search
person
Why a dc series motor has a high starting torque?

Related questions

Description : Why high starting torque is required?

Answer : Buses, trains, trolleys, hoists, cranes require high starting torque and therefore make use of D.C. series motor.

Description : Why does induction motor have high starting current?

Answer : In induction motor , the flux produce is quadrature to the applied voltage. Since when we are going to start motor , there is no flux present inside . So in order to lets say compensate it ... times of current to further increase flux. So that is reason for high starting current in induction motor

Answer : For the same H.P. rating and full load speed, following motor has poor starting torque differentially compounded.

Answer : Capacitor start motor has high torque in starting

Description : In a double squirrel cage induction motor, good starting torque is produced as (A) Large current flows through the outer high resistance winding. (B) Large current flows through the inner high ... the outer high resistance winding. (D) Large current flows through the inner low resistance winding.

Answer : In a double squirrel cage induction motor, good starting torque is produced as Large current flows through the outer high resistance winding.

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 :

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

Description : Why dc series motor should not be started at no load?

Description : DC motor gross torque example

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%; }

Description : What are the advantages of DC series motor?

Answer : In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.

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

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 

Description : Brake test on DC series motor

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%; }

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

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

Answer : The starting resistance of a D.C. motor is generally low.

Answer : For starting a D.C. motor a starter is required because it limits the starting current to a safe value.

Answer : Torque developed by a D.C. motor depends upon magnetic field, active length of the conductor, current flow through the conductors, number of conductors, radius of armature.

Answer : The armature torque of the D.C. shunt motor is proportional to armature current.

Answer : The ratio of starting torque to full-load torque is least in case of shunt motors.

Answer : A.C. series motor as compared to D.C. series motor has smaller brush width, less number of field turns, more number of armature turns, less air gap.

Answer : The speed of a D.C. series motor is inversely proportional to the armature current.

Answer : A D.C. series motor is that which has its field winding consisting of thick wire and less turns.

Answer : The direction of rotation of a D.C. series motor can be changed by interchanging field terminals.

Answer : If a D.C. series motor is operated on A.C. supply, it will spark excessively, have poor efficiency, have poor power factor.

Answer : When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.

Description : Why starter is required for starting an induction motor?

Answer : A centrifugal switch is used to disconnect starting winding when motor has picked up about 50 to 70 per cent of rated speed.

Description : List different starting methods of three phase synchronous motor. Explain any one of them.

Answer : Different Starting Methods of Three Phase Synchronous Motor: As synchronous motor is not self starting, different methods of starting are as follows: 1) By using an Induction (Pony) motor 2) ... . The rotor gets pulled into synchronism and starts running at constant speed as a synchronous motor. 

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

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

Answer : Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by means of a magnetic relay.

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

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

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

Description : A synchronous motor can be made self starting by providing?

Answer : A synchronous motor can be made self-starting by providing damper bar.

Description : How is a three phase cage induction motor self starting?

Answer : Any type of induction motor is self starting. Because the reason for torqe production require two flux displaced by some angle theta.If theta is constant with time then torqe will be constant;if ... torqe also pulsating. In induction motor this angle theta is not pulsating.so it is self starting 

Description : Is induction motor is self starting?

Answer : Single phase induction motor is not self starting. Three phase induction motor is self starting.

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

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

Answer : An induction motor has relatively high power factor at near full load.

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

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

Description : Torque developed by a three-phase, 400V, induction motor is 100 N -m. If the applied voltage is reduced to 200-V, the d'veloped torque will be

Answer : Torque developed by a three-phase, 400V, induction motor is 100 N -m. If the applied voltage is reduced to 200-V, the d'veloped torque will be 25 N -m

Description : The torque developed by any 3-phase induction motor at 0.8 p.u. slip is (A) Full-load torque (B) unstable torque (C) starting torque (D) break down

Answer : The torque developed by any 3-phase induction motor at 0.8 p.u. slip is unstable torque

Answer : Speed torque characteristic of a repulsion induction motor is similar to that of a D.C. compound motor.

Answer : In repulsion motor, maximum torque is developed when brush axis is at 45° electrical to the field axis.

Answer : A synchronous motor can develop synchronous torque at synchronous speed.

Description : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?

Answer : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-in torque.

Description : The maximum torque which a synchronous motor will develop at rest for any angular position of the rotor, at rated stator supply voltage and frequency, is known as?

Description : What is the maximum value of torque angle in synchronous motor?

Answer : The maximum value of torque angle in synchronous motor is 90 degrees electrical.

Description : What can cause high amperage on a motor?

Answer : High  amperage  can  result  in  a motor  when the  amount  of  load  increases. when  load  increases  , it  reduces  the  rotor  speed which  increases  the  slip  at  constant  synchronous  speed ... ,  as  a  result  more  current  shall  have  been  drawn  to  maintain  the  additional  load.

Description : A DC voltage source is connected across a series RLC circuit. Under steady-state conditions, the applied DC voltage drops entirely across the

Answer : A DC voltage source is connected across a series RLC circuit. Under steady-state conditions, the applied DC voltage drops entirely across the C only

← Prev Question Next Question →
editChoose topic
...