24. SQUIRREL-CAGE MOTORS-ADVANTAGES, DISADVANTAGES AND APPLICA-
- Cheaper in cost.
- Simple and rugged in construction.
- Maintenance cost is low.
- Explosion proof.
- Can be cooled better because of base end rings.
- More pull-out torque and greater maximum power output.
- Simple starting arrangement.
- Nearly constant speed.
- High overload capacity.
10. High power factor.
- Poor starting torque due to low rotor resistance.
- At the instant of switching on, draws a large current from the line.
- Very sensitive to change in supply voltage.
- At light load the power factor is very low.
- Speed regulation not possible.
Applications. Suitable for industrial drives of small power where speed control is not required such as:
- Flour mills
- Printing machinery
- Other shaft drives of small power.
Note. When the squirrel cage motors are used for crane or hoist work where large starting torque is more important than high efficiency owing to the intermittent nature of load, the rotor resistance is increased by employing the end rings, and sometimes the bars as well, of high resistance metal such as German silver.