Week 3 Grounding & Bonding

18. Bare aluminum or copper-clad aluminum grounding electrode conductors are permitted to be installed where in direct contact with masonry. True False

False

20. With bonding conductor connections to electrodes, connections depending on solder are permitted. True False

False

9. If overcurrent protection is not provided at the source of a separately derived system, the grounding electrode conductor must be electrically isolated from the disconnecting means at the building or structure. True False

False

10. When one of the system conductors is grounded at the transformer, the other system conductors rise to a specific voltage above ground. True False

True

19. Concrete-encased electrodes of existing buildings or structures are not required to be part of the grounding electrode system if the steel reinforcing bars or rods are not accessible for use without disturbing the concrete. True False

True

8. Ground detection on ungrounded systems has direct operational benefits to industrial plants because the first ground fault will be detected and indicated. True False

True

11. If a single rod, pipe, or plate grounding electrode has a resistance to earth of ____ or less, the supplemental electrode shall not be required. a. 25 ohms b. 50 ohms c. 75 ohms d. 100 ohms

a. 25 ohms

4. When using a main bonding jumper wire as a wire or busbar, a(n) ____ is placed on the main bonding jumper to measure the current flowing on it. a. current transformer b. utility breaker c. grounded conductor d. grounding electrode

a. current transformer

14. Where ____ or more grounding electrodes are bonded together, a grounding electrode system is established. a. two b. three c. five d. six

a. two

6. The term ___________ is defined in NEC® Article 100 and means, as far as equipment is concerned, "capable of being reached for operation, renewal, and inspection."

accessible

15. ____ copper is the largest grounding electrode conductor that is required to be installed where the conductor connects directly to the rod, pipe, or plate grounding electrode. a. AWG3 b. AWG6 c. AWG9 d. AWG12

b. AWG6

13. There is no maximum or minimum size of water pipe to determine whether the metal water pipe is required to be used as a grounding electrode. The ____ of underground metal water pipe in contact with the earth is the qualifying condition. a. width b. length c. diameter d. circumference

b. length

1. If a grounding electrode conductor is connected at the first system disconnecting means or overcurrent device, the bonding jumper is sized the same as the ____. a. equipment bonding jumper b. neutral conductor c. supply-side bonding jumper d. positive conductor

b. neutral conductor

5. ____ locations are those that are hazardous because of easily ignitable fibers or flyings, but in which such fibers or flyings are NOT likely to be in suspension in the air in quantities sufficient to produce ignitable mixtures. a. Class I b. Class II c. Class III d. Class IV

c. Class III

2. Three-phase, 4-wire, wye-connected systems are created by connecting ____ single-phase transformers or windings in a "Y" (wye) configuration. a. one b. two c. three d. four

c. three

12. The supplemental electrode is permitted to be connected to the electrical system at several locations, with the exception of the ____. a. grounding electrode conductor b. grounded service-entrance conductor c. water pipe d. nonflexible grounded service raceway

c. water pipe

3. When a main bonding jumper or a system bonding jumper is a screw only, the screw must be identified with a ____ finish that is required to be visible with the screw installed. a. red b. yellow c. blue d. green

d. green

7. The __________ bonding jumper runs from the service cabinet to the load side of the grounding impedance.

equipment

17. If piping is underground, metal, and used for water, regardless of the type of water and whether for domestic use or irrigation, drainage, or fire protection purposes, it must be used as a(n) __________ if it is in contact with the earth for ten feet or more.

grounding electrode

16. For large services, busbar may be used from the __________ to service equipment.

transformer vault