Answer / u.v.v.satyanarayana

dol is a direct on line starter means less than 5h.p
machines consists of roughed construction so resistance is
high.so there is no use of starting current limiting.
but in case of high rating motors starters
necessaty.

Answer / anandh

The motor will draw a high starting current until it has run up to full speed. This starting current is commonly around six times the full load current.To reduce the inrush current, larger motors will have reduced-voltage starters or variable speed drives in order to minimise voltage dips to the power supply.

DOL starters uses upto 5 HP motors.Star/Delta starters uses at above 5 HP motors.

DOL starter starts the motor in directly at on line.But Star delta starter starts the motor at directly and works at star and after 5 sec works at delta .

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