Deck 13: The Electric Service

Question 1

GFPE monitors are designed to sense faults only.

A)phase-to-phase
B)phase-to-ground
C)3-phase
D)phase-to-neutral

Answer 1

B

Question 2

GFCI protection can be attained using GFCI circuit breakers or GFCI .

A)switchboards
B)monitors
C)receptacles
D)fuses

Answer 2

C

Question 3

The connection scheme has the advantage of being able to provide either 3-phase or 3-phase and single-phase power using only two transformers.

A)three-wire delta
B)4-wire wye
C)open delta
D)single-phase

Answer 3

C

Question 4

When is ground-fault protection of equipment not required?

Question 5

NEC 110.16 has a requirement for placing a notice on certain equipment to warn qualified persons of the serious hazard of flash events.

A)arc
B)current
C)lightning
D)circuit

Question 6

The temperatures of an electrical arc, such as might occur on a 480/277-volt solidly grounded, wye-connected system, are .

A)at the boiling point of water
B)not hot enough to melt metals
C)safe for humans
D)hotter than the surface of the sun

Question 7

Dry-type transformers are widely used because they are than comparably rated liquid-filled transformers.

A)better dielectrics
B)better conductors
C)heavier in weight
D)lighter in weight

Question 8

What liquid was used in the past in liquid-filled transformers? Is it still in use?

Question 9

When and how does primary high-voltage metering take place?

Question 10

Throughout this country, and for that matter, throughout the world, is(are) the common reference point for all electrical systems.

A)the atmosphere
B)a standard metal plate
C)the earth
D)individual building walls

Question 11

occur when an ungrounded "hot" conductor comes in contact with a grounded surface or grounded equipment.

A)Circuit breakings
B)Ground faults
C)Groundings
D)Arc blasts

Question 12

What is an effective ground-fault current path?

Question 13

What are the advantages of proper bonding and grounding?

Question 14

NEC 230.71 permits not more than disconnects to serve as the building disconnecting means.

A)6
B)10
C)14
D)18

Question 15

Utilities make up the connections on the line side and load side of their transformers according to the requirements.

A)NFPA
B)NESC
C)TEK
D)UL

Question 16

The two basic methods of metering are primary high-voltage metering and .

A)intermediate-voltage metering
B)pulsed metering
C)secondary high-voltage metering
D)low-voltage metering

Question 17

NEC 250.64(C) states that grounding electrode conductors generally are not permitted to be .

A)cut
B)spliced
C)joined
D)integrated

Question 18

Today's liquid­filled transformers have their windings immersed in highly refined mineral oil (combustible), silicone fluid, edible seed oil-based dielectric coolant, or other acceptable nontoxic liquids that have properties.

A)high dielectric
B)high conductance
C)low dielectric
D)photoactive

Question 19

The is defined in NEC Article 100 as the point of connection between the facilities of the serving utility and the premises wiring.

A)open delta
B)singular phase
C)service point
D)transformer

Question 20

The lower the of the grounding path, the greater the ground-fault current.

A)length
B)elevation
C)magnetic permeability
D)impedance