search
person

1 Answer

If the capacitor of a single-phase motor is short-circuited the motor will not start.

thumb_up_alt 0 like thumb_down_alt 0 dislike

Related questions

Answer : In a capacitor start single-phase motor, when capacitor is replaced by a resistance motor will continue to run in same direction.

Answer : In case one phase of a three-phase synchronous motor is short-circuited the motor will not start.

Answer : In capacitor start single-phase motors current in the starting winding leads the voltage.

Description : A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will?

Answer : A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will not start at all.

Answer : A single-phase induction motor is inherently non-self-starting with low torque.

Answer : The power factor of a single-phase induction motor is usually lagging.

Answer : In a shaded pole single-phase motor, the revolving field is produced by the use of shading coils.

Answer : The rotor developed by a single-phase motor at starting is zero.

Answer : The capacitors used in single-phase capacitor motors have no polarity marking.

Answer : In a capacitor start motor, the phase displacement between starting and running winding can be nearly 90°.

Description : Why is a capacitor used in a single phase motor and not in three phase motor ?

Answer : In 1-phase induction motor capacitor work is generate the auxiliary winding current than excite the main winding to rotor starts rotate. After rotor start rotating about 75% of their speed than auxiliary ... emf to start the motor.so,in 3-phase induction motor is self start induction motor.

Description : Explain the working of a single phase capacitor start induction motor. 

Answer : Single phase capacitor start induction motor https://youtu.be/31lvvzU5Puc

Answer : If starting winding of a single-phase induction motor is left in the circuit, it will draw excessive current and overheat.

Answer : In a two value capacitor motor, the capacitor used for running purposes is paper spaced oil filled type.

Answer : The value of starting capacitor of a fractional horse power motor will be 300 uF .

Description : In a single-phase induction motor, the operating direction is determined by the ________ A) Rotor B) Stator C) Starting circuit D) None of these

Answer : In a single-phase induction motor, the operating direction is determined by the Starting circuit

Description : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ (A) directly proportional to α and Φ (B) ... proportional to α and inversely proportional to Φ (D) directly proportional to Φ and inversely proportional to α

Answer : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ directly proportional to α and inversely proportional to Φ

Description : In a single-phase induction motor when the rotor is stationary and voltage is applied to the stator, then (A) the flux is constant (B) the flux first decreases and then increases in ... increases and decreases in the opposite direction with the same magnitude (D) current flows through the rotor

Answer : In a single-phase induction motor when the rotor is stationary and voltage is applied to the stator, then the flux first decreases and then increases in the same direction

Answer : The starting winding of a single-phase motor is placed in stator.

Description : The secondary of a current transformer is always short-circuited under operating conditions because it?

Answer : The secondary of a current transformer is always short-circuited under operating conditions because it avoids core saturation and high voltage induction.

Answer : If the centrifugal switch of a two-value capacitor motor using two capacitors fails to open then Electrolytic capacitor will, in all probability, suffer break down.

Answer : To reverse the direction of rotation of a capacitor start motor while it is running we should disconnect motor from the supply till it stops then reconnect it to supply with reversed connection of main or auxiliary winding.

Answer : Two-value capacitor motor finds increased application as compressor motor in small home air-conditioners because it has low starting as well as running currents at relatively high power factor.

Answer : In a ceiling fan employing capacitor run motor secondary winding surrounds the primary winding.

Description : Can we use the synchronous motor as the synchronous capacitor?

Answer : Yes, we can use the synchronous motor as the synchronous capacitor when the synchrnous motor is overexcited.

Description : A three phase slip ring induction motor is fed from the rotor side with stator winding short circuited stator is: (1) Slip frequency (2) Supply frequency (3) Frequency corresponding to rotor speed (4) Zero

Answer : A three phase slip ring induction motor is fed from the rotor side with stator winding short circuited stator is: Slip frequency

Answer : Single phase induction motor usually operates on 0.6 power factor lagging.

Description : The running winding of a single phase motor on testing with meggar is found to be ground. Most probable location of the ground will be?

Answer : The running winding of a single phase motor on testing with meggar is found to be ground. Most probable location of the ground will be at the slot edge where coil enters or comes out of the slot.

Answer : In a single phase motor the centrifugal switch disconnects auxiliary winding of the motor.

Answer : In a capacitor start and run motors the function of the running capacitor in series with the auxiliary winding is to improve power factor.

Description : Single-phase mid-point controlled rectifier with RL load

Answer : Single-phase mid-point controlled rectifier with RL load : The circuit configuration of single-phase midpoint controlled rectifier is shown in the figure. During positive half-cycle of ... some part of next positive half-cycle of voltage with reversed polarity can appear across load.

Description : Single-phase Midpoint controlled rectifier with Resistive load

Answer : Single-phase Midpoint controlled rectifier with Resistive load:  1) During positive half cycle of AC supply, a is positive with respect to b , this makes T1 forward biased and T2 is reverse ... voltage reverses the polarity and T2 is turned off. The operation is as shown in waveforms.

Description : When the firing angle a of a single-phase, fully controlled rectifier feeding constant direct current into a load is 30°, the displacement power factor of the rectifier is

Answer : When the firing angle a of a single-phase, fully controlled rectifier feeding constant direct current into a load is 30°, the displacement power factor of the rectifier is √3/2

Description : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that

Answer : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that the transformers should belong to the same vector group

Description : A 230 V, 50 Hz phase controlled single-phase full-controlled SCR bridge converter draws 15 A constant dc current. If the source inductance is 3 mH, the drop in dc output voltage is (A) 4.5 V (B) 6.75 V (C) 9 V (D) 13.5 V

Answer : A 230 V, 50 Hz phase controlled single-phase full-controlled SCR bridge converter draws 15 A constant dc current. If the source inductance is 3 mH, the drop in dc output voltage is 9 V

Description : In a 230 V, 50 Hz single-phase SCR bridge converter operating at a firing delay angle, α and with large R-L load, the input source current is (A) sinusoidal current (B) constant dc current (C) continuous rectangular pulses (D) alternating rectangular pulses

Answer : In a 230 V, 50 Hz single-phase SCR bridge converter operating at a firing delay angle, α and with large R-L load, the input source current is alternating rectangular pulses

Description : The sequence components of current of a single-phase load connected to a 3-phase system are (A) equal positive and negative sequence components (B) equal positive, negative and zero sequence components (C) vector sum of sequence currents is zero (D) algebraic sum of sequence currents is zero

Answer : The sequence components of current of a single-phase load connected to a 3-phase system are equal positive, negative and zero sequence components

Description : A 230 V/460 V single-phase transformer operating at 20 A and unity power factor has primary referred resistance of 0.2 Ω and reactance of 0.5 Ω. The approximate primary induced emf is (A) 216 V (B) 226 V (C) 234 V (D) 236 V

Answer : A 230 V/460 V single-phase transformer operating at 20 A and unity power factor has primary referred resistance of 0.2 Ω and reactance of 0.5 Ω. The approximate primary induced emf is 226 V

Description : In a single-phase transformer, the magnetizing current is (A) in phase with the no-load current (B) in quadrature with the no-load current (C) the product of no-load current and power factor (D) in phase with the flux in the core

Answer : In a single-phase transformer, the magnetizing current is in phase with the flux in the core

Answer : If the field winding of an unloaded salient pole synchronous motor is open circuited, the motor will stop.

Description : For a single phase capacitor start induction motor, which of the following statements is valid?  A) The capacitor is used for power factor improvement B) The direction of rotation can be ... rotation cannot be changed D) The direction of rotation can be changed by interchanging the supply terminals

Answer : For a single phase capacitor start induction motor, which of the following statements is valid?  A) The capacitor is used for power factor improvement B) The direction of rotation can be ... cannot be changed D) The direction of rotation can be changed by interchanging the supply terminals

Answer : If a single phase induction motor runs slower than normal, the most likely defect is worn bearings.

Description : The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be?

Answer : The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be 4.

Answer : In split-phase motor auxiliary winding is of thin wire placed at the top of the slots.

Answer : Direction of rotation of a split phase motor can be reversed by reversing the connection of either running winding or starting winding.

Answer : In a split phase motor the starting winding is connected through a centrifugal switch.

Answer : In a split phase motor, the running winding should have low resistance and high inductance.

Description : What happens to the capacitance if mica is inserted between the plates of an air capacitor? A) The capacitance increases B) The capacitance decreases C) The capacitance remains the same D) The capacitance becomes zero

Answer : What happens to the capacitance if mica is inserted between the plates of an air capacitor? A) The capacitance increases B) The capacitance decreases C) The capacitance remains the same D) The capacitance becomes zero

Answer : If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is 10°.

Description : State suitable single phase motor for following applications: (i) Table fan (ii) Mixers and Grinders

Answer : Application Suitable Single Phase Motor Table Fan 1) Capacitor split phase motor 2) Capacitor start capacitor run motor Mixers and Grinders 1) Universal motor 2) A.C. Series motor

← Prev Question Next Question →
editChoose topic
...