Answer / ghulamsarwar3

DOL(direct online) that means full voltage starter.we are
using star delta starter to control starting torque and
current as we know motor will satart in star then after few
second it will go in delta.and now a days there is no
manual star delta starter only automatic,but functiion is
same,

Answer / bosky babu

DOL means Direct On Line Starter, can be used up to 7.5 HP Motor, and for above 7.5 HP to 150 HP a star delta starter is used.In automatic star delta starter, a timer is used to switch on the delta contactor. For higher HP ratings VFD (variable frequency drives) can be used.

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