Difference between DOL/Star Delta/Autotransformer


#1

DOL Starter

Used upto 5 HP

Does not decrease the starting current

it is cheap

It connects directly the motor with supply for starting as well as for running

Star Delta Starter

Used 5HP to 20 HP

Decrease the starting current by 1/3 times

It is costly

It connects the motor first in star at the time of starting in delta for running

Auto Transformer Starter

Used above 20 HP

Decrease the starting current as required

It is more costly

It connects the motor according to the taping taken out from the auto trasnformer