Question 1

Which of the following is not an advantage of a three -phase motor over a single -phase motor?

Accepted Answer

A)  Torque output is constant 
B)  Manufacturing costs are less 
C)  Size is small relative to its horsepower 
D)  Rotor is laminated iron 
A)  Torque output is constant 
B)  Manufacturing costs are less 
C)  Size is small relative to its horsepower 
D)  Rotor is laminated iron

Question 2

The speed of the compound motors can be controlled with an adjustment to the shunt winding current.

Accepted Answer

A) True 
 B)False

Question 3

Flux lines exit from the north pole and re -enter through the south pole.

Accepted Answer

A) True 
 B)False

Question 4

Match the overload block with its operation.
-Bimetallic

Accepted Answer

A)  Uses dissimilar materials 
B)  Uses motor voltage 
C)  Uses motor current 
D)  Uses melting poin 
A)  Uses dissimilar materials 
B)  Uses motor voltage 
C)  Uses motor current 
D)  Uses melting poin

Question 5

Match the overload block with its operation.
-Eutectic

Accepted Answer

A)  Uses dissimilar materials 
B)  Uses motor voltage 
C)  Uses motor current 
D)  Uses melting poin 
A)  Uses dissimilar materials 
B)  Uses motor voltage 
C)  Uses motor current 
D)  Uses melting poin

Question 6

In a squirrel cage three -phase induction motor, the rotor resistance is equal to the rotor inductive reactance at the pull -out point.

Accepted Answer

A) True 
 B)False

Question 7

Which of the following is not a component of a DC motor starter?

Accepted Answer

A)  Arc quencher 
B)  Contactor 
C)  Overload relay 
D)  Heater 
E)  Braking relay 
A)  Arc quencher 
B)  Contactor 
C)  Overload relay 
D)  Heater 
E)  Braking relay

Question 8

AC motors are available as single phase motors, typically less than 3 hp.

Accepted Answer

A) True 
 B)False

Question 9

If brushes wear out, they can damage the commutator.

Accepted Answer

A) True 
 B)False

Question 10

For a motor with service factor of 1.2, a 5 horsepower motor can actually supply

Accepted Answer

A)  6 hp. 
B)  5.5 hp. 
C)  5.2 hp. 
D)  12 hp. 
E)  none of the above 
A)  6 hp. 
B)  5.5 hp. 
C)  5.2 hp. 
D)  12 hp. 
E)  none of the above

Question 11

The performance of the resistance -start, induction -run motor and the capacitor -start, induction -run motor is basically identical.

Accepted Answer

A) True 
 B)False

Question 12

When approximating the characteristics of a three -phase induction motor, which is not a rule of thumb?

Accepted Answer

A)  The full load current is equal to a constant times the ratio of input power to stator voltage. 
B)  The starting current is roughly 6 times the full load current. 
C)  The no load current is roughly 0.3 times the full load current. 
D)  The rotor inductive reactance is equal to the rotor resistance in the stalled condition. 
A)  The full load current is equal to a constant times the ratio of input power to stator voltage. 
B)  The starting current is roughly 6 times the full load current. 
C)  The no load current is roughly 0.3 times the full load current. 
D)  The rotor inductive reactance is equal to the rotor resistance in the stalled condition.

Question 13

Solid state devices like the H -bridge eliminate shoot -through.

Accepted Answer

A) True 
 B)False

Question 14

AC power to the motor creates the magnetic field in the rotating assembly by current flow rather than induction.

Accepted Answer

A) True 
 B)False

Question 15

In a system with a lagging power factor, the phase of current lags the phase of the voltage.

Accepted Answer

A) True 
 B)False

Question 16

The number of poles set the speed of the motor; the more poles the higher the speed.

Accepted Answer

A) True 
 B)False

Question 17

Match the portion of the curve t o motor operation.
  
-Between rated torque and minimum torque

Accepted Answer

A)  Stalls 
B)  Normal operating range 
C)  Provides breakaway torque 
D)  Provides the starting torque 
E)  Operates temporari 
A)  Stalls 
B)  Normal operating range 
C)  Provides breakaway torque 
D)  Provides the starting torque 
E)  Operates temporari

Question 18

The input power supply to the series motor is equal to the voltage drop across the field winding plus the voltage drop across the armature resistance plus cemf.

Accepted Answer

A) True 
 B)False

Question 19

The magnetic strength of an electromagnetic cannot be increased beyond the point of saturation.

Accepted Answer

A) True 
 B)False

Question 20

Match the following.
-Filter

Accepted Answer

A)  Usually a thyristor bridge 
B)  Controls the phase of the current 
C)  Consists of solid-state switches 
D)  Provides signals for frequency control 
E)  Smooths regulated DC voltage 
A)  Usually a thyristor bridge 
B)  Controls the phase of the current 
C)  Consists of solid-state switches 
D)  Provides signals for frequency control 
E)  Smooths regulated DC voltage

Which of the following is not an advantage of a three -phase motor over a single -phase motor?

The speed of the compound motors can be controlled with an adjustment to the shunt winding current.

Flux lines exit from the north pole and re -enter through the south pole.

Match the overload block with its operation. -Bimetallic

Match the overload block with its operation. -Eutectic

In a squirrel cage three -phase induction motor, the rotor resistance is equal to the rotor inductive reactance at the pull -out point.

Which of the following is not a component of a DC motor starter?

AC motors are available as single phase motors, typically less than 3 hp.

If brushes wear out, they can damage the commutator.

For a motor with service factor of 1.2, a 5 horsepower motor can actually supply

The performance of the resistance -start, induction -run motor and the capacitor -start, induction -run motor is basically identical.

When approximating the characteristics of a three -phase induction motor, which is not a rule of thumb?

Solid state devices like the H -bridge eliminate shoot -through.

AC power to the motor creates the magnetic field in the rotating assembly by current flow rather than induction.

In a system with a lagging power factor, the phase of current lags the phase of the voltage.

The number of poles set the speed of the motor; the more poles the higher the speed.

Match the portion of the curve t o motor operation. -Between rated torque and minimum torque

The input power supply to the series motor is equal to the voltage drop across the field winding plus the voltage drop across the armature resistance plus cemf.

The magnetic strength of an electromagnetic cannot be increased beyond the point of saturation.

Match the following. -Filter

Introduction to Industrial Control Systems, Discrete Control Input and Output Devices

Solidstate Devices in Industrial Applications, Operational Amplifiers and Linear ICS

SCRS, Triacs, Other Thryristors, Discrete Automation Sensors and Devices

Analog Processes Control Devices, Sensors and Safety

Special Purpose Motor, Control Devices and Programmable Logic Controllers

Embedded Microcontrollers, Open and Closed Loop Process Control

Industrial Robots, Automation Systems and Data Communication Between Intelligent Machines

Filters

Exam 5: DC Motors, Control Circuits, AC Motors and Variable Speed Drives

Which of the following is not an advantage of a three -phase motor over a single -phase motor?

The speed of the compound motors can be controlled with an adjustment to the shunt winding current.

Flux lines exit from the north pole and re -enter through the south pole.

Match the overload block with its operation. -Bimetallic

Match the overload block with its operation. -Eutectic

In a squirrel cage three -phase induction motor, the rotor resistance is equal to the rotor inductive reactance at the pull -out point.

Which of the following is not a component of a DC motor starter?

AC motors are available as single phase motors, typically less than 3 hp.

If brushes wear out, they can damage the commutator.

For a motor with service factor of 1.2, a 5 horsepower motor can actually supply

The performance of the resistance -start, induction -run motor and the capacitor -start, induction -run motor is basically identical.

When approximating the characteristics of a three -phase induction motor, which is not a rule of thumb?

Solid state devices like the H -bridge eliminate shoot -through.

AC power to the motor creates the magnetic field in the rotating assembly by current flow rather than induction.

In a system with a lagging power factor, the phase of current lags the phase of the voltage.

The number of poles set the speed of the motor; the more poles the higher the speed.

Match the portion of the curve t o motor operation. -Between rated torque and minimum torque

The input power supply to the series motor is equal to the voltage drop across the field winding plus the voltage drop across the armature resistance plus cemf.

The magnetic strength of an electromagnetic cannot be increased beyond the point of saturation.

Match the following. -Filter

Introduction to Industrial Control Systems, Discrete Control Input and Output Devices

Solidstate Devices in Industrial Applications, Operational Amplifiers and Linear ICS

SCRS, Triacs, Other Thryristors, Discrete Automation Sensors and Devices

Analog Processes Control Devices, Sensors and Safety

Special Purpose Motor, Control Devices and Programmable Logic Controllers

Embedded Microcontrollers, Open and Closed Loop Process Control

Industrial Robots, Automation Systems and Data Communication Between Intelligent Machines

Filters