. (1/16 in. thick will allow 2 threads, 32 16 = 2 (250.8(A)(5))
c. 3/32 in.
d. 1/8 in.
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 4
accessible website, in whole or in part.
Solution and Answer Guide
PHIL SIMMONS AND MARK C. ODE, ELECTRICAL GROUNDING & BONDING, EDITION: 8TH,
2027, 9798214133287; U NIT 1: GENERAL
TABLE OF CONTENTS
Answers To Review Questions......................................................................................1
ANSWERS TO REVIEW QUESTIONS
1. Which of the following NEC® sections provides the requirement for the concept that the requirements for
grounding in Chapter 5 through Chapter 7 can modify or supplement the rules in Chapter 1 through
Chapter 7 ?
a. 517.17
b. 250.118
c. 250.3
d. 90.3 (NEC® 90.3)
2. Which of the following statements is correct about the style in which Article 250 is written?
a. It is generally written in “performance” style that states the safety goals to be achieved.
b. It is generally written in a “legal” style so that the installer will be more likely to comply with the
requirements.
c. It is generally written in “prescriptive” style that states how the installation must
be made. (Text Page)
d. It is written in neither “performance” nor “prescriptive” style.
3. Which of the following statements about the reasons for grounding an electrical system is not true?
a. To limit the overvoltage imposed by lightning
b. To limit the overvoltage from contact with utility high-voltage lines
c. To provide a low-impedance ground-fault return path (NEC® 250.4(A)(1); Text Page)
d. To stabilize the voltage of the system to earth during normal operation
4. Which of the following statements about bonding is not true?
a. Bonding completes a path for fault current to flow.
b. Bonding conductive parts together keeps the conductive materials at the same electrical potential.
c. Bonding’s primary purpose is to make an earth connection. (NEC® 250.4(A)(3); Text
Page)
d. Bonding has the effect of eliminating any shock hazard between bonded enclosures or parts.
5. Which of the following statements about providing an effective ground-fault current path is not true?
a. It must be a reliable rather than a temporary path.
b. It must provide a low-impedance circuit.
c. It must be capable of safely carrying the maximum ground-fault current likely to be imposed.
d. It permits the earth to be considered an effective ground-fault current path. (NEC®
250.4(A)(5); Text Page)
6. Which of the following is not a purpose for grounding equipment associated with an ungrounded system?
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 1
accessible website, in whole or in part.
,Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
a. Even though the system is not grounded, metallic enclosures for the system conductors must be
grounded and bonded to protect against shock hazards.
b. If the system is not required to be grounded, there is no requirement for the
equipment associated with the ungrounded system to be grounded. (NEC® 250.4(B)
(1); Text Page)
c. Even though the system is not grounded, grounding the enclosure provides a path for overvoltages to
flow to the earth.
d. Even though the system is not grounded, bonding the enclosures together provides a path for fault
current to flow.
7. Which of the following statements does not describe objectionable current?
a. Neutral current flowing over the neutral grounding conductor (NEC® 250.6(A); Text
Page)
b. Neutral current flowing over the equipment grounding conductor
c. Neutral current flowing over cable shields
d. Neutral current flowing over metal raceways
8. Which of the following connection methods is not permitted to be used to connect grounding conductors to
enclosures or equipment?
a. Exothermic welding
b. Listed pressure connectors
c. Listed clamps
d. Sheet metal screws (NEC® 250.8(A) ; Text Page)
9. Which of the following statements about conductor connectors or conductor connections is not correct?
a. The marking “AL/CU” on the connector means that it is suitable for both copper and aluminum wire
connections.
b. The marking “AL/CU” on the connector means that it is acceptable to connect
copper and aluminum in direct contact. (NEC® 110.14; Text Page)
c. A wire connector that is not marked for the type of conductor material is suitable for only copper
connections.
d. Connectors that are suitable for connecting more than one conductor are marked to indicate the
suitability.
10. Which of the following statements about painted electrical enclosures is not true?
a. Paint used on electrical enclosures can be thought of as an insulator.
b. Where conduit, electrical metallic tubing, or metal cables are connected to these enclosures, the paint
should be removed.
c. Fittings and locknuts are readily available that are listed to make removal of
paint unnecessary. (Text Page)
d. Every connection in the ground return path should be evaluated to ensure it is a good, solid connection
that is capable of carrying fault current.
11. The typical voltages for a 120/240 volt, 3-phase, 4-wire, delta-connected system are
a. 120 volts phase A to phase B.
b. 208 volts phase B to ground. (Text, Figure 1-4)
c. 208 volts phase B to phase C.
d. 240 volts phase C to ground.
12. A fault-return path of ___________ is essential for proper action of the overcurrent device on the supply
side.
a. low impedance (Text Page)
b. low resistance
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 2
accessible website, in whole or in part.
,Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
c. low inductance
d. low capacitance
13. The curved portion of the circuit breaker time-current chart is best described as the
a. one-cycle tripping time.
b. time-delay component. (Text Page)
c. instantaneous-trip component.
d. total clearing time.
14. Keeping all circuit conductors, including the equipment grounding conductor, in the same raceway, cable
or similar enclosure is essential to keep the _____________ as low as practicable.
a. impedance (Text Page and Figure 1-10)
b. resistance
c. inductance
d. capacitance
15. If more than one path exists for neutral current to flow, current will flow
a. in only the path of lowest resistance.
b. in only the paths that are in series.
c. in all paths that are available. (Text Page)
d. only when there is a ground-fault.
16. Temporary currents flowing in the circuit until the overcurrent device opens are considered “objectionable”
and are not permitted.
a. True
b. False (250.6(C))
17. Due to data processing equipment being sensitive to electrical noise on the equipment grounding conductor,
it is permitted to isolate the equipment from the “dirty ground” and connect the equipment only to a local
ground rod.
a. True
b. False (250.6(D) and Text)
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 3
accessible website, in whole or in part.
, Solution and Answer Guide: Phil Simmons and Mark C. Ode, Electrical Grounding & Bonding, Edition: 8th, 2027, 9798214133287; Unit 1: General
18. A sheet metal enclosure must be not less than thick if a machine screw type fastener of the 10-32 size is
used to connect an equipment grounding conductor to the enclosure.
a. 1/32 in.
b. 1/16 in. (1/16 in. thick will allow 2 threads, 32 16 = 2 (250.8(A)(5))
c. 3/32 in.
d. 1/8 in.
© 2027 Cengage Learning, Inc. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly 4
accessible website, in whole or in part.
