Grounding and Bonding

Question 1

A grounding electrode system is generally required for each building or structure served by a feeder.

Answer 1

True

Question 2

According to the NEC, that which is built or constructed, other than equipment, best defines which of the following?

Answer 2

Structure

Question 3

If the overcurrent protective device is located on a generator outside that supplies a separate building or structure, then the feeder is on the load side of an overcurrent device. In this case, the equipment bonding jumper (load side) with the feeder is sized based on the requirements in Section 250.102(C).

Answer 3

False

Question 4

If the overcurrent protective device is not located on a generator outside that supplies a separate building or structure, then the feeder is on the line side of an overcurrent device. In this case, the supply-side bonding jumper with the feeder is sized based on the requirements in 250.102(C).

Answer 4

True

Question 5

A structure is constructed or built and does not include electrical equipment.

Answer 5

True

Question 6

Which of the following electrical systems is required to be grounded?

a. 120V, single-phase system
b. 240V, 3-phase, 3-wire, delta-connected system
c. 480V, 3-phase, 3-wire, delta-connected system
d. 2,300V, 3-phase, 3-wire, delta-connected system
e. 4,600V, 3-phase, 3-wire, delta-connected system

Answer 6

a. 120V, single-phase system

Correct

Question 7

Which of the following systems is not required to be grounded because, if grounded, the phase-to-ground voltage would exceed 150?

a. 50V, single-phase system
b. 120V, single-phase system
c. 120/240V, single-phase, 3-wire system
d. 480V, 3-phase delta system

Answer 7

d. 480V, 3-phase delta system Correct

Question 8

Class 2 load-side circuits for suspended ceiling low-voltage power grid distribution systems are required to be supplied by grounded systems.

Answer 8

False

Question 9

Which of the following systems is required to be grounded?

a. 120V, single-phase system
b. 240V, 3-phase, 3-wire, delta system
c. 480V, 3-phase, delta system
d. 600V, 3-phase system

Answer 9

a. 120V, single-phase system Correct

Question 10

Where a system bonding jumper for a separately derived system is a wire type, it is required to be sized using Table 250.102(C)(1) or the 12.5% rule based on the size of the largest derived ungrounded phase conductor(s) or the total circular mil (cm) area of all conductors connected to any one ungrounded phase at the source.

Answer 10

True

Question 11

If a generator is installed on a premises wiring system, it must be grounded as a separately derived system if there is a switching action in the grounded conductor through the transfer switch.

Answer 11

True

Question 12

The grounding electrode conductor for a single separately derived system is required to be sized using which NEC table?

Answer 12

Table 250.66

Question 13

The grounding electrode conductor for a single separately derived system in accordance with ? must be sized at a minimum in accordance with the sizes in ? , based on the circular mil area of the largest ungrounded system conductor.

Answer 13

250.33(A)(5)/ Table 250.66

Question 14

Where grounding electrode conductor taps are used for multiple separately derived systems, each grounding electrode conductor tap must be sized using Table 250.66 based on the largest ungrounded derived phase conductor(s) of the individual derived system it serves.

Answer 14

True

Question 15

Metal water piping and interconnected metal building framing that exists in the area served by a separately derived system is required to be bonded to the grounded conductor of that separately derived system, and ? is used to size this bonding jumper or conductor.

Answer 15

Table 250.102(C)(1)

Question 16

What is the minimum size required for the bonding conductor for an equipotential plane in an agricultural facility?

Answer 16

8 AWG Copper

Question 17

A distance of at least ? must be maintained from a nonmetallic conduit containing a high-voltage circuit operating at above 100 hertz.

Answer 17

1 3/4”

Question 18

Remote parts of a section sign or outline lighting system supplied by a Class 2 power supply are required to be bonded to the equipment grounding conductor of the branch circuit supplying the system.

Answer 18

False

Question 19

A(n) ? is a specific grounding and bonding device that provides a means for connecting bonding conductors for communications systems to the grounding electrode system.

Answer 19

Intersystem Bonding Termination

Question 20

The bonding conductor or grounding electrode conductor for a communications system is required to be ? and shall be permitted to be insulated, covered, or bare.

Answer 20

Listed

Question 21

In existing buildings or structures where any of the intersystem bonding and grounding electrode conductors required by 770.100(B)(2), 800.100(B)(2), and 810.21(F)(2) exist, installation of the intersystem bonding termination is not required. In this case, an accessible means external to enclosures for connecting intersystem bonding and grounding electrode conductors is permitted at the service equipment and at the disconnecting means for any additional buildings or structures by which one of the following means?

a. An exposed grounding electrode conductor
b. Approved means for the external connection of a copper or other corrosion-resistant bonding or grounding electrode conductor to the grounded raceway or equipment
c. Exposed nonflexible metallic raceways
d. Any of the above locations

Answer 21

d. Any of the above locations

Correct

Question 22

Which of the following are common shock severity factors for humans?

a. Amount of current
b. Frequency of the circuit
c. Length of time
d. Path across the body
e. Size of the person
f. All of the above

Answer 22

f. All of the above

Correct

Question 23

Ground-fault circuit interrupters provide protection for persons.

Answer 23

True

Question 24

A(n) ? is a device intended for the protection of personnel that functions to deenergize a circuit or portion thereof within an established period of time when a current to ground exceeds the values established for a Class A device.

Answer 24

Ground-fault Circuit Interrupter

Question 25

The circuit-breaker types of GFCI open the entire branch circuit if a ground fault occurs, while outlet types only open a portion of the circuit.

Answer 25

True

Question 26

A ground-fault circuit interrupter operates simply by measuring the current in the supply and return current-carrying conductors of the circuit and by monitoring for an imbalance that exceeds ? .

Answer 26

4 to 6 mA

Question 27

A non–grounding-type receptacle is permitted to be replaced with another non–grounding-type receptacle where no grounding means exists in the outlet.

Answer 27

True

Question 28

? is defined as a system intended to provide protection of equipment from damaging line-to-ground fault currents by operating to cause a disconnecting means to open all ungrounded conductors of the faulted circuit.

Answer 28

Ground-fault protection of equipment

Question 29

Which of the following are common methods of grounding systems over 1,000 volts?

a. Grounded through an impedance device
b. Grounded through a set of grounding transformers
c. Solidly grounded I
d. All of the above

Answer 29

d. All of the above

Correct

Question 30

Which of the following are the primary purposes of shielding for medium- and high-voltage cables?

a. To carry the ground-fault current to facilitate operation of ground-fault protective devices in the event of an electrical cable fault
b. To confine the voltage stresses to the insulation
c. To dissipate insulation leakage current
d. To drain off the capacitive charging current
e. All of the above

Answer 30

e. All of the above

Correct

Question 31

All metallic shields (ribbon tape shields or concentric stranding) are required to be directly connected to which of the following?

I. A grounding busbar
II. A grounding electrode
III. A grounding electrode conductor
IV. An equipment grounding conductor
V. A neutral conductor
VI. An ungrounded phase conductor

Answer 31

a. I., II., III., and IV. Correct

Note: The question seeks the Code answer. While the neutral may be connected to any of the conductors in choices a., b., c., or d., the NEC does specify the connection locations, and the neutral of a grounded or ungrounded system is not provided. See NEC 310.10(E).
The correct answer is: I., II., III., and IV.