Deck 16: Emergency, Legally Required Standby, and Optional Standby Power Systems

Question 1

There have been many injuries and deaths as a result of ____; it has been called "the Hidden Killer."

A)backfeed
B)harmonic current
C)triplens
D)overcurrent

Answer 1

A

Question 2

Generators must be oversized when supplying ____ loads to reduce heating and voltage waveform distortion.

A)linear
B)nonlinear
C)resistive
D)oscillating

Answer 2

B

Question 3

When are self-contained emergency power systems used?

Answer 3

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When the need for emergency power is confined to a definite area, such as a stairway or exit hallway, and the power demand in this area is low, self-contained battery-powered units are a convenient and efficient means of providing power. These are referred to as "unit equipment." In general, these units are wall mounted and are connected to the normal source by permanent wiring methods or at times by flexible cord if so supplied by the manufacturer. Under normal conditions, this regular source powers a regulated battery charger to keep the battery at full power. When the normal power fails, the circuit is completed automatically to one or more lamps that provide enough light to the area to permit its use, such as lighting a stairway sufficiently to allow people to leave the building. Battery-powered units are commonly used in exit signs, stairwells, hallways, shopping centers, supermarkets, and other public structures.

Question 4

Fuels that may be used in an emergency generator are LPG (liquid propane)gas, natural gas, gasoline, or ____.

A)fusel
B)diesel fuel
C)ethanol
D)kerosene

Question 5

What is the mechanism behind the generation of backfeed?

Question 6

Why is it important to accurately determine the capacity of a power system?

Question 7

Manufacturers of generators, transfer switches, and signaling devices also provide panelboards that have the ____ built right into the panelboard. This is a nice feature for installations where one panelboard is to serve the emergency or standby power requirements.

A)alternators
B)emergency circuit
C)transfer switch
D)voltage switch

Question 8

The starting kilovolt-amperes for a motor is equivalent to the ____ kilovolt-amperes of the motor.

A)locked-rotor
B)stator
C)armature
D)rectified

Question 9

What are the advantages and disadvantages of selecting diesel fuel to drive a generator engine?

Question 10

NEC 701.12( G )____ the connection for a legally required standby system to be made ahead of, but not within, the main service disconnect.

A)mandates
B)disallows
C)permits
D)discourages

Question 11

The Life Safety Code is another name for ____.

A)NFPA 99
B)NFPA 101
C)NFPA 110
D)IEEE 446

Question 12

In a typical branch-circuit installation for an emergency system, ____-operated switches are installed to prevent unauthorized personnel from operating the luminaires.

A)fingerprint
B)voice
C)light
D)key

Question 13

____ power supply systems are often installed to provide "clean power" to critical loads such as computers.

A)Uninterruptible
B)Unitary
C)UNIX
D)Unconditional

Question 14

What is a legally required standby system?

Question 15

If two motors are to be started at the same time, the standby power system must have the capacity to provide the ____ of the starting kilovolt-ampere values for the two motors.

A)higher
B)lower
C)product
D)sum

Question 16

According to NEC 700.6(A), a(n)____ is required for emergency systems, consisting of a signal device with both audible and visual alarms.

A)emergency siren
B)legally required standby
C)derangement signal
D)alarm composite

Question 17

Generator units with a capacity greater than 15 kilowatts generally use ____ cooling.

A)LP gas
B)air
C)liquid
D)no

Question 18

Among the types of healthcare facilities covered in NEC Article 517, ____ generally have the most stringent requirements, and clinics and medical and dental offices have the least stringent requirements.

A)hospitals
B)psychiatric facilities
C)nursing homes
D)ambulatory care centers

Question 19

The main purpose of a(n)____ system is to automatically come on to supply, distribute, and control power and illumination essential for safety to human life in the event that the normal supply of power is interrupted.

A)emergency
B)legally required standby
C)optional standby
D)overcurrent

Question 20

According to NEC 110.9 , switches and fuses must have a(n)____ capacity not less than the available short-circuit current at their supply terminals.

A)partial
B)total
C)interrupting
D)generating