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Squirrel cage motors are a subclass of induction motors, which harness electromagnetism to generate motion. They are so-called “squirrel cage” motors because the shape of their rotor – the inner component connected to the output shaft – looks like a cage.
What is the difference between induction motor and squirrel cage motor?
Key Differences Between Slip Ring & Squirrel Cage Induction Motor. The motor whose rotor is wound type such type of motor is called slip ring induction motor, whereas the squirrel cage motor, has a squirrel cage type rotor. The starting torque of the slip-ring motor is high, whereas in squirrel cage motor it is low.
What is meant by squirrel cage?
1 : a cage for a small animal (such as a squirrel) that contains a rotatable cylinder for exercising. 2 : something resembling the working of a squirrel cage in repetitiveness or endlessness.
Where would you use a squirrel cage motor?
Squirrel cage induction motors are commonly used in many industrial applications. They are particularly suited for applications where the motor must maintain a constant speed, be self-starting, or there is a desire for low maintenance. These motors are commonly used in: Centrifugal pumps.
Why is the speed of a squirrel cage motor fixed?
‘Fixed’ speed induction generators Because the speed variation from no load to full load is very small, the term ‘fixed’ speed tends to be widely used. The design and construction of the stator and rotor of an induction generator are similar to that of a large induction motor having a squirrel-cage rotor.
Why are squirrel cage motors so reliable?
The interaction of the magnetic fields produced by the stator and rotor windings produces a torque on the squirrel cage rotor. Squirrel cage induction motors are used a lot in industry – as they are reliable, self-starting, and easy to adjust.
Is a squirrel cage motor AC or DC?
Squirrel cage motors are a subclass of induction motors, which harness electromagnetism to generate motion. The AC current passed through the stator creates an EMF that fluctuates with the AC frequency, which “rotates” around the rotor, inducing opposing magnetic fields in the rotor bars, thus causing motion.
Why is Alyohin compared to a squirrel in a cage?
Alyohin, the narrator in the story, ‘About Love’ is compared with the caged squirrel. The Luganovichs and Ivan and Burkin develop an analogy of squirrel in the cage. The phrase Alyohin is said to rush around like a squirrel in the cage’ is repeated in the story too. Instead, he is entangled in love and poverty.
What is the best cage for a squirrel?
Cages at least 3 feet wide and 4 feet deep are ideal for housing two to three adult flying-squirrels as they provide sufficient room for gliding and movement without limitation. That said, the bigger the cage, the better it can accommodate more squirrels.
How do you make a squirrel house?
A squirrel house should be made of 1-inch lumber, not sanded smooth. The entrance hole should be 3 inches in diameter and facing south. The house should be placed 20 to 30 feet above ground on a tree at least 10 inches in diameter and close to a branch, so the squirrels can easily dart inside.
What type of starter Cannot be used for squirrel cage motors?
So we cannot use is this method for starting. Important Points: The star-delta starter method of starting three-phase induction motors is very common and widely used among all the methods.
Can a squirrel cage motor be used as a generator?
Three phase squirrel cage induction motors can also be used as generators. For the motor to work as a generator instead of a motor the rotor must be spun faster than its stator’s synchronous speed. This will cause the motor to generate power after building up its residual magnetism.
Why do squirrel cage motors have low starting torque?
It suffers from the disadvantage of a low starting torque. It is because the rotor bars are permanently short-circuited and it is not possible to add any external resistance to the rotor circuit to have a large starting torque.
What defect is found in squirrel cage motor?
Squirrel cage induction motor cast rotor defect detection with magnetic field analysis.
How do you control the speed of a squirrel cage motor?
out of the several methods of speed control of an induction such as pole changing, frequency variation, variable rotor resistance, variable stator voltage, constant V/F control, slip recovery method etc., constant V/F speed control method is most widely used.
Is standard for squirrel cage induction motor?
1.1 This standard covers the requirements and performance of energy efficient, 3 phase squirrel cage induction motors in 2, 4, 6 poles for frame sizes from 71 up to and including 315L having output ratings as specified in IS 1231 : 1974 ‘Dimensions of three- phase foot-mounted induction motors’ for continuous duty (S1).
What are the advantages of a wound rotor motor over a squirrel cage motor?
Another important advantage over squirrel-cage motors is higher starting torque. The speed and torque characteristics of a wound-rotor motor can be adjusted by changing the external resistance, unlike a squirrel cage motor which has a fixed characteristic. This is useful for speed control of the motor.
What 3 things are needed for an induction motor to work?
A 3-phase induction motor includes two essential components namely the stator & the rotor. In this motor, the stationary part is the stator whereas the rotating part is the rotor. In this motor, the load is connected to the shaft. Three-phase armature winding can be wound over the stator.
Which motors has high starting torque?
Series wound DC motors are best for applications that require high startup torque, without the need for speed regulation. Like a shunt motor, as a load is applied to a DC series motor, the motor speed decreases, which reduces the back EMF and increases the net voltage.
Why synchronous motors are not self-starting?
Above a certain size, synchronous motors are not self-starting motors. This property is due to the inertia of the rotor; it cannot instantly follow the rotation of the magnetic field of the stator. Once the rotor nears the synchronous speed, the field winding is excited, and the motor pulls into synchronization.
What is the difference between a squirrel cage motor and a wound rotor motor?
Rotor itself automatically adjusts to the number of poles as that of stator. Squirrel cage motor consists of cylindrical rotor having skewed slots in which aluminum bars are placed. No windings are present in squirrel cage rotor.
How is the direction of rotation of a squirrel cage motor reversed?
The direction of rotation of these motors can be easily changed. This is accomplished by reversing the connections of two of the power lines to the motor leads. The result is the rotating magnetic field will reverse, and the rotor will turn in that direction.
