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

Accepted Answer

Backfeed in electrical systems can cause unexpected energization, posing serious risks of shock and electrocution, leading to injuries and fatalities, hence being referred to as "the Hidden Killer."

Question 2

Generators must be oversized when supplying ____ loads to reduce heating and voltage waveform distortion.
A)linear
B)nonlinear
C)resistive
D)oscillating

Accepted Answer

Nonlinear loads can cause heating and voltage waveform distortion due to the harmonics they generate. Oversizing generators helps mitigate these effects by providing additional capacity to handle the irregular current draw and reduce the impact of the harmonics.

Question 3

When are self-contained emergency power systems used?

Accepted Answer

​ 
 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

Accepted Answer

Diesel fuel is commonly used in emergency generators due to its energy efficiency and safety in storage compared to other fuels like gasoline.

Question 5

What is the mechanism behind the generation of backfeed?

Accepted Answer

The answer of What is the mechanism behind the generation...

Question 6

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

Accepted Answer

The answer of Why is it important to accurately determine...

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

Accepted Answer

Manufacturers often integrate the transfer switch into the panelboard for installations dedicated to emergency or standby power, streamlining the setup and making it more efficient.

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

Accepted Answer

The starting kilovolt-amperes for a motor is equivalent to the locked-rotor kilovolt-amperes. This is because when a motor starts, the rotor is initially at a standstill (locked), and the starting current is typically much higher than the running current, reflecting the locked-rotor condition.

Question 9

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

Accepted Answer

The answer of What are the advantages and disadvantages of...

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

Accepted Answer

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

Question 11

The Life Safety Code is another name for ____.
A)NFPA 99
B)NFPA 101
C)NFPA 110
D)IEEE 446

Accepted Answer

The Life Safety Code is another name for NFPA 101, which is a standard that provides criteria for the design, construction, operation, and maintenance of buildings and structures for safety from fire and similar emergencies.

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

Accepted Answer

Key-operated switches are used in emergency systems to prevent unauthorized access or operation of the luminaires, ensuring that the emergency lighting remains reliable and is only used when necessary.

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

Accepted Answer

Uninterruptible Power Supply (UPS) systems are designed to provide clean, stable power to sensitive electronic equipment like computers, ensuring they remain operational during power disturbances or outages.

Question 14

What is a legally required standby system?

Accepted Answer

The answer of 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

Accepted Answer

The standby power system must have the capacity to provide the sum of the starting kilovolt-ampere values for the two motors to ensure both can start simultaneously without overloading the system.

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

Accepted Answer

According to NEC 700.6(A), a derangement signal is required for emergency systems, which includes a signal device with both audible and visual alarms to indicate a malfunction.

Question 17

Generator units with a capacity greater than 15 kilowatts generally use ____ cooling.
A)LP gas
B)air
C)liquid
D)no

Accepted Answer

Generator units with a capacity greater than 15 kilowatts typically require more efficient cooling methods due to the higher heat output, and liquid cooling systems are more effective for this purpose compared to air cooling.

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

Accepted Answer

Hospitals generally have the most stringent requirements due to the complexity and critical nature of the healthcare services they provide, including surgeries, emergency care, and intensive care units, which necessitate higher standards for electrical safety and reliability as outlined in NEC Article 517.

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

Accepted Answer

The main purpose of an emergency system is to ensure that power and illumination essential for safety to human life are automatically supplied, distributed, and controlled in the event of a normal power supply interruption.

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

Accepted Answer

According to NEC Section 110.9, switches and fuses must have an interrupting capacity not less than the available short-circuit current at their supply terminals. This ensures that they can safely interrupt the maximum possible fault current they might have to deal with.

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

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

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

When are self-contained emergency power systems used?

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

What is the mechanism behind the generation of backfeed?

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

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.

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

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

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

The Life Safety Code is another name for ____.

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

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

What is a legally required standby system?

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.

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

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

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.

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.

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.