What Is Squirrel Cage Induction

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.

What is the meaning of squirrel cage induction motor?

A squirrel-cage rotor is the rotating part of the common squirrel-cage induction motor. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. The interaction of the magnetic fields of currents in the stator and rotor produce a torque on the rotor.

What is the difference between squirrel cage and induction?

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 are the advantages of squirrel cage induction motor?

Some advantages of squirrel cage induction motors are: Simple and rugged construction. The low initial as well as the maintenance cost. Maintains constant speed. The overload capacity is high. Simple starting arrangement. High power factor. Low rotor copper loss.

How do I know if I have a squirrel cage induction motor?

Classification of Squirrel Cage Induction Motor A normal starting torque. A normal starting current. Low slip. In this Class, pullout torque is always of 200 to 300 percent of the full-load torque and it occurs at a low slip (it is less than 20 percent).

What is the purpose of squirrel cage?

The main use of a squirrel-cage motor in a home HVAC system is that it powers the blower fan. If you have a forced-air heating system, such as a furnace, and/or an air conditioning system, the squirrel-cage motor is the part that turns the fans that blows the heated and cooled air through the ventilation system.

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.

Why is it called a squirrel cage motor?

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.

Which motor has high starting torque slip ring or squirrel cage?

Slip Ring / Wound Rotor Induction Motor: Sr. No. Squirrel Cage Induction Motor 7) Higher efficiency. 8) Low starting torque. It has 1.5 time full load torque. 9) Speed control by rotor resistance is not possible. 10) Starting current is 5 to 7 times the full load current.

Why the starting torque of squirrel cage induction motor is low?

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 is the disadvantages of squirrel cage motor?

Main disadvantage of squirrel cage induction motor is that they have poor starting torque and high starting currents. Starting torque will be in the order of 1.5 to 2 times the full load torque and starting current is as high as 5 to 9 times the full load current.

Why is the speed of the 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.

What defect is found in squirrel cage motors?

Squirrel cage induction motor cast rotor defect detection with magnetic field analysis.

What kind of cage does a squirrel need?

A pet squirrel will require a cage that is at least two feet wide, two feet deep, and several feet tall (about 0.6 meters wide, 0.6 meters deep, and at least a meter tall.) Squirrels are active animals and need to be able to move around.

What is the use of end rings in squirrel cage induction motor?

The end rings in the rotor of a squirrel cage induction motor are used to hold the bars firmly in the slots, since loose bars can get damaged quickly due to mechanical vibrations and thermal cycling. They also produce the short circuit required for the induction of current in the rotor bars.

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 does a deep bar squirrel cage work?

The resistance of the outer cage bars are more, therefore Deep Bar Double Cage Induction Motor develops high starting torque. The rotor frequency gets decreased with an acceleration of the motor towards its base speed. When the motor attains the full speed, the maximum current flows through the inner cage bars.

What is squirrel cage winding?

[′skwərl ¦kāj ‚wīnd·iŋ] (electricity) A permanently short-circuited winding, usually uninsulated, around the periphery of the rotor and joined by continuous end rings. Also known as squirrel-cage rotor.

Which type of starter is used in squirrel cage induction motor?

The Delta Start Starter is ideally suited for High Starting torque application, where squirrel cage induction motor is selected up to 50HP capacity. The Delta Star Starter also improves the power factor & reduces the demand on power supply system.

Which starter is suitable for 20 HP Delta connected squirrel cage induction motor?

The starter recommended for a 20 hp squirrel cage induction motor is: Star delta starter. Face plate starter. Direct one line starter.

Which of the following starter is applicable for squirrel cage type induction motor?

Auto-transformer starter: The Autotransformer is used in both the type of the connections, i.e., either star connected or delta connected. The autotransformer is used to limit the starting current of the induction motor. This method is used for the high rating of squirrel cage induction motors.

What is the difference between squirrel cage and wound rotor?

Difference squirrel cage rotor and wound or slip cage rotor This rotor is in the form of bars which are shorted at the end with the help of end rings. In squirrel cage rotor no slip rings or brushes. In wound or slip rotor slip rings and brushes are used. It has a simple construction.

What are the advantages of skewed slots in the rotor of a squirrel cage motor?

It is a usual practice to use the rotor of a squirrel cage motor with skewed slots i.e. slots that are not parallel to the shaft axis. This arrangement offers the following advantages : (i) It reduces motor noise and vibration. (ii) It increases the starting torque and reduces the starting current.