Font size
WorksheetsEM202 Revision for Final Exam
Total questions: 81
Worksheet time: 41mins
It is an AC motor wherein, at steady state, the rotation of the shaft is synchronized with the frequency of the supplied current.
Pump Motor
Induction Motor
Synchronous Motor
DC Motor
It is the stationary parts of an AC motor.
Rotor
Stator
Commutator
Bearing
The rotating part of an AC motor.
Stator
Stator Winding
Rotor
Frame
What is the electric current used in an AC motor?
Direct Current
Alternating Current
Magnetic Field
None of the above
What is the electric current used in a DC motor?
Starting Current
Direct Current
Alternating Current
Surge Current
It is a small generator placed in the rotor, which provides excitation power for synchronous motor.
Stator Winding
Field Winding
Exciter
Shaft
The rotor winding in synchronous is excited by.
DC source
AC source
AB source
DB source
The stator winding of synchronous motor is excited by.
AC source
DC source
Battery
None of the above
It uses permanent magnets in the steel rotor to create a constant magnetic flux.
Reluctance Synchronous ac motor
Induction motor
Permanent Magnet synchronous motor
none of the above
It provide DC supply to the rotor to generate a magnetic field. It has both stators winding as well as rotor winding.
Induction motor
DC Excited synchronous motor
Single-phase ac motor
Three-phase induction motor
The Synchronous Motors are highly efficient machines, and their efficiency is much greater than induction motors.
True
False
The Synchronous motors use brushless Exciter which decreases the maintenance problem.
False
True
These motors are called universal motors since they are operable both on AC and DC.
Induction motor
AC Commutator motor
Three-phase motor
Single-phase motor
What does RMF mean?
Rotating Magnetic Field
Rotating Magnesium Field
Rotor Magnet Flow
Rotating Mega Field
What does rpm mean?
revolution per millisecond
revolution per second
revolution per minute
none of the above
It is connected to a power source and becomes an electromagnet when the current is applied.
Stator
Stator Winding
Rotor
End Cap
It extends outside the motor casing allowing connection to a mechanical system to transmit the rotational power.
Shaft
Rotor
Stator
Bearing
It holds the motor shaft in place and rotate the rotor smoothly.
Frame
Terminal
Bearing
Rotor
It protects the internal parts of the motor from water and other environmental elements.
Enclosure
End cap
Terminal
Stator
The motor that runs both rotor and RMF at constant speed is?
Induction Motor
Asynchronous Motor
Synchronous Motor
Three-phase Induction Motor
Also known as asynchronous motors because they always run slower than synchronous speed.
Induction motor
Synchronous Motor
Self-Excited DC Motor
none of the above
It is a DC motors where the field winding is connected either in series or parallel to the armature winding.
Self-Excited DC Motor
Non-Self Excited DC Motor
Synchronous Motor
Permanent Magnet DC Motor
It is to commute or relay the supply current from the main terminals to the armature winding through the brushes of the DC motor.
Commutator
Field winding
Armature Winding
Stator Winding
Used to connect the current from external terminals to the rotating commutator.
Brush
Rotor
Stator
Shaft
Protects the fan and direct the ambient air to the frame of the motor.
Fan
Frame
Protective Cover
End cap
Identify the picture that was given.
Terminal
Coils
Prottective Cover
Nameplate
Fed to the rotor to produce a DC field to run in synchronization with the field of the stator.
DC excitation
Ac excitation
Three-phase supply
Single-phase supply
This is not a non-excited synchronous motor.
Reluctance motor
Hysteresis motor
Permanent Magnet motor
Direct current excited motor
The single-phase induction motor is not self-starting.
True
False
These induction motors are self-starting and use no capacitor, start winding, centrifugal switch, or another starting device.
Three-phase induction motor
Single-phase induction motor
Synchronous motor
Universal motor
Identify the given picture.
Rotor
Stator
Bearing
Shaft
Identify the given picture.
Stator
Stator winding
Rotor
Frame
Identify the given picture.
Rotor
Shaft
Bearing
Stator
Identify the given picture.
Rotor
Shaft
Bearing
End Cap
Identify what type of rotor shown on the image.
Squirrel cage rotor
Slip-ring rotor
Cat gage rotor
Sleep-ring rotor
Identify what type of rotor shown on the image.
Sleep-ring rotor
Squirrel cage rotor
Slip-ring rotor
Sheep cage rotor
Identify the name of the image provided.
Enclosure
End cap
Shaft
Rotor
Identify the name of the image provided.
Rotor
Stator
Commutator
End cap
Identify the given image
shaft
bearing
stator
end cap
Identify the given image.
Frame
Shaft
Motor Terminal
Rotor
It is made by connecting one end of each of the three-phase windings together.
Delta Connection
Star Connection
Star-Delta Connection
Forward-Reverse
It is made by connecting the starting to the finishing ends of the phases or the starting end of the first phase is connected to the finishing end of the second phase and so on (for all three phase) forming a close triangle.
Star-Delta Connection
Star Connection
Delta Connection
Alpha Connection
The voltage measured across a single winding of a three-phase star connection is?
Phase current
Phase voltage
Phase power
Line voltage
The voltage measured between the lines of a three-phase delta connection is known as?
Line voltage
Phase voltage
Line current
Phase current
What does DOL mean in motor control?
Dive-On-Line
Direct-On-Line
DC-On-Line
Delta-On-Line
In three-phase star connection supply the line voltage is equal to phase voltage.
line voltage = phase voltage
False
True
In three-phase balanced Delta connection, the three-line currents are equal in magnitude and differ in phase by 120°.
True
False
The formula for line current in three-phase delta connection
IL = √3 IPh
True
False
In three-phase balanced star connection, the Neutral current is equal to 0.
True
False
In a delta connection, line voltage and phase voltage are the same.
True
False
Identify the component given.
Magnetic Contactor
Overload Relay
Push button Switch
Selector Switch
Identify the component given.
Thermal Overload relay
Magnetic Contactor
Selector Switch
None of the above
Selector Switch
Push Button Switch
Thermal Overload relay
Magnetic Contactor
Identify the component given.
Selector switch
Push Button switch
Two-way switch
AC switch
AC switch
Push Button switch
Selector switch
Three-way switch
It is an electrically controlled switch used for switching an electrical power circuit.
Thermal Overload relay
Magnetic contactor
PVC Box Enclosure
None of the above
It is a relay designed to protect electrical systems from overheated conditions specially for motor.
Magnetic Contactor
Thermal overload
Push button switch
Selector Switch
It is designed for indoor use to house pushbuttons, selector switches, and pilot lights.
Magnetic Contactor
Thermal Overload relay
Switch box enclosure
Indicating lamp
Three 24 Ω resistors are connected is star (Y) and is connected to a three-phase power supply with a 240V phase voltage. Calculate the load current.
Formula: ILoad = VLoad / R
15A
10A
20A
100A
Three 24 Ω resistors are connected is star (Y) and is connected to a three-phase power supply with a 240V phase voltage. Calculate the line voltage.
Formula: VL = √3 VLoad
415V
400V
380V
230V
Three 24 Ω resistors are connected is star (Y) and is connected to a three-phase power supply with a 240V phase voltage. Calculate the neutral current.
10 A
1 A
0 A
2 A
Three resistors each has 41.5 Ω are connected in Delta (∆) to 415V three-phase power supply. Find the value of load current.
Formula: I Load = VLoad / R
100 A
10 A
20 A
25 A
Three resistors each has 41.5 Ω are connected in Delta (∆) to 415V three-phase power supply. Find the value of line current.
Formula = IL = √3 ILoad
17.3 A
15.3 A
25 A
30 A
It is an injury caused by electrical current passing though the human body.
Electrical conversion
Electrical Shock
Electrical Surge
Overvoltage
What devices need to be installed in a motor for safety measures against accidents or fire caused by overheating.
Thermal overload
Magnetic contactor
Push Button switch
Selector switch
Who is allowed to install, operate, or even repair the motor – to run it.
Qualified Technician
Technician
Rigger
Plumber
Which area where you are not allowed to use an electric motor?
Flammable area
Dry location
Workshop area
Industrial area
Identify the image given.
Magnetic contactor coil
Selector switch
Push button switch
Thermal overload
What does rpm mean?
revolution per mile
revolution per mil
revolution per minute
none of the above
In three-phase balanced star connection, the Neutral current is equal to 0 A.
True
False
In a delta connection, line voltage and phase voltage are not the same value.
True
False
In the open circuit test of a three-phase motor winding, when an ohmmeter reading is infinity, mean the coil is closed.
True
False
In the short circuit test of a three-phase motor winding, when an ohmmeter reading is zero or nearly zero ohms, it means the coil is shorted.
True
False
It is made by connecting the starting to the finishing ends of the phases or the starting end of the first phase is connected to the finishing end of the second phase and so on (for all three phase) forming a close triangle.
Star connection
Delta connection
Forward-Reverse
Charlie connection
The motor that runs at synchronous constant speed is known as?
Synchronous motor
Induction motor
Single-phase motor
Three-phase motor
In delta-connection motor speed is high because each phase gets the total of the line voltage.
True
False
In a delta connection, line voltage and phase voltage are not the same value.
True
False
For high starting torque, a delta connection is required.
True
False
In star-connection motor speed is high due to 1/√3 of the voltage.
True
False
Identify the circuit given.
Direct-On-line
Forward-reverse
Star-Delta
none of the above
In a three-phase Induction motor, one terminal from each winding is connected to a common point, and the remaining three terminals are connected to the external circuit.
Star connection
Delta connection
Charlie connection
Beta connection
