DOL starting of induction motors is generally restricted for

A. Variable speed motors
B. High horsepower motors
C. High-speed motors
D. Low horsepower motors

Answer with Explanation:
D. Low horsepower motors

Explanation:
Direct On Line Starter method is a common method of starting of Cage Induction Motor. The motor is connected through a starter across the full supply voltage. 
 
Direct Online Starters (DOL) applies full line voltage to the motor terminals, the starters or cubicle locations. This is the simplest type of motor starter.

A direct on line starter can be used if the high inrush current of the motor does not cause an excessive voltage drop in the supply circuit.

Direct online starters are commonly used to start small water pumps, conveyor belts, fans, and compressors and Low Horse Power Motors 

In the case of an asynchronous motor (such as the 3-phase squirrel-cage motor), the motor will draw a high starting current until it has run up to full speed.




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