Application of DC Series Motor

Application of DC Series Motor
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1 Answer

Answer :

1. Electric traction

2. Cranes,

3. Passenger elevators,

4. Continuous conveyors,

5. Grinders,

6. Polishers,


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Related questions

DC series motor should never be started at no-load. Justify.

Description : DC series motor should never be started at no-load. Justify. 

Last Answer : At no load the field current (which is also the armature current) is very small and hence the useful air-gap field flux. Also the torque is very small.  As N ∝ 1/Ф the speed rises to ... on the rotating parts they may get damaged. Hence DC series motor should never be started on no-load.

With the help of neat diagrams,explain the following methods of speed control in DC series motor. i) Field diverter method. ii) Armature diverter method.

Description : With the help of neat diagrams,explain the following methods of speed control in DC series motor. i) Field diverter method. ii) Armature diverter method.

Last Answer : (i) Field diverter method: - Resistance connected in parallel with field winding -By adjusting this resistance current can by diverted from field winding -Thus field current decreases and the speed can be ... decreased, the flux must increase and hence speed is decreased than the rated speed.

A cumulative dc compound motor runs at 1500 rpm. on full load. If its series field is short-circuited, its speed

Description : A cumulative dc compound motor runs at 1500 rpm. on full load. If its series field is short-circuited, its speed  (1) becomes zero (2) remains unchanged (3) increases (4) decreases

Last Answer : Increases. As it's cumulative compound motor, both series and shunt field both assist each other. If series field is short circuited, the overall field strength will decrease and atop of that ... speed is inversely proportional to field strength.  So, the speed will increase overall.

Why a dc series motor has a high starting torque?

Description : Why a dc series motor has a high starting torque?

Last Answer : motor

Which of the following statements represents an application of a silicon controlled rectifier? A. To provide DC power for a main propulsion motor. B. For use as a voltage reference diode. C. For sensing flame in an automated burner. D. To eliminate power supply hum.

Description : Which of the following statements represents an application of a silicon controlled rectifier? A. To provide DC power for a main propulsion motor. B. For use as a voltage reference diode. C. For sensing flame in an automated burner. D. To eliminate power supply hum.

Last Answer : Answer: A

A DC shunt motor has rated rpm of 480. Certain industrial application requires this motor to run at 540 rpm

Description : A DC shunt motor has rated rpm of 480. Certain industrial application requires this motor to run at 540 rpm for some time. Which speed control will be desirable? A) Ward Leonard control B) Armature ... ) Field resistance control D) It is not possible to run the motor at more than the rated rpm 

Last Answer : A DC shunt motor has rated rpm of 480. Certain industrial application requires this motor to run at 540 rpm for some time. Which speed control will be desirable? A) Ward Leonard control B) Armature ... Field resistance control D) It is not possible to run the motor at more than the rated rpm 

Why is it dangerous yo supply power to an unloaded series connected dc motor?

Description : Why is it dangerous yo supply power to an unloaded series connected dc motor?

Last Answer : Need answer

A series wound DC motor has its armature and field connected in series with a resistor. When the motor is disconnected from its power supply, this motor will exemplify __________. A. the proper connections for across the line starting B. the proper connections for an automatic strip heater C. a reversing controller circuit D. dynamic braking

Description : A series wound DC motor has its armature and field connected in series with a resistor. When the motor is disconnected from its power supply, this motor will exemplify __________. A. the ... the proper connections for an automatic strip heater C. a reversing controller circuit D. dynamic braking

Last Answer : Answer: D

The direction of rotation of a DC propulsion motor can be reversed by __________. A. reversing the field connections B. reversing the field and the armature connections C. wiring the field and armature in parallel D. wiring the field and armature in series

Description : The direction of rotation of a DC propulsion motor can be reversed by __________. A. reversing the field connections B. reversing the field and the armature connections C. wiring the field and armature in parallel D. wiring the field and armature in series

Last Answer : Answer: A

A dc cumulatively compounded motor delivers rated load torque at rated speed. If series field is short circuited, then the armature current and speed will a) Both increases b) Both decreases c) Increases and decreases d) Decreases and increases

Description : A dc cumulatively compounded motor delivers rated load torque at rated speed. If series field is short circuited, then the armature current and speed will a) Both increases b) Both decreases c) Increases and decreases d) Decreases and increases

Last Answer : Ans: Both increases

Regenerative braking (A) Can be used for stopping a motor. (B) Cannot be easily applied to DC series motors. (C) Can be easily applied to DC shunt motors (D) Cannot be used when motor load has overhauling characteristics.

Description : Regenerative braking (A) Can be used for stopping a motor. (B) Cannot be easily applied to DC series motors. (C) Can be easily applied to DC shunt motors (D) Cannot be used when motor load has overhauling characteristics.

Last Answer : Ans: B Because reversal of Ia would also mean reversal of field and hence of Eb

As compared to shunt and compound DC motors, the series DC motor will have the highest torque because of its comparatively ____________ at the start. (A) Lower armature resistance. (B) Stronger series field. (C) Fewer series turns. (D) Larger armature current.

Description : As compared to shunt and compound DC motors, the series DC motor will have the highest torque because of its comparatively ____________ at the start. (A) Lower armature resistance. (B) Stronger series field. (C) Fewer series turns. (D) Larger armature current.

Last Answer : (D) Larger armature current.

The torque, in a _____________is proportional to the square of the armature current (A) DC shunt motor (B) stepper motor (C) 2-phase servomotor (D) DC series motor

Description : The torque, in a _____________is proportional to the square of the armature current (A) DC shunt motor (B) stepper motor (C) 2-phase servomotor (D) DC series motor

Last Answer : (D) DC series motor

The speed-torque characteristics of a DC series motor are approximately similar to those of the _________motor. (A) universal (B) synchronous (C) DC shunt (D) two-phase

Description : The speed-torque characteristics of a DC series motor are approximately similar to those of the _________motor. (A) universal (B) synchronous (C) DC shunt (D) two-phase

Last Answer : Ans: A Universal motor has same characteristics as DC series motor and also known as an a.c series motor.

The most suitable servomotor for low power applications is (A) a dc series motor. (B) a dc shunt motor. (C) an ac two-phase induction motor. (D) an ac series motor.

Description : The most suitable servomotor for low power applications is (A) a dc series motor. (B) a dc shunt motor. (C) an ac two-phase induction motor. (D) an ac series motor.

Last Answer : (B) a dc shunt motor.

State the modification to be done in dc series motor to work satisfactorily as ac series motor. State applications of ac series motor.

Description : State the modification to be done in dc series motor to work satisfactorily as ac series motor. State applications of ac series motor.

Last Answer : Modifications are necessary in a dc series motor so that it operates satisfactorily on ac supply. The modifications are as follows:  1) AC series motor is built with a few field turns as ... and grinders 5) High speed vacuum cleaners 6) Sewing machines 7) Food processors 8) Drilling machine 

Brake test on DC series motor

Description : Brake test on DC series motor

Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }

"DC series motor is used for traction purpose." Justify your answer with any six characteristics.

Description : "DC series motor is used for traction purpose." Justify your answer with any six characteristics.

Last Answer : Due To Following Reasons DC Series Motor Is Used For Traction Purpose:- 1. DC Series motor robust in construction and capable to withstand against continuous vibration. 2. DC series motor weight is 1. ... . 12. Torque obtained by DC series motor is smooth and uniform, so it improves riding quality

Describe the reason of using dc series motor for electric trains.

Description : Describe the reason of using dc series motor for electric trains.

Last Answer : Electric trains require an inverse torque speed characteristics for proper operation. That is a higher torque is required at start (when speed is nil or low) and as the train picks up ... torque - speed characteristics of DC series motors match, these motors are suitable for electric trains

A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated

Description : A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to  (A) 0.75 p.u (B) 0.5 p.u (C) 0.25 p.u (D) 0.125 p.u

Last Answer : A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.5 p.u

In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at

Description : In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at half full load in N -m is :

Last Answer : In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at half full load in N -m is : 0.075

Limitation and application of High Voltage DC (HVDC)

Description : Limitation and application of High Voltage DC (HVDC)

Last Answer : Limitation and application of High Voltage DC (HVDC) :  Limitation:- 1) It is difficult to step up and step down DC voltage like AC voltage. 2) Special cooling ... conventional/non-conventional) 12) Increasing existing grid utilization. 13) Interconnection of different grids or networks

Compare AC & DC track circuits on i) Length of circuit ii) Application iii) Effect of stray currents. iv) Maintenance

Description : Compare AC & DC track circuits on i) Length of circuit ii) Application iii) Effect of stray currents. iv) Maintenance

Last Answer : Ans: i) Length of circuit - a) AC track circuit is having long length upto 3 to 5 km b) DC track circuit is having short length  ii)Application -a) AC track circuit is used ... ) Maintenance - a) AC track circuit has easier and cheaper maintenance b) DC track circuit has complicated maintenance 

Which of the following generators is used for DC arc welding application ?

Description :  Which of the following generators is used for DC arc welding application ? (A) Series generator (B) Shunt generator (C) Differential compound generator (D) Over -compound generator

Last Answer : A

A supply of 24 V DC is applied across a circuit which consist of three resistors connected in parallel R1= 1.2KΩ, R2= 560 Ω, R3= 2.1Ω and a fourth resistor of 7.8 Ω connected in series with the parallel group. Determine the current, voltage and power across each resistor

Last Answer : Req= (1/1200 +1/560 + 1/2.1)^-1        = 2.1 ohms RT= 2.1 + 7.8      = 9.9 ohms IT = V/R = 24/9.9                = 2.4 A Veq= R I =  2.1 2 ... 7.8         = 12.096 w                 = 44.928 w _________________________________________ By: Ellis-Junior Kamatjipose [email protected]

A 35 V dc supply is connected across a resistance of 600 ohm in series with an unknown resistance R. A

Description : A 35 V dc supply is connected across a resistance of 600 ohm in series with an unknown resistance R. A voltmeter having a resistance of 1.2 kOhm is connected across 600 ohm resistances and reads 5 V. The value of resistance R shall be:

Last Answer : A 35 V dc supply is connected across a resistance of 600 ohm in series with an unknown resistance R. A voltmeter having a resistance of 1.2 kOhm is connected across 600 ohm resistances and reads 5 V. The value of resistance R shall be: 2.4 kOhm

We connected a 35V dc supply to a resistance of 600 Ohm in series with an unknown resistance

Description : We connected a 35V dc supply to a resistance of 600 Ohm in series with an unknown resistance R.A. voltmeter having a resistance of 1.2 kOhm is connected across 600 Ohm resistance and read 5v. The value of resistance R will be

Last Answer : We connected a 35V dc supply to a resistance of 600 Ohm in series with an unknown resistance R.A. voltmeter having a resistance of 1.2 kOhm is connected across 600 Ohm resistance and read 5v. The value of resistance R will be 2.4 kOhm

If field current is decreased in shunt dc motor, the speed of the motor

Description : If field current is decreased in shunt dc motor, the speed of the motor (a) remains same. (b) increases. (c) decreases. (d) none of the above.

Last Answer : increases

What would happen if a DC motor was supplied with AC ?

Description : What would happen if a DC motor was supplied with AC ?

Last Answer : With three phase induction motor, humming and not rotate, but if single phase universal motor like air blower, home mixture, motor run on constant speed..speed variation not possible...

State the function of following parts of DC motor : i) Yoke ii) Poles iii) Field winding iv) Commutator.

Description : State the function of following parts of DC motor : i) Yoke ii) Poles iii) Field winding iv) Commutator. 

Last Answer : Function : i) Yoke: The yoke serves the following two purposes. i) It supports the other components such as poles and provides mechanical protection for whole machine. ii) It forms a part of ... one pole to another and thus to help the motor to develop a continuous and unidirectional torque  

What is back emf in DC motor? Explain its significance.

Last Answer : Back emf: When the armature of DC motor rotates under the fixed magnetic field and cuts it, by Faraday's law an emf is induced in them. The induced emf acts in opposite direction to the ... the flow of armature current i.e. it automatically changes the armature current to meet load requirements. 

State the principle of operation of a dc motor.

Last Answer : Principle of operation of a dc motor: When a current carrying conductor is placed in a magnetic field, the conductor experiences the mechanical force. The magnitude of force is given by  F = BIL newton  where F – Force , B – Maximum flux density , I – Current , L – Active length of conductor

Give the two functions of yoke in DC motor.

Description : Give the two functions of yoke in DC motor. 

Last Answer : Functions of yoke in DC motor: 1) Provides mechanical support for poles. 2) Acts as protecting cover for machine. 3) Provides path for magnetic flux.

State any two applications of brushless DC motor.

Description : State any two applications of brushless DC motor. 

Last Answer : 1) Synthetic fibre drawing works.  2) Turn table drives in record players.  3) Spindle drives in hard disk circuits.  4) Computer peripheral equipments as plotters etc. 5) Gyroscope motors.  6) Biomedical machines as heart pumps. 

With the help of necessary sketch, explain in brief the working of brushless DC motor.

Description : With the help of necessary sketch, explain in brief the working of brushless DC motor. 

Last Answer : Constructional Diagram of Brushless DC Motor: Working of brushless DC motor: The brushless DC motor is the combination of a permanent excited synchronous motor and a frequency ... Suitable PWM techniques allow regenerative breaking, which increases dynamic and efficiency of the drive. 

List the various losses on a DC Motor.

Description : List the various losses on a DC Motor. 

Last Answer : The various losses on a DC Motor: 1) Winding losses (Copper losses): i) Armature winding losses ii) Shunt field losses iii) Series field losses 2) Core losses (iron losses): 3) Brush contact losses: 4) Windage and frictional (Mechanical losses):

A separately excited dc motor operating in first quadrant is fed from 3-phase semi -converter free -wheeling

Description : A separately excited dc motor operating in first quadrant is fed from 3-phase semi -converter free -wheeling diode is open circuited, then the motor :  (A) can be operated in first quadrant (B) ... in first & second quadrants (C) can be operated in first & fourth quadrants (D) cannot be operated

Last Answer : A separately excited dc motor operating in first quadrant is fed from 3-phase semi -converter free -wheeling diode is open circuited, then the motor : can be operated in first & fourth quadrants

In a DC motor, it is important to place the brushes along ______

Description : In a DC motor, it is important to place the brushes along ______ A) Magnetic Neutral Axis B) Normal Geometric Axis C) Nominal Geometric Axis D) None of these

Last Answer : In a DC motor, it is important to place the brushes along Magnetic Neutral Axis

In a 4-pole wave winding connected dc motor, the cross-magnetizing AT/pole for a brush shift of θ radians

Description : In a 4-pole wave winding connected dc motor, the cross-magnetizing AT/pole for a brush shift of θ radians (A) Armature amp-conductors × (θ/360o) (B) Armature amp-turns × (θ/360o) (C) Armature amp-conductors × (1/4 - θ/360o) (D) Armature amp-conductors × (1/8 - θ/360o)

Last Answer : In a 4-pole wave winding connected dc motor, the cross-magnetizing AT/pole for a brush shift of θ radians Armature amp-conductors × (1/8 - θ/360o)

In a differentially compounded dc motor

Description : In a differentially compounded dc motor (A) the speed is constant as the torque increases (B) the speed falls non-linearly as the torque increases (C) the speed increases non-linearly as the torque increases (D) the flux increases as the load increases

Last Answer : In a differentially compounded dc motor the speed increases non-linearly as the torque increases

A large dc motor is required to control the speed of the blower from a 3 -phase ac source. The suitable ac to ...

Description : A large dc motor is required to control the speed of the blower from a 3 -phase ac source. The suitable ac to dc converter is, 3 -phase (a) Fully controlled bridge converter ( ... bridge converter with freewheeling diode (c) Half controlled bridge converter (d) Converter pair in sequence control

Last Answer : a fullu control

The dc motor used for intermittent high torque loads is

Description : The dc motor used for intermittent high torque loads is  (1) dc series motor (2) dc shunt motor (3) differential compound motor (4) cumulative compound motor

Last Answer : 4 cumulative compound motor

A separately excited dc motor is required to be controlled, from a 3-phase supply, for its operation in the first...

Description : A separately excited dc motor is required to be controlled, from a 3-phase supply, for its operation in the first quadrant only. The most preferred converter would be  (a) 3-phase fully controlled ... converter with free wheel diode (c) 3-phase dual converter (d) 3-phase half wave converter 

Last Answer : A

Armature shunting method of speed control of dc shunt motor is preferred over annature resistance method...

Description : Armature shunting method of speed control of dc shunt motor is preferred over annature resistance method due to:  (1) Better speed regulation (2) Less loss in external resistance (3) Simplicity in control circuit (4) Reduced cost of controller

Last Answer : Armature shunting method of speed control of dc shunt motor is preferred over annature resistance method due to: Better speed regulation.

What is the order of the characteristic equation of an armature controlled DC motor?

Description : What is the order of the characteristic equation of an armature controlled DC motor?  (A) First order equation (B) Second order equation (C) Zero order equation (D) Third order equation 

Last Answer : third order

What is the principle of DC motor?

Description : What is the principle of DC motor?

Last Answer : principle

Use of dc motor

Last Answer : There are three types of self excited DC motor 1. series wound 2. shunt wound 3, compound wound 1.Applications of DC series motor are : DC ... DC compound motor is use for punches. These are some applications of DC compound motor.

What's is the self excited dc motor?

Last Answer : Self excited Dc motor have same source of power to armature and field winding

Application of Universal Motor

Description : Application of Universal Motor

Last Answer : Application of Universal Motor :  1) Mixer 2) Food processor 3) Heavy duty machine tools 4) Grinder 5) Vacuum cleaners 6) Refrigerators 7) Driving sewing machines 8) Electric Shavers ... ) Small Fans 11) Cloth washing machine 12) portable tools like blowers, drilling machine, polishers etc