1 Answer

Answer :

A direct online starter is used for starting motors up to 5 H.P.

Like 0 like

Related Questions

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

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

Last Answer : Three point starter can be used for both shunt and compound motor.

Last Answer : A three point starter is considered suitable for shunt as well as compound motors.

Description : What is an auto transformer starter?

Description : Online Resume Banks

Last Answer : Should you post your resume to an online resume bank such as Monster or Workopolis? What are the benefits of online resume banks? These resume banks provide thousands of employers access to ... at specific companies. Taking both approaches will heighten your chance of getting the job you want.

Description : Describe working of online UPS. List any two applications of UPS.

Last Answer : Online UPS: The block diagram of the on line UPS systems is as shown, where the load is connected to the invertor through the UPS static switch. The UPS static switch is ... 4) Healthcare: hospitals, clinics and retirement homes 5) Telecommunications 6) Special projects (events)

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

Description : Stepper motors are used in  (1) printers (2) lifts (3) amplifiers (4) oscillators

Last Answer : Stepper motors are used in printers 

Description : Which of the following motors is being extensively used in servo applications ? A. AC motor B. Field controlled dc motor C. Armature controlled dc motor D. None of these

Last Answer : Which of the following motors is being extensively used in servo applications ? A. AC motor B. Field controlled dc motor C. Armature controlled dc motor D. None of these

Last Answer : Starters are used with D.C. motors because to restrict armature current as there is no back e.m.f. while starting.

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

Description : What are the five types of single phase motors used in the industry?

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.

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

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

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

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

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

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

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

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

Last 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?

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

Last Answer : Capacitor start motor has high torque in starting

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

Last Answer : Synchronous motors are generally not self-starting because the direction of instantaneous torque reverses after half cycle.

Last Answer : As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for sound equipment.

Description : Damper winding is provided in 3 phase synchronous motors to :

Last Answer : Damper winding is provided in 3 phase synchronous motors to : provide starting torque and prevent hunting

Description : Slot harmonics are reduced in induction motors by using (A) fractional-pitch windings (B) fractional-slot windings (C) integral-slot windings (D) distributed windings

Last Answer : Slot harmonics are reduced in induction motors by using fractional-slot windings

Description : Generally, Crawling in squirrel cage induction motors is tendency to run stably at speeds as low as (A) One-third of their synchronous speed (B) One-fifth of their synchronous speed (C) One-seventh of their synchronous speed (D) One-ninth of their synchronous speed

Last Answer : Generally, Crawling in squirrel cage induction motors is tendency to run stably at speeds as low as One-seventh of their synchronous speed

Description : Which of the following test is usually conducted to determine the efficiency of traction motors ? (A) Field’s test (B) Swinburne’s test (C) Hopkinson’s test (D) Retardation test.

Last Answer : Which of the following test is usually conducted to determine the efficiency of traction motors ? (A) Field’s test (B) Swinburne’s test (C) Hopkinson’s test (D) Retardation test.

Description : In case of conductively compensated D.C. series motors, the compensating winding is provided?

Last Answer : In case of conductively compensated D.C. series motors, the compensating winding is provided in series with armature winding.

Last Answer : In case of D.C. shunt motors the speed is dependent on back e.m.f. only because flux is practically constant in D:C. shunt motors.

Last Answer : When two D.C. series motors are connected in parallel, the resultant speed is normal speed.

Last Answer : In D.C. shunt motors as load is reduced the speed will remain almost constant.

Last Answer : Differentially compound D.C. motors can find applications requiring low starting torque.

Last Answer : Most of the fractional horsepower motors have either plain or sleeve bearings.

Description : What is the difference between synchronous and asynchronous motors?

Last Answer : The motor which rotates at constant speed is called synchronous motor. And that constant speed is called as synchronous speed.  And the motor which does not rotates at constant speed are called asynchronous motor. Asynchronous motor is also called as Induction motor.

Description : 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

Description : How to Replace a Starter

Last Answer : How to Replace a Starter The starter is where it all begins. Your car is just sitting there and ready to go, but it won't. A charge is supposed to be sent to the starter and then ... the battery and tighten the connection. Start the engine to make sure that all connections have been made properly.

Description : Draw the wiring diagram of fluorescent tube. Explain the working of choke and starter. 

Last Answer : Fluorescent lamp:- Operation:- When switch is ON current flows through the choke-filament no1- starter-filament no. 2- to neutral, At that time choke induces high voltage which is applied to ... at the time of starting. ii) Starter: To make and break the circuit to start the tube. 

Description : State any four advantages of soft starter.

Last Answer : Advantages of soft starter: 1. Very low line voltage drops on motor operation 2. Reduced energy losses in the lines 3. System efficiency increases 4. Very smooth starting & operation 5. As ... may lead to lower MD billing. 13. Less mechanical maintenance. 14. Saving in operating costs.

Description : State function of starter and ELCB. (Earth Leakage Circuit Breaker)

Last Answer : i) Function of Starter:- 1. To prevent the high starting current OR to minimize the starting current. 2. To give supply failure protection 3. To give over load and short circuit protection ... an installation and cut off the circuit from power supply and avoid electrical shock to the person.

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

Description : What is the best Arduino starter kit?

Description : what is the difference between four point starter and three point starter?

Last Answer : The only difference is in the NO VOLT COIL connection in the starter, in three point starter NVC is connected to the field whereas in four point starter it is connected separately. The advantage of using ... (for above rated speed) and lead to DEENERGISE the NVC leading to turning off of the motor.

Last 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 : A relay used for protection of motors against overload is :  (A) Impedance relay (B) Electromagnetic attraction type (C) Thermal relay (D) Buchholz's relay

Last Answer : A relay used for protection of motors against overload is : Thermal relay

Last Answer : D.C. shunt motors are used for driving machine tools.

Description : Why are DC motors used in trains and not AC motors ?

Last Answer : The reason is torque. torque is inversely proportional to speed..i.e when th knowe train comes to rest position to motion.. initial speed is zero..so it requires high starting torque for ... current will flow through field and armature coils then maximum torque is available at the intial condition.

Description : State which electric motors are generally used in electro agro systems with reason.

Last Answer : 1) 3 phase induction motor is used in electro agro system for water pumping from wells as 3 phase ac supply is easily available, cost of induction motor is less, maintenance free being rugged ... as 1 phase ac supply is easily available for domestic purpose, repair is simple and easily available.

Show MoreNext Page → ← Prev Page