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A brushless DC motor is self-starting using only one magneto-sensitive element because the motor is of a two-phase type and is provided with a detection device which detects towards which of the two phases the rotor is mainly directed. A presetting circuit compares the detected rotor position with the state of an energizing circuit in order to set this circuit so that the energizing circuit energizes the stator phases for said specific rotor position in such a way that starting of the motor is guaranteed, although initially with an undefined direction of rotation. By presetting the commutating direction of the energizing circuit the rotor subsequently locks onto the field and rotates in the correct direction if it has started in the incorrect direction
Wiki User
∙ 11y ago
Wiki User
∙ 11y agofirst the induction motor is not a self starting because when induction motor compare to other motor the for one cycle it reaches 120 degree out of 180 degree so it is not star we need add external ressitive load so this is called self starting
Wiki User
∙ 11y agoThe continually expanding and contracting magnetic fields set up in each of the three windings, which are 120 degrees apart, combine, to form a resultant field that rotates within the stator, sweeping around the air gap. This induces voltages into the rotor bars, and the magnetic fields set up by the resulting rotor currents combine with the rotating stator field, dragging the rotor around with them.
Wiki User
∙ 11y agoBy adding an additional starting winding with a resistance in series at an angle of 90 degree from running winding we can made the motor self starter
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How can a three phase induction motor reverse direction of travel without changing input phase?
by changin the freq usin an IGBT.
How do you use a one phase motor in place of a three phase motor?
To use a single/one phase motor instead of a three phase motor is possible if you have a three phase power supply as you will only need to tap one of the three phases together with neutral and an earthwire, however to use a three phase motor instead of a single phase will require the provision of three phase power supply.
Is it necessary to have three phase rotor windings for the transmitter and motor in selsyn motor?
is it necessary to have three phase rotor
Can you reverse the wiring to make the fan reverse?
Yes if it's a dc motor with a permanent magnet field, or if it's a 3-phase ac motor. No if it's a single-phase ac motor or a dc motor with a field winding in series or parallel with the armature. <<>> Single phase AC motors can be reversed by using a reversing switch. Reverse either the start winding or the run winding connections but not both.
What is locked rotor in three phase induction motor?
A motors locked rotor current is the same as the motors starting current. This is the point where the voltage is applied to a non rotating motor, time cycle zero. Because the motor is not rotation and generating a back EMF to oppose the inrush current, the current will go as high as 6 times the running current of the motor.
Is 3 phase induction motor is self starting?
Yes, that is one of the major advantages of a three-phase induction motor.
Is a three phase induction motor self starting?
A three-phase motor has a steady rotating magnetic field generated by the stator coil, and the rotor just follows the field.
How do you start three phase induction motor?
Three Phase Induction Motor is self starting motor so you can start it by conneting to power lines directly if the power line capacity is sufficient.
Disadvantages of 3 phase induction motor?
One of the disadvantages of the 3 phase induction motor is that it requires a three wire supply. The other disadvantage is that the 3 phase induction motors have poor starting torque and high have in the rush currents.
Theory for brake test on three phase induction motor?
why three phase induction motor is delta connected
How many percent will be the starting current for motor?
Motor starting current is typically 5-7 times the rated current of the motor. (For three phase induction motors)
How do you Start three phase motors?
Three Phase Induction Motor is self starting motor so you can start it by conneting to power lines directly if the power line capacity is sufficient.
Do you need starter for 0.5HP three phase induction motor?
You never need a starter for a three-phase motor.
Is three phase induction motor used for hoisting device?
ya three phase squirrel cage induction motor used to hoist travel application in industrial cranes
How many microfarad of starting capacitor is best for 15hp 3phase motor?
Starting capacitors are only required for single-phase induction motors. They are not necessary for three-phase motors.
Is three phase induction motor continue running when any of the two phase is disconnected?
This question doesn't really make any sense - any of the two phase? A three phase induction motor requires 3 phases to start - if a single phase is lost while the motor is already running then yes the motor will continue to run. A three phase motor will not start if it is missing a phase.
Applications of induction motor?
A single phase induction motor is mainly used in fans.It is capacitor start capacitor run induction motor.In three phase induction motor squirrel cage induction motor is mainly used in elevators,lifts,cranes.slip ring induction motor is mainly used in electrically driven ships.
