Deck 2: System Grounding

Question 1

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

Answer 1

C

Question 2

____ 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

Answer 2

C

Question 3

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

Answer 3

B

Question 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

Question 5

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

Question 6

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

Question 7

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."

Question 8

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.

Question 9

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

Question 10

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