# Explain the necessary of starter for DC motor state various type of DC motor starter

DC motor starter.. in no

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Both d.c motors as well as three phase induction motors are self starting but these motors show the tendency to draw very high current at the time of starting. Such a current is very high and can cause demage to the motor windings. Hence there is a need of a certain device which can limit such a high stating current. Such a device which limits the high starting current is called a starter.

Two point Starter ,Three point Starter, Four point Starter

## Related Questions

What are the types of DC motor starter?
Last Answer : a. DC two point starter for series motor. b. DC three point starter for shunt motor. c. DC four point starter for compound motor.

What is the necessity of DC motor starter?
Last Answer : Eb = V - Ia ra. ∴ Ia = V - Eb / ra. At the time of starting from the rest there is no any back emf (Eb) in the armature. So a large current flows through the armature based on ... develops back emf (Eb) which regulates it's speed and armature current. This can be achieved by the help of starter.

Why starter is necessary to start the AC motor?
Last Answer : a. At the time of starting motor starting current is high (4 to 5 times). Therefore if motor is directly started the supply voltage may be disturb. b. By the help of starters starting and ... . d. Protect the motor from no-voltage and its difficulties. e. Permits automatic control when required.

Explain the necessity of starter for D.C. motor. State various types of D.C. motor starter.
Last Answer : Necessity of Starter for D.C. Motor: Armature current is given by equation Ia = (V−Eb)/Ra i) If the motor is at standstill or rest, back emf Eb is zero (as Eb= ZNP/(60A), at start speed N ... . Types of D.C. motor starters: i) Two point starter ii)Three point starter iii) Four point starter

Which type of starter is used to start the DC motor?

State the function of overload coil and No volt coil in dc motor starter.
Last Answer : Function of Overload Coil: When DC motor is overloaded, the overload coil carries the overload current and produces strong magnetic field to attract a plunger, which short the terminals of ... dc motor is prevented from restarting automatically on recovery of supply without starter and protected.

An across-the-line starter is typically used for which of the following applications? A. Reduced-current starting of large motors B. Low torque starting of small motors C. Low resistance starting of DC motors D. Full-voltage starting of motors

In a faceplate-type motor starter, the starting arm is held in the 'OFF' position by a/an _____________. A. cotter pin B. magnet C. electrical circuit D. strong spring

The rotor slots of a repulsion-type motor are generally skewed (placed nonparallel to the rotor axis) to _________. A. produce a constant starting torque B. permit a greater air gap with the starter C. permit a smaller air gap with the starter D. reduce eddy current losses

To check the three line fuses of a three-phase system consisting of a three-phase motor, you must _____________. A. place the starter in the 'stop' position B. make sure the motor is operating at full ... leads across the 'hot' ends of the fuses D. place the leads across the bottom ends of the fuses

Motor starter or controller contacts may become welded together if the contacts _____________. A. open too quickly and arc B. close under excessive pressure C. open or close too quickly D. close under excessive starting current

Which of the following actions must be carried out before a voltage tester can be used to test the three line fuses to a three-phase motor? A. The fuses must be removed from the circuit. B. The ... disconnected and tagged. D. Nothing need be done as long as the motor is running under a light load.

Motor controller or starter contacts may become pitted and welded together if the contacts _____________. A. open under loaded conditions B. close slowly with light pressure C. open too quickly and arc D. close quickly with proportionate pressure

Excessive heat in an operating motor controller can result from _____________. A. a closed starter contact B. loose connections C. missing arc chutes D. low motor starting torque

If the contacts of a motor starter or controller fail to drop out when the 'stop' button is depressed the ____________. A. contacts are carrying excessive current B. contacts have become welded together C. shading coil is broken D. shading coil is loose

Low voltage releases as used in some shipboard motor starter and control equipment will have which of the following characteristics? A. They trip circuit contactors when the motor starts to overspeed. B. ... coil of the starter. D. They allow the motor to restart upon restoration of normal voltage.

The diagram shown in the illustration represents a _________. EL-0058 A. dual speed, 2-winding motor controller B. navigation running light circuit C. single phase, 2-motor selectable starter D. common fluorescent lighting circuit

What is the Necessity of Starter of an Induction Motor?
Last Answer : Induction motors, when direct-switched, take five to seven times their full-load current and develop only 1.5 to 2.5 times their full-load torque. This initial excessive current is ... electrical equipment connected to the same lines. Hence, a starter is necessary to overcome this objection.

What are the advantages of star-delta starter with induction motor?
Last Answer : The main advantage of using the star delta starter is reduction of current during the starting of the motor. Starting current is reduced to 3-4 times of current of Direct online starting Hence the starting current is reduced , the voltage drops during the starting of motor in systems are reduced

Why star delta starter is preferred with induction motor?
Last Answer : Star delta starter is preferred with induction motor due to following reasons: Starting current is reduced 3-4 times of the direct current due to which voltage drops and hence it causes less ... caused. In addition, starting torque is increased and it prevents the damage of motor winding.

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.

Which of the following precautions should be taken when troubleshooting various power circuits using a common solenoid-type mechanical voltage tester (wiggins)? A. Never use this tester on circuits greater ... voltage expected in the circuit in order to prevent damage from an off-scale reading.

Draw and explain star delta starter for 3 phase induction motor
Last Answer : Star Delta Starter for 3 Phase Induction Motor:  Diagram Explanation: The stator winding of the motor which is designed for delta operation is connected in star during starting ... which connects stator windings in delta connection. Now each stator phase gets full line voltage VL.

Explain DOL starter used for 3 phase induction motor.
Last Answer : DOL Starter Used for 3 Phase Induction Motor: The direct online starter consist of overload relay (OLC), contactor, start-push button S1 (normally open), stop-push button S2 (normally ... The overload coil (OLC) protects the motor against overload and short circuit by opening the contact D.

Draw power and control circuit for definite time-limit starter for slip-ring induction motor. Explain its working.
Last Answer : Definite Time-limit Starter for Slip-ring Induction Motor: This starter is used for automatic control of acceleration of slip-ring induction motor at the time of starting. In this starter, the ... each phase, shorting the rotor winding terminals and final acceleration of the motor takes place.

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):

For a DC motor, what major component in addition to the field winding and the armature winding is necessary? w) a commutator x) a stator y) a battery z) a rotor

Draw the power and control circuit diagram for forward — stop — Reverse type DOL starter for 3 phase induction motor.
Last Answer : Draw the power and control circuit diagram for forward — stop — Reverse type DOL starter for 3 phase induction motor.

If overloading a DC machine becomes necessary in an emergency, you should ____________. A. cool the machine with portable blowers and fans B. hold thermal overload relays open with blocks of ... the windings for cooling D. increase the residual magnetism value of windings to reduce eddy currents

The electrical energy necessary to power a sound-powered telephone's small vibrating bell is obtained from _________. A. the emergency batteries for the general alarm B. each station's hand-cranked generator C. the emergency switchboard D. normal 115 volt DC supplies

Where is the starter motor on a xsara Picasso 1.6 petrol?

How do you start a motor without a starter?
Last Answer : By the use of auto transformer and bridge rectifier we can startdc motor.

Develop the control circuit for star-delta starter used for starting a 3 ∅ induction motor.
Last Answer : Control Circuit for Star-Delta Starter: 1) Automatic Star-Delta Starter: OR 2) Semi- automatic Star-Delta Starter:

Develop power and control diagram for secondary frequency acceleration starter of slip ring induction motor.
Last Answer : Power and Control Circuit diagram for secondary frequency acceleration starter of slip ring induction motor:

Describe the power and control circuit for automatic Star-Delta starter for 3-phase induction motor.
Last Answer : Power circuit: Control circuit:

A 3-phase delta connected squirrel cage induction motor when started with a DOL starter has a starting torque of 600 NM. Its starting torque when star delta starter is used:
Last Answer : A 3-phase delta connected squirrel cage induction motor when started with a DOL starter has a starting torque of 600 NM. Its starting torque when star delta starter is used: 200 NM

Consider the following statements: Star delta starter is used in 3-phase induction motor because it  1. Prevents heating of the motor winding  2. Ensures permissible minimum starting current  3. Is regulated by electricity ... and 4 are correct (c) 1, 3 and 4 are correct (d) 1 and 2 are correct
Last Answer : Consider the following statements: Star delta starter is used in 3-phase induction motor because it  1. Prevents heating of the motor winding  2. Ensures permissible minimum starting current  3. Is regulated by ... and 4 are correct (c) 1, 3 and 4 are correct (d) 1 and 2 are correct

The coils of D.C. motor starter are wound with wire of?
Last Answer : The coils of D.C. motor starter are wound with wire of manganin.

Last Answer : In a manual shunt motor starter over load relay is connected in series and no volt relay in parallel with the load.

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

Why starter is required for starting an induction motor?

The electrical schematic shown in the illustration represents a/an ____________. EL-0017 A. across-the-line starter B. primary-resistor starter C. autotransformer starter D. part-winding starter

When a fluorescent lamp fails to light, the trouble can be in the _____________. A. lamp B. starter C. ballast D. all of the above

When a fluorescent lamp has reached the end of its useful life, it should be replaced immediately, or the resultant flashing may _____________. A. blow the lamp's circuit breaker B. explode, ... fly in all directions C. short circuit the ballast transformer D. damage the starter and the ballast

An across-the-line starter provides ___________________. A. maximum torque B. slow starting power C. high speed D. reduced voltage

Which of the following components are used to assemble a fluorescent lighting system? A. Lamp B. Starter C. Ballast D. All of the above

Which component of the circuit shown in the illustration is the starter? EL-0081 A. A B. B C. C D. D

Difference Between A Four Point Starter And Three Point Starter?
Last Answer : The shunt connection in four point stater is provided separately form the line where as in three point stater it is connected with line which is the drawback in three point stater.

What is the necessity of starter?
Last Answer : Its function is to reduce starting current and also provide protection against over load and over voltage.