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What are the standard voltages of 3 phase induction motor being manufactured?
The stator and rotor of a machine are not made from sold pieces of metal. They are constructed by clamping stacks of thin sheets of silicon steel, called 'laminations', together. Laminations are essential to minimise circulating currents due to voltages induced into the core/rotor when the machine is operating. These laminations are created by a stamping machine, which cuts the required shape from large sheets of thin metal.
Why rotor contactor in external resistance of slipring motor connected in delta?
rotor contactor are used to cut the resistance in slip-ring motor connected through resistance box. resistance is proportional to torque. so by controlling rotor contactor resistance can be controlled and hence torque can be controlled. for more information check torque and speed characteristic of wound motor.
Why laminations are used for iron parts of a dc machine?
Laminations minimize eddy currents, or current flow across the iron parts. This is one method to minimze stray losses.
What types of magnetic material are used for small motors?
In very small electric motors which run on dc (direct current) a permanent magnet made of iron - or of some other alloy of elements capable of being magnetised - is used to create the two poles of the stator.The rotor is built-up using windings made of insulated copper wire wound onto poles made of layers of well-insulated thin cast iron sheets which are called "laminations".The thin sheets must be well insulated from one another to minimize power wastage caused by internal eddy currents that are induced as the rotor's poles continually break the stator's magnetic field.In larger motors, which may run on either dc or ac (alternating current), the stator's magnetic field is created by field windings made of insulated copper wire wound around pole pieces which are not permanently magnetized.For use with ac the stator, like the rotor, must be constructed either:using laminations of thin cast iron sheets, well insulated from one another, to minimize power wastage caused by internal eddy currents that are induced into the stator by the field winding, orusing a non-magnetic material, such as aluminum, which cannot have eddy currents induced into it.
Why squirrel cage motor is NOT suitable for use as a DC machine?
A 'squirrel cage' rotor is used in an a.c. inductionmotor, meaning that there is no electrical supply to that rotor with the currents in the rotor , instead, being the result of induced voltages caused by currents flowing in the field windings. A rotor of a d.c. motor, is electrically connected to the supply. The two types of motor work on completely different principles, so cannot use a squirrel cage rotor.
What are the standard voltages of 3 phase induction motor being manufactured?
The stator and rotor of a machine are not made from sold pieces of metal. They are constructed by clamping stacks of thin sheets of silicon steel, called 'laminations', together. Laminations are essential to minimise circulating currents due to voltages induced into the core/rotor when the machine is operating. These laminations are created by a stamping machine, which cuts the required shape from large sheets of thin metal.
Why will the rotor of a wound-rotor motor not turn if the rotor circuit is left open with no resistance connected to it?
Because there is no current flowing in the rotor, and thus there is no magnetic field in the rotor, and thus there is no torque between the rotor and the field.
What filament is connected to the Z line thick or thin?
thin
What are slip ring motors?
slip ring motors are one in which the rotor is connected to the slip ring directly in which the slip ring also connected with the shaft so that it rotates with the rotor simultaneously..
Why transformer core cuts thin sheet?
Transformer cores are made up of insulated laminations to cut down on eddy currents induced in the core, which is an unwanted power-loss.
How do you stop brake caliper from rubbing on rotor?
The brake caliper should not touch a rotor ever. There is a metal backing plate on the brake pad that can rub the rotor if the pad wears thin enough.
Why are stator cores laminated?
Thin metal laminations are used to minimize the magnetic flux eddy current loss in the stator cores of high-speed, high-performance induction motors.
How many times can rotor be resurfaced?
You can only have them turned a few times until they are too thin to be considered safe. Usually this thickness is stamped on the rotor.
What does a armature or rotor do?
The Armature(or rotor) is a electromagnet inside a motor and alters the magnetic field inside the motor when it rotates. In DC motors it is connected to a Commutator. In AC induction motors the armature isn't connected to a power source.
What is cylindrical rotor machine?
ok actually i am looking for the answer also but this is what i have got so far,you can understand cylindrical rotor in comparison to Salient pole machines. In cylindrical rotor, as it rotates, the air gap between the rotor and stator doesnt change due to its cylindrical shape, but for salient pole machine, due to its shap, the air gap changes as it rotates, due to those dents(laminations) and since air gap is fixed for cylindrical rotor,the magnetic path reluctance is independent in respect to its position to magnetic poles
How do prepelas on a helicopter move?
The rotor and rear propeller are turned by the transmission connected to the engine
Why the rotor winding of a synchronous motor is usually connected to an external resistance during start up?
because at start the motor draws larger quantity of current and this may affected the rotor windings in order to limit current always resistance is connected.
