What properties make squirrel cage induction motors different from others?

Squirrel cage induction motors are characterized by their absence of brushes, which is a key feature that differentiates them from other types of motors, such as brushed DC motors or compound motors. The design of a squirrel cage motor includes a rotor made of conductors that are short-circuited at both ends, forming a "cage" structure. This design eliminates the need for brushes, which are used in other motor types to conduct electricity to the rotor.

The absence of brushes contributes to several advantages, including reduced maintenance requirements, as brushes can wear out over time and require replacement. Additionally, this design allows for smoother operation and less electrical noise. The simplified design of the squirrel cage rotor and stator also aids in reliability and durability, making these motors a popular choice for various industrial applications.

Other options, such as higher speed, lower efficiency, and complex construction, do not accurately describe the distinguishing properties of squirrel cage induction motors. While squirrel cage motors can achieve high speeds, this is not universally true compared to other motor types. Squirrel cage motors are typically efficient and have uncomplicated construction, which is part of their appeal in industrial settings.