M
Mikeymike77
Hope this helps
1: When a capacitor start capacitor run motor reaches synchronous speed the centrifugal switch?
a: Leaves the start winding connected
b: Leaves only the run winding connected
c: Disconnected the supply to the start capacitor
d: Disconnects the run and start capacitors
2: For a three phase induction motor the differerence between the synchronous speed and rotor speed is the?
a: Slope
b: Slip
c: Skip
d: Slide
3: The rotational speed of a three phase, four pole synchronous motor operating at 50Hz supply.
a: 1500rpm
b: 3000rpm
c: 1000rpm
d: 750rpm
4: When a single phase capacitor start and capacitor run motor approaches its normal speed the centrifugal switch disconnects the?
a: Start capacitor
b: Run capacitor
c: Start winding
d: Run winding
5: The direction of a capacitor start motor can be reversed by?
a: Changing connections to both windings
b: Changing capacitor connections
c: Changing over the connections to the start or run winding
d: Changing connections to start & run winding
6: A single phase AC motor is constructed with?
a: Two magnetic fields in phase with each other
b: A magnetic field
c: Three magnetic fields
d: A secondary magnetic field out of phase with the primary field
7: A two pole induction motor runs at 925rpm when connected to the 50Hz supply. Calculate the slip?
a: 71%
b: 56.5%
c: 69%
d: 62%
8: A 3 phase 4 pole motor 50Hz induction motor has a slip of 4% the actual speed of the motor is?
a: 1500rpm
b: 1440rpm
c: 1400rpm
d: 1359rpm
9: Cage rotor induction motor are considered to be?
a: A variable speed machines
b: low speed
c: high speed
d: constant speed
10: Connections made to rotor windings on a 3 phase induction motor use?
a: Mutual inductance effect rotor & stator
b: Commutators and brushes
c: Capacitor link to rotor windings
d: Slip ring & brushes
11: The Thermal trip on a direct online starter (DOL) is to?
a: Provide magnetic overload protection
b: Provide thermal overload protection
c: Provide remote starting
d: Prevent motor over speed
12: A motor with a wound rotor has windings on?
a: Rotor only
b: Stator only
c: Stator & rotor
d: Communtator & field
13: When starting a 400v 3 phase cage rotor motor using star/delta starter, the voltage across each stator phase is?
a: 400v start 230v run
b: 133v start 230v run
c: 133v start 400v run
d: 230v start 400v run
14: A single loop of wire connected to the slip rings rotated in a magnetic field. Voltage
measured at slip rings will be?
a: D.C
b: A.C
c: undirectional
d: Intermittent
15: A capacitor start and run single phase induction motor runs as?
a: Quad phase motor
b: SIngle phase motor
c: Two phase motor
d: Three phase motor
16: Which of the following is suitable for starting a 3 phase rotor cage induction motor?
a: Auto transformer & rotor resistance
b: Rotor resistance and capacitor start
c: Auto transformer & star/delta
d: Capacitor start and star/delta
17: To reverse the rotation of a 3 Phase induction motor?
a: Disconnect the grey phase
b: Disconnect the brown phase
c: Change over any two phases
d: Change over three phases
1: When a capacitor start capacitor run motor reaches synchronous speed the centrifugal switch?
a: Leaves the start winding connected
b: Leaves only the run winding connected
c: Disconnected the supply to the start capacitor
d: Disconnects the run and start capacitors
2: For a three phase induction motor the differerence between the synchronous speed and rotor speed is the?
a: Slope
b: Slip
c: Skip
d: Slide
3: The rotational speed of a three phase, four pole synchronous motor operating at 50Hz supply.
a: 1500rpm
b: 3000rpm
c: 1000rpm
d: 750rpm
4: When a single phase capacitor start and capacitor run motor approaches its normal speed the centrifugal switch disconnects the?
a: Start capacitor
b: Run capacitor
c: Start winding
d: Run winding
5: The direction of a capacitor start motor can be reversed by?
a: Changing connections to both windings
b: Changing capacitor connections
c: Changing over the connections to the start or run winding
d: Changing connections to start & run winding
6: A single phase AC motor is constructed with?
a: Two magnetic fields in phase with each other
b: A magnetic field
c: Three magnetic fields
d: A secondary magnetic field out of phase with the primary field
7: A two pole induction motor runs at 925rpm when connected to the 50Hz supply. Calculate the slip?
a: 71%
b: 56.5%
c: 69%
d: 62%
8: A 3 phase 4 pole motor 50Hz induction motor has a slip of 4% the actual speed of the motor is?
a: 1500rpm
b: 1440rpm
c: 1400rpm
d: 1359rpm
9: Cage rotor induction motor are considered to be?
a: A variable speed machines
b: low speed
c: high speed
d: constant speed
10: Connections made to rotor windings on a 3 phase induction motor use?
a: Mutual inductance effect rotor & stator
b: Commutators and brushes
c: Capacitor link to rotor windings
d: Slip ring & brushes
11: The Thermal trip on a direct online starter (DOL) is to?
a: Provide magnetic overload protection
b: Provide thermal overload protection
c: Provide remote starting
d: Prevent motor over speed
12: A motor with a wound rotor has windings on?
a: Rotor only
b: Stator only
c: Stator & rotor
d: Communtator & field
13: When starting a 400v 3 phase cage rotor motor using star/delta starter, the voltage across each stator phase is?
a: 400v start 230v run
b: 133v start 230v run
c: 133v start 400v run
d: 230v start 400v run
14: A single loop of wire connected to the slip rings rotated in a magnetic field. Voltage
measured at slip rings will be?
a: D.C
b: A.C
c: undirectional
d: Intermittent
15: A capacitor start and run single phase induction motor runs as?
a: Quad phase motor
b: SIngle phase motor
c: Two phase motor
d: Three phase motor
16: Which of the following is suitable for starting a 3 phase rotor cage induction motor?
a: Auto transformer & rotor resistance
b: Rotor resistance and capacitor start
c: Auto transformer & star/delta
d: Capacitor start and star/delta
17: To reverse the rotation of a 3 Phase induction motor?
a: Disconnect the grey phase
b: Disconnect the brown phase
c: Change over any two phases
d: Change over three phases
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